Thought Experiment: Where Is It Worth Saving Weight on a Trail Bike?

Jul 22, 2021
by Henry Quinney  
2021 Field Test Tom Richards photo
Trail biking is a broad catagory and means different things to different people.

Trail bikes can be a strange proposition. The days of the sub-30lb goal seem to be shrinking into the distance in our mirrors as we move away from the notion that weight is one of the main parameters of performance.

The problem, if it even is a problem, is that the modern trail bike is simply so capable. Adding slightly heavier components to keep up with the bike's capabilities can be a slippery slope. First, it might be a burlier fork, then heavier tires, and maybe an insert. Before you know it, your trail bike is more of the broadsword than the rapier you imagined.

But where, if anywhere, is the place to save weight? What components yield the greatest ratio of performance per gram? For this article, I’ll be working within a certain brand's range to try and keep things consistent. Also, I’ll also often be going for top of the line equipment if only because it removes a variable when it comes to trimming excess weight. Also, for argument's sake, I’ll consider the total weight of the bike to be a respectable 14.5 kg (32 lb). I know it is something of a contradiction to have a set weight for a bike when we're talking about the changing components to alter the weight.

My last caveat is that this bike will be a trail bike that might be shorter on travel than its enduro counterparts but it’s still meant to be ridden aggressively on technical trails.



Forks

RockShox 2020
The Pike brings the same damper technologies as the bigger forks to a trail bike package.

In my experience, the trouble with aggressive trails bikes is that they often soon outstrip their fork, especially for heavier riders or those who have choppy terrain on their doorstep.

Of course, the slacker the head angle the more it requires in terms of stiffness. I've found that it tends not to be torsional stiffness that gets affected, so much as fore and aft stiffness and the front wheel wants to come underneath the headtube under heavy braking.

So, how much weight is added going from a RockShox Pike Ultimate to a Lyrik Ultimate?

Based on a 29” model, the weight penalty in itself is 238g. Going to a Zeb, should you really want to, would be a 398g increase. The travel can be adjusted internally, although it should be noted the Zeb would be at 150mm, where the Pike tops out at 140mm in the 29er.

Going from a Pike to a Lyrik is a 13% weight increase. It represents a 1.6% increase compared to the total weight of the bike.

Going from a Pike to a Zeb is a 22.7% increase. It represents a 2.7% increase compared to the total weight of the bike.

Is bigger always better? Or even needed?

What about Fox’s range? This time, let’s look at the claimed weight of their range going from the 34 to 38, again in 29”.

Starting with a weight of 1820g for the non-StepCast 34, going to a 36, would be a 330g increase. Should that not be aggressive enough it would be an additional 190g to go to the all-out 38 enduro fork. Again, you may well have issues with too much additional travel. The 34 has a maximum of 140mm, whereas the 36 has a minimum travel of 150mm and the 38 160mm.

Going from a 34 to a 36 is a 18.1% weight increase. It represents a 2.3% increase compared to the total weight of the bike.

Going from a 34 to a 38 is a 28.5% increase. It represents a 3.6% increase compared to the total weight of the bike.



Shocks

Fox Float X and DHX 2022
The Float X offers a halfway house between the inline DPS and the twin tubed X2.

Working with a 210x55mm shock, a Fox DPS, which is a particularly light monotube shock, weighs 278g. To add a piggyback with their Float X model would add 175g. If you wanted to go to a Fox DHX coil from the DPS, including an 450lb SLS spring, you would be looking at adding 485g.

Going from a Fox DPS to a Fox Float X is a 62.9% increase but that represents a 1.2% weight increase compared to the total weight of the bike.

Going from a Fox DPS to a Fox DHX Coil is a 174.5% increase. It represents a 3.3% weight increase compared to the total weight of the bike.

RockShox 2020
Three flavours of Deluxe to choose from.

And with RockShox, how do their weights stack up, especially within the trail-friendly Deluxe line? Working with a 210x50mm shock, a Deluxe Ultimate weight 340g. To add a piggy-back would add 113g. If you wanted to go to a coil shock, including 400g for a spring, you would be looking at 806g.

Going from a Deluxe Ultimate to a Super Deluxe Ultimate is a 33% increase but that represents only a 0.8% weight increase compared to the total weight of the bike.

Going from a Deluxe Ultimate to a Rockshox Super Deluxe Coil Ultimate is a 137% increase. It represents a 3.2% weight increase compared to the total weight of the bike.



Wheels

It's much more than just different materials that effect a wheel's weight.

Using Hunt’s alloy wheel range and starting with their XC Wide 1647g wheels could be an option for trail riders trying to shed some weight. To go to their Trail Wide wheels would see a weight increase of 184g. To go all the way to the Enduro Wide wheelset from the XC Wide would be a difference of 503g.

Going from the XC Wide to the Trail Wide is a 11.2% weight increase. It represents a 1.27% increase compared to the total weight of the bike.

Going from the XC Wide to the Enduro Wide is a 27.8% increase. It represents a 3.4% increase compared to the total weight of the bike.



Tires

Garda Bike Fest 2018. Lago di Garda Italy. Photo by Matt Wragg
Tire companies make different casings and compounds to suit your needs.

For the sake of simplicity, we’ll talk about tires as a pair. A pair of 2.4” Nobby Nics in the Super Ground casing weighs 1780g. To go for something more aggressive like the 2.35” Hans Dampf in Super Trail would see a weight increase of 370g. If you wanted to prioritise grip even further then a set of 2.4” Magic Marys, also in Super Trail, would see a weight increase of 660g over the Nobby Nics.

Going from the Nobby Nics to the Hans Dampf is a 20.8% weight increase. It represents a 2.6% increase compared to the total weight of the bike.

Going from the Nobby Nics to the Magic Marys is a 37.1% increase. It represents a 4.6% increase compared to the total weight of the bike.



Brakes

Four piston calipers are becoming more and more common on trail and XC bikes.

Some Shimano XT brakes, again as a pair but not including rotors come in two versions with two or four pistons. A set of two piston BR-M8100 weighs 571 grams.

The BR-M8120 four piston brakes weigh an additional 104g or 18.2%. It represents a 0.7% increase compared to the total weight of the bike.

With brakes, there is another large variable to change - rotor size. So, assuming we kept the weight the same but changed the rotor size what difference would there be?

Assuming the trail bike has 180mm as standard then a set of 180mm rotors is not only the smallest you can run but also means there is no need for adaptors. A set of Shimano XT RT86 six bolt rotors would weigh a combined 290g. A 200/180mm set up would weigh 63g more. A 200/200mm setup would weigh 126g more than the 180mm rotors.

Going from the 180/180mm setup to the 200/180mm setup is a 21.7% weight increase. It represents a mere 0.4% increase compared to the total weight of the bike.

Going from the 180/180mm setup to the 200/200mm setup is a 43.4% weight increase. It represents a mere 0.9% increase compared to the total weight of the bike.



Drivetrain

Shimano Deore XT 8100
How much weight, compared to the total weight of our bikes, does a more expensive drivetrain really save you?

Drivetrains are a little bit different in that they’re not so specific to a bike's intentions. If you do care though, how much weight can you save with a different drivetrain?

Of course, with drivetrains weight is far from the only indication of performance. Unlike the other products compared, where they all hold a similar place in the brand's product hierachy and cost similar amounts. But if you were interested, what would the difference be if we compare weight increase to cost reduction? For reference, a Deore groupset retails for $296, SLX for $410, XT for $612 and XTR for $1,375.

XTR to XT represents a 15.9% change which is equal to a 247g increase. This would be a 1.7% increase to the total weight of our bike. It is a 55.5% reduction in cost.

XTR to SLX represents a 20.7% change which is equal to a 322g increase. This would be a 2.2% increase to the total weight of our bike. It is a 70.1% reduction in cost.

XTR to Deore represents a 35.4% change which is equal to a 551g increase. This would be a 3.8% increase to the total weight of our bike. It is a 78.5% reduction in cost.

SRAM GX AXS review
SRAM GX AXS review
You're not always paying for less weight, sometimes you're paying for outright performance.

What about SRAM - what are the price and weight differences between mechanical and electronic gearing? Let’s look in particular at the recently released SRAM GX AXS and its mechanical counterpart.

The GX AXS derailleur and shifter weigh a total 522g and have an RRP of $600. The mechanical GX shifter and derailleur weighs 462 grams, including cable and housing and cost $170.

Upgrading from GX to GX AXS represents a 13% change which is equal to a 60g increase. This would be a 0.4 increase to the total weight of our bike. It is a 253.9% increase in cost.



Frame

Nukeproof Giga
Instead of enduro-fying your current trail bike, would you be better of with a burlier platform?

So, what if you’ve gone for the burliest, and heaviest option for each part so far. If you were to change the frame itself what kind of weight differences are there typically? In this instance, let's look at a 29" Nukeproof Reactor in a size Medium.

A Mega weighs 220g more, which is an increase of 1.5% increase to the total weight of our bike.

A Giga weighs 280g more than a Reactor, which is an increase of 1.9% increase to the total weight of our bike.

So, essentially, going from a trail bike frame to a all-out super-enduro frame represents half of the change, in the context of the total weight of our bikes, from going between XTR and Deore.



Where and why?

If it were my 14.5 kilogram trail bike, where do I think is the most efficient place, performance per gram, to make a bike more capable? It's a bit of a cop-out, but it really depends on where you're riding. Somewhere steep, my answer is brakes, somewhere rough, that changes to suspension...

If we set ourselves to goal of an aggregate 5% total weight gain then I would opt for:

Stopping Power (0.4% - 63g) - I think adding larger rotors improves the most performance for the smallest trade-off. 200/180mm rotors are a great compromise of power and heat management, even on two pots. They'll also combine with my next choice to yield greater performance yet. There's no point in have large amounts of braking power if you don't have any grip. I know four-piston brakes benefit those on long and arduous descents, but hopefully my large rotors will do a lot of the heavy lifting in that regard.

Goldilocks tires (2.6% - 370g) - Without a doubt, tires are one of the areas that can dictate a whole bike's performance. They're the bike's sole contact patch unless you opt to use your face, and all the burliest componentry in the world won't save you have no grip. However, they're also heavy and the weight can quickly add up. For general trail riding a middle-of-the-road tire, in this instance, a Super Trail Hans Dampf, offers a good blend of security, platform and tread depth. Trail bikes can end up chasing their own tail with heavy wheels and tires and lose the sharpness that makes them such a pleasure to ride in the first place.

A Stiffer Fork, in this case a Lyrik (1.6% - 238g) - With heavier braking and more grip, it might not be too long before you want a stiffer fork. I think that a burlier fork goes a long way to helping a bike feel consistent and planted on rough fast trails, especially when applying the front brake. However, I don't think any of the new larger-stanchioned enduro forks are ever really needed on a trail bike. Something such as a Lyrik or 36 is ample, especially with the Charger and Grip2 dampers being as good as they are. At just 1.2% a piggyback shock would be the next on the list but sadly it would take me outside my 5% weight change.

James Jeannet and Dominick Menard through the trees and ferns deep in Mont Saint Anne QC.
Ripping through a singletrack trail on an efficient bike, whilst maybe not as extreme as enduro or downhill, can be one of the most rewarding types of riding.

What didn't I chose?

I haven't gone for the most extreme option in any case. I know there is an argument to say that "travel weighs nothing", and although it's not something I disagree with, often the choices made to enable larger amounts of travel do add up in terms of weight. Although interestingly enough, not always on the frame.

This problem can be approached two ways - if you're somebody that runs downhill tires, inserts, a 38 and the biggest brakes you can find, then I see little point in opting for a shorter travel frame. By that point you've already chosen all the heavy bits, you may as well lean into it.

In for a penny in for a pound, I say.

However, if you're never going to open the floodgates and run that sort of equipment then a trail bike with heavier parts as needed can make a wonderfully versatile bike.

When running heavier wheels it often isn't a noticeable performance change that you're chasing, and the benefit is normally increased resistance to damage. However, adding rotational mass can really compromise a bike's feel and turn a bike from a pleasure to a chore. For me, on a trail bike, I'd rather just take a measured approach when riding particularly rough trails and enjoy all the benefits that they can yield.



Special thanks to Competitive Cyclist for helping me fill in the gaps for the one or two product weights that we didn't have on PB record.



So, if we're trying to keep our weight as low as possible, where to spend and where to save? What has the bigger impact on performance? A large change like aggressive tires? Or a combination of changes like a piggyback shock, big calipers on larger rotors and a burlier set of wheels?

With 5%, or around 750g, what would you add to beef up this trail bike?

At what point are we selling ourselves short and start to think about looking at a more aggressive frame? Or are we looking for short-travel-pop rather than the brutish charms of a longer travel bike?



244 Comments

  • 196 9
 Probably lose the spare tire most people carry around their midsection. Then dont even worry about being a weight weenie
  • 104 1
 What about the weight of the weenie tho?
  • 5 1
 Serious stupid question. Is all weight not in wheels equal? Or is it about feel? So a light bike feels great to anyone but in terms of speed it’s total weight?
  • 8 3
 @johnny2shoes: Rotational components have the biggest impact. Moving components would have a bigger impact than non-moving components. E.g. unsprung weight in the frame/cockpit is less important than sprung weight in the fork lowers/rear triangle/cassette/derailleur. Most non-pros can't detect those difference, though.
  • 7 2
 @johnny2shoes: Weight savings or gains is about pure feel unless you race uphill and are counting watts per KG. Lighter bike takes less energy to ride up a hill. But most of us can get to 3 watts/kg (FTP over rider weight) having different body shapes, different weight bikes, and be in great physical shape... Tire tread and rolling resistance is whole other conversation, but can definitely make your bike accelerate quicker or slower. The short answer to your question:

No it's not equal and yes it's about feel.
  • 37 2
 As the saying goes - don't buy upgrades, ride up grades
  • 4 3
 @johnny2shoes: To some degree, reducing weight up high, like saddle, bars, stem, levers, will make a bike feel more flickable. Unless you're going from a really heavy cockpit/saddle combo to a really light combo all at once, you'd be hard pressed to notice. The advantage will still be there, in terms of quicker handling, and better responsiveness, but you'll get used to it within a ride and only notice it if you jump on a much heavier bike.
  • 10 0
 Who doesn't go down the weight weenie path in reagrds to tires every couple of years. I run cushcore and recently decided to try going back to an EXO casing on the rear (normally DD/DH/Grid Gravity casing). The bike felt great for the first 30 minutes until I ripped a huge gash in it. Back to cushcore and 1200g tires on the rear where I never have to worry about my lack of finesse, poor line choice, or bad luck.
  • 11 1
 Agreed, but two pounds off a bike is....two pounds off a bike regardless if the rider is 225lbs or 185lbs
  • 10 0
 Some of us can't lose anything off our midsection though without looking anorexic. At 140lbs (63kg) I want a lighter bike because it's easier to maneuver. I generally agree with everything this article said having recently gotten a light trail bike and experimenting with different parts. Some things, especially going too heavy on tires, kill the feel of it. I'm using EXO+ casings for the 120tpi and they feel like the best balance of weight and rolling resistance. Came with a 36 at 140mm, dual piston XT's, and a DPX2 rear shock. Next thing I'm swapping is the XT cassette when I wear it out for an XTR which will save another 103g approximately. Currently at 29.4 lbs. (13.3kg) and can maybe shed another half pound or so without going overboard.
  • 3 0
 True, but my bike weighs about a quarter of my weight, so I wouldn't mind having it a bit lighter.
  • 10 0
 @iliveonnitro: I believe your examples of sprung/unsprung weight are backwards.
  • 1 0
 ..
  • 8 0
 I think one thing we must consider that this article does not mention is that riders of different weights may affect where you choose to save weight too... to a lighter rider, losing a kg off the bike makes a bigger difference than it does to a heavier rider in terms of rider to bike weight ratio. Heavier riders may also be harder on their wheels and feel flex in frames or forks more easily. Thus I think the rider weight to bike weight ratio should be a thing...
  • 3 0
 @GBeard: I may be informing you of something you already know here but just FYI, 60tpi tires are more puncture resistant than 120tpi, the higher thread count allows the tire to conform to the trail better, not make it more puncture resistant...
  • 2 0
 @mattddrchs: Are you an anarchist?Seriously, what would happen to the global economy if we followed this advice?

Imagine everyone working on being better instead of buying better... I cant even - Im gonna need to call in sick today.
  • 4 23
flag dkos (Jul 23, 2021 at 8:18) (Below Threshold)
 fuck off, no one here needs your fatphobic garbage. bikes are for everyone, asshole
  • 2 26
flag dkos (Jul 23, 2021 at 8:20) (Below Threshold)
 @GBeard: "without looking anorexic"

oh gee golly, I would HATE to look like I have a literal and uncontrollable illness, that tons of normal and good people struggle with daily!!!

how do you people have so much f*cking hate in you??
  • 10 0
 @dkos: grow up, stop acting like a whiney 15 year-old brat. @GBeard was commenting on his thin size and lack of room to lose much if any weight himself. Do you go thru your whole life looking for things to be offended by? Looks like the majority of your comments are nothing but miserable troll affairs.
  • 7 0
 @dkos: "how do you people have so much f*cking hate in you??"

Ask yourself the same question.
  • 4 0
 @Eatsdirt: I think you're right. Correct principles, swapped words. Thanks!
  • 1 0
 ...
  • 1 0
 @SonofBovril: You nailed it.
  • 1 0
 @GBeard: sounds like an Optic!
  • 1 0
 Trail 429
  • 1 0
 @topherdagopher: I did the same thing last week with a Minion semi exo. Now I have to fix the damn thing and re set up the tubeless. Great while it lasted but need a heavier casing.
  • 1 0
 What @HenryQuinney fails to mention is that a 32lb bike for a 65kg rider is the same bike to rider ratio as a 47lb bike for a 95kg rider.
  • 60 1
 Not even sure what constitutes a "trail bike" anymore, but if I had to have one bike to do it all, I wouldn't worry about saving weight. I would however have two wheelsets. One for bigger outings and/or smoother trails with lighter casing/faster rolling tires sans inserts and one for real descending with heavier casing, slower rolling tires.

Outside of wheel weight, its really not worth trying to cut weight anywhere on a trail bike in that you really won't feel it or you'll end up with something that is uber expensive for very little gain. After all, you aren't racing your trail bike uphill, right?
  • 19 0
 Park set vs. trail set. Works great.
  • 3 0
 This ^^^^
  • 33 0
 I can't honestly tell if my 2(!) bottles are full or empty by how the bike rides, but I can feel the difference between a DD and EXO rear tire immediately.

Which is why I bought a 27lb Downcountry bike 9 months ago that now weighs over 31lbs.
  • 2 0
 I have to agree! I have an Izzo Blaze as my trail bike. Came with DHRs and DT Swiss M1900 wheels. Heavy but lots of grip. I’ve since upgraded to Raceface Next R 31 wheels but also went for a Dissector up front and a Rekon in the back. While I love the weight savings, I get sketched out on loose stuff or wet stuff and don’t have as much fun. If I hadn’t already sold the DTs, I’d have kept them with the DHRs left on and rotate the wheels for whichever trails I was hitting. Only other expense is a second pair of rotors. Sure beats changing tires if the budget allows for it!
  • 2 0
 This is the best approach.

Tires make the biggest difference in performance, but they also make the bigger difference in drag and rotation weight. It would only be logical in that case to tailor the tires for the expected conditions and ride type.

However, there also seems to be a shift even within WC XC to run some sort of insert. I might be inclined to run both wheelsets with inserts, but also run a lighter insert in the "trail wheels". So you're not giving up support and/or puncture resistance while being able to run a slightly lower pressure, but getting a faster rolling tire as well.
  • 4 0
 This is what I do - I have a set of light carbon wheels with light tires (Recon Race/Ikon) for day to day trail riding, and a burly set of wheels with DH tires for uplift days (MM/NN).
  • 4 0
 I use my trance sx for everything, but would like to run it with 2 wheel setups. 1 with lightweight rims and tires for in town valley trails, and one set for the mountain. That way I'm not running my minions down on xc trails.
  • 5 0
 @alxtomlinson: this makes total sense and is something I've considered doing but I just end up staying with the burly setup.
  • 1 0
 @watchtower: I stay with the burly set up all around. It'll be the little tech line that I would mess up as soon as I get light wheels. You know that spot or two on your basic ride that are on par with a bike park section. Murphys law! I'll dent the shit out of a lighter rim on the one rock I needed to avoid. I'm a big dude though, rims are a soft spot for me, figuratively and literally.
  • 2 0
 I want to do this and I do have two wheelsets but I get so lazy about also having to swap brake rotors and cassettes.
People who do this regularly, do you guys own two sets of rotors and cassettes?
  • 3 0
 @rideallday110: yes. It makes the swap even easier
  • 2 0
 @rideallday110: cassettes are consumable and eventually need to be replaced so I suppose having a second cassette is like having one ready for when the current one is spent. Brake rotors are thankfully one of the affordable bike parts.

This is very interesting - I'm going to get a second wheel set and try this out! Beats the expensive endeavor of trying to go all weight weenie on frame and components
  • 1 0
 My home trails (literally, on my farm) that I ride everyday on my shorter travel bike, I run different tyres to trails that I’m not so familiar with. For home I use lighter casings with lower rolling resistance. It’s currently an ardent on the front and an ikon on the back. When I’m going to somewhere else that I am less familiar with, I run more aggressive tyres like DHR up front with an aggressor or SS on rear. I don’t have a spare wheel set but also don’t often take the trail bike on the road with me. Last time was in May. And the time before that was last October.
  • 1 0
 I've come to the conclusion that it's all about compromise. You have to turn it down if you are riding light fast wheels.
  • 39 3
 One has to wonder why two piston brakes are still being spec'd on a lot of bikes... Aside from Road / Gravel and WC XC racers. As shown here the weight increase to 4 piston brakes is very small, especially relative to the stopping power gained with 4 piston brakes (even on 160 / 180 rotors). Note to Bike MFG's - if your bike is marketed at Downcountry (Trail Lite) and beyond, please spec with 4 piston brakes!
  • 1 0
 Some reasonably priced monoblock options would be nice too. Ever since the Hayes Stroker Ace was discontinued, anything with a monoblock designed caliper has become outrageously expensive.
  • 33 4
 Power isn't relative to number of pistons, and some value the relative ease of maintenance of a 2-piston opposed to a 4-piston. Ex. Hayes Dominion A4 and A2 produce the same power, but A4 has a larger brake pad which manages heat better with the same power, meaning you have the same amount of power but for an extended period relative to the A2.

Note to bike Mfgs: Spec Hayes Dominion!
  • 11 0
 Formula Cura has 24mm pistons compared to 22mm on XT. With properly sized rotors they offer plenty of power for a trail bike.
  • 6 28
flag Wthomas (Jul 22, 2021 at 12:49) (Below Threshold)
 2 piston brakes are garbage. 4 piston brakes are a lot safer imo because you can meter the power alot better. I run magura mt5 and I can’t imagine going back down to a 2 piston
  • 7 2
 I have a f/s trail bike with 200mm rotors and 4 piston Guides, but they feel as powerful as my 180mm Ice Tech equipped Deore 2 piston brakes on a fat bike. For the riding I do in NE, they're both fine. A lot of my buddies have 2 piston bikes and are around 180 to 200 lbs like myself and are never complaining about braking performance. These include lift access days as well.

My point is that while the 4 pistons have they're place, the majority of people don't need that much power.
  • 1 2
 If I was building up a super light, 18 pound carbon gravel bike I'd still put my 203mm rotor 4 piston TRPs on them (probably wouldn't be 18 pounds at that point....)
  • 5 1
 @NRZ: I agree. I've ridden plenty of light DH tracks on 2 piston brakes with no problems. Shorter tracks though, so I can't advise on heat management.
  • 7 3
 I’d say that putting a 4 piston brake up front is mandatory , but a 2 piston brake in the rear would be fine for most trail applications . Didn’t Magura do this?
  • 3 0
 @mountaincross: came here to post this. Truly remarkable brakes for a trail bike, especially when paired with a larger rotor up front.
  • 1 0
 @short-but-sweet: @short-but-sweet: Yeah and everyone hated/hates it because it's unnecessarily complicated to sell sets/spec OEM with non-matching brakes. Especially when last time I looked (granted it was like 2 years ago), they charged almost identical amounts anyway
  • 8 0
 @hamncheez: Lol what? I’ve got 2 piston TRP calipers with 160mm rotors on my steel gravel bike and it hauls my 200 pound ass down to 0 plenty fast. I can lock up both wheels any time I want on any terrain.
  • 4 3
 4 piston are more difficult to maintain. I'd rather go to maximum sized rotors before compromising to purchase 4 piston.
  • 3 10
flag AZRyder (Jul 22, 2021 at 21:03) (Below Threshold)
 @therealmancub: Power is relative to piston surface area. More pistons mean more piston surface area. If more pistons didn't mean more power most performance cars would be specced with cheaper and lighter single piston calipers. Not the case. And considering how many people agreed with your blatantly incorrect statement proves how many PB riders understand basic physics or engineering. Bunch of dentists with nothing but opinions lmfaoooooo
  • 1 0
 @Tracefunction: yeah. Well perhaps this is why I run codes !
  • 1 0
 @mountaincross: Agreed, with the CURA 2 pot, the power IS there, and they look nice, but personal preference that you have to pull them harder to get the power on tap was an issue for me...
  • 1 3
 @therealmancub: “power isn’t relative to number of pistons” definitely incorrect. Pb users should stick to their dental tools lol
  • 2 0
 @mountaincross: Iles rode them to at least one 2017 WCDH podium
  • 3 2
 @AZRyder: there's a Google spreadsheet kicking around the internet somewhere with piston and MC diameters/areas for a bunch of common brakes. Going from 2 to 4 piston doesn't increase mechanical advantage quite as much as people think bc the individual piston sizes are smaller on the 4 piston brakes. Some of the 4 piston units actually have LESS piston area than some of the 2 piston options. And the area increase you get from 4 piston is usually like 5-15% according to the measurements.

So anyway it's not as simple as "2 piston bad, 4 piston good". IME 2 piston brakes are fine for like 90% of riding. By the time the brakes start to fade I usually need to stop and relieve my arm pump anyway. But for racing / bigger bikes obviously it makes sense to have the little bit of extra power.

docs.google.com/spreadsheets/d/1sjPSmOYbhjDBFxcvXVw1ufKfowEBu1AKh8sB6T8e24Y/edit?usp=drivesdk
  • 1 1
 My original comment, should have been more clear as I was more referring to the surface area of brake pads on 4 piston vs 2 piston brakes... My real life example would be the 2021 XTR 2 piston brakes use the road size pads, which are roughly 3/4 the size of standard shimano 2 piston pads. The stopping power of the smaller pads is horrible. Never should there be road sized pads used on mountain bikes. Note, this is also using 180 mm rotors on a "Downcountry" / Trail Lite mountain bike. 4 Piston brakes are always using larger pads than their 2 piston counter parts. So, yes I agree that 2 piston brakes can be just as powerful, the surface area of the pads is a major factor in performance, much like going from 160mm rotors to 180 or 203...
  • 2 1
 @bkm303: hence my comment on increasing piston surface area. I get this may be something you don’t understand which is why you shouldn’t voice opinions on it. The point of even going to more pistons is to increase piston surface area. You could have two identical pads and one being pushed by more surface area. That one being pushed by more surface area will have a higher PSI rating over the one pushed by less piston surface area. Piston surface area and pad surface area have two very different effects. I can tell most pb’ers are ignorant af based on the lack of being able to decipher between the two.
  • 2 0
 @blum585: read my comment. Pad surface area and piston surface area are two different dimensions both having differing effects. A caliper with more piston surface area but identical pad surface area will always outperform due to its ability to produce a higher psi rating on the rotor.
  • 1 0
 @sjma: cool story bro!
  • 1 1
 @therealmancub: “power isn’t relative to number of pistons” easily the dumbest thing I have read in the past month. Tell that concept to brembo, willwood, stop tech or literally anybody that works in the braking industry. The fact that most pb’ers agree with this idiotic, ignorant, and blatantly wrong statement proves the market here is ignorant and shouldn’t be making engineering based decisions. Any automotive engineer knows that increasing piston surface area, ie more pistons, will increase PSI at the pad regardless of pad surface area. A great example is any automotive 4 piston brake setup. Most 4 pistons don’t even use a bigger pad, just more pistons. If your statement was even remotely correct, then the entire braking industry from automotive to motorcycle to industrial would all be wrong. Or is it maybe you and the rest of the know it all dentists are wrong?
  • 1 0
 @NRZ: cool story bro!
  • 4 0
 @AZRyder: not sure why you're replying like a condescending a*shole when I'm basically agreeing with you... mechanical advantage in the hydraulic system is a function of piston area vs MC area (and whatever mechanical advantage you're getting from the lever itself). Never mentioned pad area at all bc it's not really that significant (doesn't appear in the brake torque calculation at all, for example, but does affect wear rates & heat buildup).

My point is that yes, obviously more piston area = more power (holding all other things constant), but most of these 4 piston offerings don't actually increase the piston area by that much. Lots of people talk about it as if 2x the pistons means ~2x the power when really we're talking about a 5-15% increase in force at the pad.

Obviously this is enough to matter if you're racing, but there aren't really any trail riding scenarios where 2 vs 4 pistons means the difference between safe/unsafe or rideable/unrideable. So in the context of "why are mfrs still specing 2 piston brakes on any bikes".... it's because they're cheaper/simpler and unless the bike is meant for DH/park/enduro racing it honestly doesn't matter that much.

Btw “power isn’t relative to number of pistons” is absolutely correct. Two 1 cm pistons is less area than one 2cm piston. Maybe stop trying to prove how smart you are and actually read ppls posts.
  • 1 0
 @AZRyder: I did read your comment and I agree with you which is why I clarified why I originally made a comment. This community is pretty awesome... Not all two piston brakes are created equal...
  • 1 0
 @AZRyder: BTW Thank You for qualifying my intelligence - A paywall for comments might be a welcome feature in the future.
  • 4 0
 @bkm303: is this the spreadsheet?: docs.google.com/spreadsheets/d/1sjPSmOYbhjDBFxcvXVw1ufKfowEBu1AKh8sB6T8e24Y/edit#gid=0

@southoftheborder posted the link late last year and credited it to Udi at Ridemonkey.

My difficulty in accepting that the area of a 2cm piston is greater than that of two 1cm pistons is enough to keep me out of this overheated discussion
  • 3 0
 @ceecee: that's the one, thanks for crediting the source! Awesome bit of geekery to put all that info together.

Two 1cm pistons: 2*pi*1^2/4 = 1.57 cm^2
One 2cm piston: pi*2^2/4 = 3.14 cm^2
  • 1 0
 @bkm303: finally some actual data instead of the typical “I run two piston and don’t die so therefore it’s the best!” Y’all can leave your feel O meters at home. Real data or gtfo
  • 1 1
 @AZRyder: thx bro. 4 pistons are definitely sweet on bikes I've demoed but tbh my old SLX brakes aren't THAT much worse. If I was racing or riding park a lot I'd def pony up for some Maguras or something tho.
  • 1 2
 @blum585: your anecdotes don’t mean anything and your comparison of pad size to rotor diameter also doesn’t mean anything. Pad size and rotor diameter are two completely different factors that effect one another both completely differently. I get that’s something most riders don’t understand, which is why they shouldn’t be flinging their anecdotes around like monkeys do at the zoo.
  • 1 1
 @bkm303: again, more anecdotes. Save those for your mom lmfao
  • 2 0
 @AZRyder: last I checked I'm literally the only one in this whole thread that provided any hard data but ok
  • 2 1
 @bkm303: you posted one link with good information. Everything else was a BS story and some even more bs statements to go along with it. “Power isn’t relative to number of pistons” boy the rest of the engineers and I sure got a good kick out of that one lol
  • 1 0
 @AZRyder: power isn't dictated by number of pistons, not sure why you (and "the rest of the engineers") keep harping on that when you're objectively wrong. Piston AREA is what dictates mechanical advantage. As stated above (with math), two 1cm pistons are worse than one 2cm piston (half the area). It's not as simple as saying "more pistons = better". Do the math yourself.

You're making the rest of us engineers look bad... you're not the only one with a degree, and I'd be a little more careful about advertising that fact when you're making incorrect statements (and being a dick) online.
  • 1 0
 @bkm303: yeah I said that already “Any automotive engineer knows that increasing piston surface area, ie more pistons, will increase PSI at the pad regardless of pad surface area”. Thanks for publicizing your lack of reading comprehension. And you have a degree too? Lol Go hit the books bud!
  • 1 0
 @AZRyder:
"“power isn’t relative to number of pistons” definitely incorrect. Pb users should stick to their dental tools lol"

"'power isn’t relative to number of pistons' easily the dumbest thing I have read in the past month."

"“Power isn’t relative to number of pistons” boy the rest of the engineers and I sure got a good kick out of that one lol"

Objectively wrong, 3x in the same thread.

Where was that hard data you provided again?
  • 1 0
 @AZRyder: actually I missed one, make that 4x wrong:

"More pistons mean more piston surface area."
  • 1 0
 @bkm303: typically, when you add another piston, piston surface area is increased. I bet 4th grade was hard for you Wink
  • 1 0
 @AZRyder: typically but not always, meaning the people you were ridiculing were technically correct.
  • 1 0
 @AZRyder: for example, BR-M755 4 piston has less area than most Shimano 2 pistons.
  • 1 0
 @bkm303: the people I am ridiculing, aka you and the rest of the mouth breathers, just want to prove whatever minuscule point they have. “Well technically” well technically your comprehension is entirely ego driven and doesn’t rely on concepts or application. Increase piston surface area, increase psi at the pad. Not that hard of a concept. Obviously, given all the same other metrics (figured I’d specify for the mouth breathers) or we can throw all sciences out the window and I can tell you how I “feel” about extra pistons or how they “feel” on my bike lmfao
  • 1 2
 @AZRyder: Idk how your engineering works, but in mine being technically, quantifiably correct is what matters. Technicalities often determine whether a part/system meets or fails requirements.

"Increase piston surface area, increase psi at the pad"

Yes, which is why, based on the DATA in the sheet I provided, I stated that there's not that much difference in piston area between most 2 piston and 4 piston brakes, all other things being equal.
Guide vs Level (2.6%)
Cura vs Cura 4 (12%)
M810 vs M785 (6%)
X2 vs E4 (6%)

So it's completely understandable why riders and bike brands "feel" they don't need a 4 piston brake for normal trail bikes - it's a big cost add for a marginal improvement. And even if you do "feel" you need more braking torque, sizing up your rotors produces a bigger improvement for less cost. DH/Enduro/park riding are a different story and rotor size is usually already maxed out on those bikes, so 4 pistons are the obvious choice there.

You can have different "feelings" about your brakes, I'm sure you're running the sickest, most powerful Shigura setup anyone's ever seen.... But I still haven't seen a shred of quantitative data or productive, non-dickish discussion from you in this convo so I'm gonna stop here.
  • 1 0
 @bkm303: now you’re bringing up rotor diameter which plays on leverage, totally unrelated to pressure at the pad. Sounds like your “engineering” is confused and should take some time to decipher what effects what and how. Your convo stops there because your understanding stops there. Increase your understanding and you’ll be able to converse more effectively on the concepts at hand. Good luck!
  • 32 2
 With less travel I have a better excuse not to hit big features my friends do with their Enduro sled...'oh man, sick feature but on this trail bike I just don't feel comfortable hitting it'
  • 6 4
 Same… my wife would kill me if I came home to two kids under three with broken bones!
  • 7 0
 @StumpHumper45: They get used to it. My kids shuttle with me to the emergency room way too often, but they have the coolest stories to tell at school; "My dad almost lost his eye last night, there was.blood everywhere, but luckily after.stitching up his eyelid, everything was cool"
  • 5 4
 It's why I've been so hesitant to upgrade to a beefier shock. There isn't a lot of data out there about just how long of a intense, chunky downhill it would take to impact the damping of a non-reservoir shock, and even being a bigger guy I've only experienced it a few times on all but the longest downhills. Sure, coil shocks definitely are more plush, and I'm sure someday I'll need all the comfort I can get (my coil fork is awesome), but until then, I'm inclined to keep rocking the lightest shock that'll do the job 90% of the time.

The only time I think a big shock really matters is big drops and shuttle/park days.

Here again, it's a perfect use case for two options. Get a nice air shock for daily riding, and a cheap coil for park days.
  • 2 1
 @PHeller: I agree! I watched something from Suntour and they explained the same thing about Piggyback shocks. They straight up said most riders don’t need them for their riding. Mtb marketing is all about selling us stuff that we think we need!
  • 2 0
 @PHeller: I would tend to agree, at least for trail duty. I upgraded my Monarch RL to a Plus RC3 (Piggyback) because the RL was always squeaking after services and I convinced myself that the performance on long downhills was changing. Turns out the RC3 gave me more problems and not a measurable performance difference. What made a HUGE difference was upgrading to a CC DB Air IL (non-piggyback) with Hi/Low Comp/Reb adjustments. Unbelievable difference in support and rear end feel. Aside from insane cane creek service prices I'm super pleased with the shock. Somehow feels livelier, grippier, and more supportive (not blowing thru travel) all in one shot.
  • 28 2
 I thought it is rotation wheel weight and unsprung suspension weight which truly affect performance... anything outside of those areas is purely mental/aesthetics on a trail bike, no?

PS - if you want to drop some serious weight on your bike.. take out all the batteries. Wink
  • 7 0
 I agree! Rotating mass counts with the power of 2 and unsprung mass is really important in terms of performance. And for hardtail-riders the weight of the frame is unsprung, because the back wheel has to be lifted over all obstacles... So it's important to take care for the differences in this discussion too.
  • 3 0
 Currently riding a 2021 Giant Trance X 29 2 - (SLX/DPS/36). Rebuilding the wheels and changing tires dumped over 600g of rotating, unsprung weight - and way cheaper than getting a carbon frame to achieve the same mass reduction.
  • 1 0
 You don't need to worry about the weight if you have batteries in it..
  • 1 0
 Yes but rotational weight is also good weight. The gyroscopic effect helps maintain lines. I don’t mind a bit of extra rotational weight when my speed increases. It’s only on slow grinding climbs that I find it to be a negative.
  • 29 1
 Taking a dump before your ride pushes you from XT to XTR!
  • 2 0
 Underrated comment. Basically everything atop the sattle. And yes, there are exceptions to the rule.
  • 6 0
 Ok but what if I have XTR and then take a dump before I ride?
  • 4 0
 @MegaStoke: then you fly away
  • 22 1
 I dont get it. Title is where to save weight on your bike, but through whole text hes talking about adding burlier components instead of other way around!?
  • 9 1
 exactly - he doesnt even answer the question.
  • 3 1
 @Brdjanin they gave the lighter /lightest reasonable option (for a trail bike) and compared them to what most people choose from, or get. It made perfect sense to me.
  • 21 0
 Boy oh boy, is @dangerholm going to be mad at you for not stating the obvious answer "yes."
  • 10 0
 I recently swapped frames, from a full carbon setup to alloy. I kept all of my components from the full carbon setup, which are fairly high end (X01 drivetrain, Factory 36, carbon wheels with CushCore and Bontrager SE series tires, carbon bars, etc.). The move to alloy was a lateral move for me, as it was based off the geometry of the bike and the lack of a carbon option. Overall, it's pushed me from roughly 32.5 lbs. to 34.8 lbs. and I couldn't be happier.

I focused heavily on what I liked and disliked on my carbon frame and searched for the best match, regardless of material. I now have an alloy frame that has a better seated pedaling position, as stiff or stiffer frame in relation to the BB/suspension area, and a taller stack so I sit a little higher, and longer chain stays help place me more center on the bike. Not only can I pedal uphill just as good, but I feel less tired and I can descend even faster.

A little bit of weight has it's advantages if you know what you're looking for.
  • 1 0
 Out of interest, what frame did you swap from and what did you swap too?
  • 1 0
 @SamCoffey: I went from a 2021 Fuel Ex frame (was a 9.9) to a Banshee Prime v3. Both have the same reach and near same rear travel, but the Banshee is a much better performer while climbing in the saddle and when descending.

The Fuel has a very low stack height and short stays. I was either very leaned forward when climbing while seated, or weighting the rear of the bike too much when descending. It was still a really good bike overall, and I will admit, it could get up and go when you got on it, mainly sprinting, but when seated and pedaling the Banshee is a dream. Plus the Banshee descends WAY better.

I also re-weighed the Banshee with a proper scale -- 34.04 lbs. Not bad for a beefier alloy bike.

The Banshee has the
  • 9 1
 I like the extra 4-5lbs on my trailbike (21' Meta AM29)....so I don't need to look for weight savings

At 37lbs it feels way more stable and sure-footed in the steep, fast, rough sections - the sections that I love. Ya its tougher to pedal up but I dont mind.....I only climb to go down.
[Reply]
  • 8 0
 The priority should be where the weight is - lower centre of gravity is better.

If I drink lots of beer, I kill brain cells. This makes my (high up) head lighter. It also makes gut hang out and down, further lowering my centre of gravity.

Drinking beer FTW.
  • 8 0
 Bike weights are getting back to the freeride era. 6 years ago an enduro bike was actually pedalable. Now Enduro bikes are "pedalable for a bike with 180mm of suspension". Theres a big difference. Its fine, but can we quit saying a 180mm bike pedals well? Because in reality it pedals like shit compared to a trail bike, which now is 140-150mm average anyway.

What the f*ck happened to us!
  • 7 0
 Lightweight feel pretty much comes down to tire selection in my experience. WTB Vigilantes, Maxxis High Rollers, and Michelin Trail AM's are the grippiest tires I'll run. DHR, DHF, and Magic Mary's take away too much speed potential on climbs and easy trails IMO for a trail bike.
  • 2 0
 Agreed. On my daily grind, I love fast rolling tyres.
  • 7 0
 I thought I didn't care that my Capra weighed 36lbs until I built my Tyee out to 30lbs. Close enough capabilities on the DH but way more fun, flickable and rideable all around. That said, we have nasty climbs and pretty rough descents. I'd argue if someone's typical riding is somewhere more in the middle, then it further justifies a lighter bike. That said, go middle (durability/capability/weight) with components and lightish with frame (because you can't change that).
  • 14 0
 Don't come round here with your balanced and sensible approach to real life MTBing. Of course the real lesson here is that you need more than one bike.
  • 1 0
 How do you like tyee, and propain’s support..? Im now on canyon but will be looking at a new bike in a year or so and tyee or hugene look rly nice on paper…
  • 7 0
 When did 34lbs, lyriks and DD tyres with inserts become the norm for a trail bike? A trail bike is one step up from an xc race bike. It should be mid 20's, 120ish travel, light enough for long days.

If you need a 160mm 29er to ride your trails, you are either racing (in which case, go for it), or you should spend that upgrade money on coaching..
  • 2 0
 These are discussions out of scope for this article and hard reality for most mtbers
  • 1 0
 My trail bike is 40lb. I guess it depends on your definition of a trail bike. For me it's everything between XC bikes and DH bikes. Enduro is just a type of racing / style of riding.
  • 7 1
 Why does this article claim the Fox 36 has a minimum travel of 150mm? I have mine currently at 140mm, and many bikes come with a 140mm Fox 36 (Pivot Trail 429 Enduro, for example). Yes it is hard to buy a new 140mm Fox 36, but very easy to buy a 140mm air shaft and install it.
  • 2 0
 Exactly. I thought this too. Changing air shafts is no big deal
  • 1 0
 Yes, my Fuel Ex has a 140 mm 36.
  • 1 0
 @shepridesbikes: Hehe, my Fuel has a 140 mm 34. Never thought of myself as a weight weenie until this moment.
  • 1 0
 I believe that 36 with 140mm only comes as OEM part of the bike. How much I saw 150mm is minimum travel if you want to buy fox 36 separately.
  • 1 0
 They also state Pike tops out at 140 for a 29er, I have a 150 29er in my garage I bought stock.
  • 10 1
 Wanna save weight and moneys? Go 11 speed.
  • 6 0
 We need the 10-45 cassette 11 speed cassette.
  • 2 0
 @TerrapinBen: sunrace make a good 10-46t 11sp cassette in XD format
  • 3 1
 @chakaping: And weighs at least 1/4 pound more than an E13 and 1/2 pound more than an XO 11 sp
  • 2 0
 @Joecx: but it's still a decent weight and cost me 85 euros. No brainer for me.
  • 2 0
 @chakaping: pity it weighs twice as much as the XG1195, but it is a good budget option.
  • 1 0
 @miuan: But that's at least twice the price and only 10-42t.
  • 1 0
 @chakaping: For me, the sunrace cassette weighs too much to be a viable option for my trail/enduro bike. 10 - 45 XD compatible eleven speed is awesome and what I want, but while the sunrace is affordable it is also a boat anchor.

I think the ultimate goal would be a 10-45 11 speed cassette that weights around 300g and doesn't cost a fortune. It's good to want.
  • 2 0
 10 speed 11-36 cassette. It's lighter, cheaper and makes you fitter therefore faster. Winner winner chicken dinner.
  • 9 3
 The first thing to upgrade is your endurance and strength. If you’re in “I like to ride and drink beer” shape and don’t train for endurance and strength, then your bike is going to ride as mediocre as your are.
  • 4 0
 Making a heavy bike light by changing components is most costly option. Better save your pennies and by a new complete bike earlier with the weight you are aiming for.
The only (rare) exception is when you have a light bike except one or two really heavy components that aren't expensive to swap.
  • 4 0
 My advice is upgrade your parts as they wear out. Better performance and usually a little less weight. Counting grams only is what serious racers do, the rest of us are better off getting better equipment to enjoy the ride more.
  • 5 1
 You forgot the most important parameter: the riders weight. Cut on a diet, throw off some pounds and you have saved a few greens in your poket. The weight on the whole counts- it is still yourself that you have to drag up that mountain. So why not start with the pilot instead of the machine?
  • 4 0
 What's the point if Trek keeps pushing for bigger wheels and therefore bigger tires and SRAM keeps pushing for bigger plates for their cassettes? All other parts are pretty miniscule compared to the size/weight of the wheels, tires, and cassette.
  • 5 0
 I think that when it comes to travel, one should match the terrain you ride generally and your skill there's a lot of overbiking out there!!!
  • 5 0
 I remember when pikes where being specced on everything from 110mm xc trail bikes to enduro machines without issue… just sayin
  • 1 0
 There was a 110mm Pike? Huh, did not know that.

I run a Fox 34 SC 120mm on a "downcountry" bike (is that what we call them now... lol) and it's great. It's basically an XC bike, with somewhat slacker geometry and fit.
  • 1 0
 Yeah it wasn't that long ago that everyone thought the Pike was a super stiff/capable fork that could do it all (hint - that's still true). No way I'm putting a Zeb or Lyrik on a bike unless it's just meant to ride lifts/shuttles most of the time. If you're not running 170mm of travel I just don't see the need for the added stiffness.
  • 4 1
 Its been proven more than once that weigh (in resonable amount) doesn't effect the performance on a bike much at all. Still, people like to spend there money on expensive light weight products. I guess that makes them happy, for the moment.
  • 4 1
 People have an easy time thinking their bike is too heavy so that's why they're slow and can't jump. Much easier than admitting they're just fat
  • 2 0
 @Tracefunction: Sadly, for most people It's easier/makes more sense to pay money to lose weight on a bike than lose weight themselves and have to change/compromise their lifestyle
  • 2 0
 I would disagree that weight does not affect the performance.. it does.. but if you dont race you just dont feel the performance difference that much, it is still there, just does not affect your impression of a ride.. you wouldnt argue that “hp/torque dont affect car’s performance” just because you drive in a bumper to bumper city traffic..
  • 5 2
 Thought experiment if weight is evil:

1. We should all switch to helium in our tires, it will actually make your bike lighter! Too lazy to do the math
2. We should not put grips on our handlebars and just wear thicker gloves, infinite reduction due to dividing by zero
3. We should all go back to riding 26" bikes that are too small for us ( 29er is dead!), ligher wheels' lighter tires, lighter frames.
4. Not bring any water and just drink from puddles and streams or crushing it out of plants. Secondary benefit of weight loss when you get sick from drinking contaminated water. Ok this doesn't really make the bike lighter but imagine the benefits!
5. Remove all branding and fancy finishes on your bike. These are pure vanity and free advertising for others. Use the thinnest coat of the lightest colour paint ( I seem to recall white pigment is actually one of the lightest for paint)
  • 15 9
 Could just save on outside+ ?
  • 3 2
 A way to lighten the wallet. Definite weight savings.
  • 3 0
 I try not to weigh my bike, I buy mainly based on how it rides. However I do compare component upgrade weights when I buy those, but the overall weight of the bike doesn't matter as much as how it feels on the trail.
  • 2 0
 On an XC or a road bike, sure....go ahead with some weight savings. I've done it and yeah, it does help improve performance, in a couple ways.

I've ridden two different Sights this past year with two different carbon wheelsets:

29er WAO Union wheels....strong as shit and got through a season running no cushcore. No dents, cracks, etc. 9 months of hard riding.

27.5 DT Swiss XMC 1200 wheels...strong, yes....but also weighs about a full pound less than the WAO wheels. Cracked the rear in less than 3 months. Cushcore in for the last month.


The DT wheels are also about $1,000 CAD more than the WAO wheelset and I still have to pay $400 + for a new rear wheel.
  • 3 1
 I expected to be quicker moving from 26" to 29" wheels. Larger wheels have ~11% great circumference right ... so must be faster??

Expect I wasn't. On non-technical smoother climbs (fireroads), smaller wheels had the speed advantage. But technical climbing was speedier on 29". I didn't account for pushing the increased rotational mass.

Associate prof in Physics:

"So yes, adding mass to the wheel is worse than adding mass to the frame---but only when accelerating. Still, every little bit helps." All of the gory details and science from his article is here:

www.wired.com/2016/06/cycling-physics-extra-mass-bike-wheels-enemy

BTW, the best way for me to lose weight on the bike is to shrink my body. IE keep a careful diet, get enough sleep, lifts the occasional weights and of course ride and ride.
  • 2 0
 His assumption where all the weight is as the rim can mislead. Where the weight is in the wheel matters, too. You aren't penalized nearly as much, if at all, for weight at the hub compared to the rim (ignoring the argument of sprung/unsprung weight). I think most people don't understand that, or that a heavier wheel can potentially accelerate better than a lighter wheel, pending where the mass is located across the wheel.
  • 1 0
 @privateer-wheels: I agree that weight in the hub will not matter too much.

Based on your business, I guess you've spent a considerable amount of time thinking about this. My hunch would have been the bulk of the weight would always be in rim / tire, vs hub–to the point that hub weight is negligible.
  • 3 0
 @njcbps: many people will avoid slightly heavier hubs and sacrifice low drag, more robust and quicker engagement, and better sealing, simply to save a few grams. It never makes sense to me as those hubs may legitimately offer efficiency gains that far outstrip any weight gain. Onyx comes to mind.

I have a great video reposted on Insta from GRS engineering that shows two wheels of the same weight with different weight distribution, clearly accelerating at different paces. It's a great illustration of this. Have a look!
  • 2 0
 My Grip 2 Fox 34 is 1940g without axle. The 36 is like 2000g so there's no point in a 34 anymore unless you get the FIT 4 version. Also you can still get air shafts to make the 34 150mm.

If you want a trail bike coil, you get a Cane Creek DB Inline, not a DHX2.

I don't know why you would pick Nukeproof in a discussion on weight. Maybe you are clueless? It's hard to know these days.
  • 2 0
 Agree the 34 only really makes sense in the lighter fit4 shorter travel setup. Weighed a 2022 130mm 34 29 at 1700g with uncut steerer and kabolt axle (same weight as old step cast).

That said I don't think any newer 36 is 2000g unless its fit4 650b. My 21 36 grip2 29 is ~2200g with kabolt
  • 1 0
 @lyzyrdskydr: I don't have a 36 or 38, but that is very interesting that your 36 is 2200g because Enduro-mtb mag reported their 29er 2021 38 170mm Factory Grip 2 to be 2213g. I guess we can just eliminate everything between the 34SC and the 38, just no point to them really.
  • 1 0
 @JohanG: That must be without axle and star nut, most other outlets including Pinkbike weighed the 38 at ~2400g. Never weighed one myself but I've installed a couple and they are noticeably heavier than a 36.

Don't pay much attention to weight on my bigger bikes, just have no need for a 38. The newer 36 is a huge improvement over the last one and my favorite fork to date. Plenty stiff even a 170/29, if I ever wanted a burlier fork I would look at dual crowns
  • 2 0
 Never ever weight my bikes,so no clue if it is heavy or not. But 9 years of lifting bikes on to a trailer as an uplift-trail guide guy:
First DH bikes,heavy has f*ck but my local trails where so gnarly and ugly any trail bike of that period would break in peaces. It was a pain in the back lift 8 bikes to the bike trailer over and over.
Then first gen enduro bikes,very light but flat tires everywhere. If was fun to challenge my boss and the other workers to clock the inner tube swaps. Since then, I can do it eyes closed it no time...
Now you have a mix of e-f*cking heavy bikes and beefy enduro bikes on the trailer. Some times I struggle to lift and place by my self some fat tire e-bikes. Those bikes almost weight half of me.
  • 2 0
 Unweight unsprung mass as light as will survive on your "trail bike" The rest is a bit meh but I can say my previous 12.5kg trail bike was way more fun as a trail bike than it was as a 14.5kg thumper on trail bike trails. I recently changed my enduro 29er back onto lighter XM481 rims and lighter casing tyres. Way more fun and lively in a heap of places and all I do in genuine high speed chunder is ride lighter (like I am on my hardtail in some ways). I still have a heavy wheelset with stronger casing for shuttles and can really feel the difference straight away particularly in rear suspension action with all the extra unsprung weight. Ultimately I reckon I will build another light trail bike, and turn the big bike into a true shuttle bruiser.
  • 3 0
 Rims, tires, and cassette weight are going to make the biggest difference. Not only do they represent rotational mass, they also directly impact the function of suspension. This should be on your mind, even on an enduro bike
  • 2 0
 There was a time when weight trumped quality. This is still the case with forks. No need for loose CSU,s .
Trying to make carbon fiber frames a pound lighter than aluminum. The result. Frames that failed in less than two years. Now carbon fiber frames weigh the same , look at Norcos new bikes , as aluminum.
There appears to be too much guessing about strength to weight ratio. No wonder its very popular to change the frame every year to a new design.
If a frame works well than why not keep improving that frame ? Refine the strength to weight ratio.
Change for the sake of change. That appears to be the marketing strategy.
It's possible to make strong light weight parts. That last . But if that part changes next year how do you gauge longevity?
Glad I'm not riding 29 inch wheels. The larger diameter puts much more stress on the frame and fork and you have to live with very heavy wheels unless you invest in 2000 to 3000$ wheels . But if you want proper traction and support from 29 inch tires than the tires will probably start at about 1200 grams.
Smaller wheels require more skill they require a greater level of concentration. That's what I want. Smaller wheels are easier to turn, easier to flic. Easier to lift. Much easier to build strong and light.
We are talking about trail bikes to me that's long distance riding with plenty of climbing and desending.
I want a light bike.
Enduro racing heavier bike.
  • 6 5
 I find it interesting to note that the article never articulates *why* one would care much/desire a bike that is, say, 29 pounds instead of 31.

If you're going to count grams, you have to be talking about the full vehicle weight (ie, with the rider). Changing the fork by 200g or whatever is only going to be ~0.2% or so of the actual vehicle weight (~90,000 grams with an average adult male/average trail bike). And unfortunately you (and I) have to haul our fat arses around with our bikes when we ride.

Does it matter? Kinda. But not very much. 200g sounds like a big number but it's just dwarfed by the rest of the weight you're dealing with and the other (rolling resistance, drivetrain losses, air resistance, etc) stuff you have to overcome. If you are really bored you can cruise to analyticcycling and figure out how much faster you can go on Ventoux with a 75g lighter set of pedals or whatever. You might be surprised how little it matters.

-W
  • 4 0
 It’s clearly quite a personal thing but light bikes ride great for me. Maybe strength plays a part too?
  • 3 1
 @johnny2shoes: I know. I have a Ripley LS, with MRP Stage at 26 pounds with DHF/Ardent Race combo for my trail bike. I don't feel a need for any heavier parts. Then again, I enjoy going fast up as well as down. I try for KOM's on loops on that bike, rather than just the climbs or descents. Though sometimes I'll pick one up on a climb, or get in top 10 on a descent. Rarely top 10 for descents anymore though, can't keep up with the real enduro bikes. Doesn't help when they hold a race on your local trails and some seriously fast guys rip up the segments. Still get up there for some full descents though, since I'm not stopping and resting between segments.
  • 2 0
 One thing to consider is that if you travel with your bike you can avoid overweight charges if you can get the bike and carrier 50lb or 23kg in Europe. So, I like to have a bike that is sub 30 lbs without the pedals and rotors(sometimes cassette and seat). EVOC bag is 20 lbs. You can save $300-400 round trip. Helps justify some of those light parts.
  • 2 2
 I built up a light "all mountain" bike, 160/160 Cube Stereo 27.5. It was 26-27lbs with pedals and good tires. The geo was a little silly, but it was a lot of fun, shouldn't have sold it. Then the scamdemic happened and you couldn't get the light cube or radon frames. The thing was 2300g with axle. After a few hours of technical rocky terrain and ledge ups, you appreciate the light bike. Of course it isn't for smashing things at high speed.
  • 3 2
 "Of course, the slacker the head angle the more it requires in terms of stiffness."
Is that really a self-evident truth with regard to forks? Why?
If it's because you're going faster then maybe, but I don't see why the slackness itself would require a stiffer fork.
  • 5 1
 There is an angle beyond which you start getting bushing bind into the travel if the stanchions are flexing
  • 1 0
 @JimLad: this angle is roughly 90 degrees. Anything below will bind the chassis to a certain extent.
  • 1 0
 @Muckal: that depends on the shape of the incoming bump. Anytime not normal to the fork axis will induce some flex and depending on the chassis that flex will be enough to cause binding
  • 1 0
 @JimLad: exactly.
  • 2 0
 @JimLad: I understand bushing binding is always cited as a theoretical issue with slack bikes but I'm not convinced it's an issue in the real world.
I've slacked my trail bike out to sub-63deg HA and only good things have happened.
I seem to recall hearing Chris Porter say it wasn't really an issue on his recent NSMB podcast, which surprised me actually 'cos I thought he'd always had a bee in his bonnet about it before.
  • 1 0
 @chakaping: if I recall Fabien Barel was testing back in the day, and 61-62 degrees seemed to be the maximum. Sub 60 was a no go. That may have also been due to effects on steering though
  • 3 0
 @JimLad: we need Pinkbike to get some proper testing done on the grim donut.
Now there's a tech article I want to read.
  • 4 0
 Weight vs performance vs longevity. I'll choose longevity and performance over weight every time.
  • 2 0
 ended up having to go with the 36 on my new altitude build since the 38 was not available till next season. I am sad I don't have the popcan stanchions, but yet again at 150 lbs, these things are likely all I will ever need.
  • 4 0
 Go singlespeed. Save 1200 to 1400 grams and probably lose some of your own weight too....
  • 3 2
 I think there is a relevant weight to improvement in performance with upgrading from Fox34 to Fox36, as the 36 performs significantly better in all conditions and the incredible flex in the 34. That said, I'd happily run a Pike over Lyrik and received the benefits of the reduced weight in a fork that is only marginally less burly than the Lyrik.
  • 1 0
 My trail bike is a YT Izzo Blaze with the following upgrades.

We Are One Union wheels with I9 Hydra hubs
Oneup Components 35mm rise bar with Ergon GE1 Evo Factory grips
Absoluteblack 30t chainring
Ceramic/metallic pads on the rear
Maxxis EXO Assegai on the front
Tannus tubeless armor insert in the rear
  • 3 0
 Want to save weight? drink your water before the ride and skip the frame mounted water bottle.
cage and water bottle together saves 800g.
  • 6 0
 What if I told you that water in your stomach weighs the same as water in your bottle?
  • 1 0
 This is totally subjective and depends on what you are trying to get out of the bike. Are you a racer? Is this your one stop shop bike? How much climbing do you actually do? Each goal has a different ideal build, that's up to the rider to decide.
  • 1 0
 My ride STOCK was 22lbs (size L S-Works Epic Evo). I can say for certain (for me) I am faster on the new bike than the old bike (XC, of course) - could it be all in my head? Certainly. Does that bother me? Nope -

I did add some weight to it (dual lock Fox 34SC and Fox DPS rear)..but, the lock out has rewards that far outweigh the weight.
  • 1 0
 How much does it weight now, with pedals and bottleholders?
  • 3 0
 It's 2030, Fox has phased out the 32 and 34. The 36 is limited to 120mm of travel, 38 only goes up to 160mm, you have to get the new 48 for extra stiffness.
  • 1 0
 What about weight saving between carbon and aluminum frame? I am surprised that was not discussed. Though I have been riding carbon for some years I am thinking of going back to Aluminum, primarily because almost all carbon frames out there cannot be recycled and that’s a huge bummer from the environmental perspective. Also, carbons break.
  • 4 1
 I try to save weight anytime there is no noticeable compromise in performance.
  • 1 0
 My old trail bike weighs 28 pounds - still going strong My old DH bike weighs 35 pounds - still going strong I still love and have fun riding them, cheap to maintain and weigh less than many new bikes
  • 4 0
 My head hurts reading all these numbers
  • 4 0
 First picture - passenger mode !
  • 3 0
 last time i lost my bottle off the bike frame, the bike felt amazing, until I was thirsty.
  • 2 1
 Heavy bikes & bikes(& cars)SUCK!!! Manufacturers NEED to learn to get performance from light parts instead of taking the easy way out & conditioning customers to accept it... -_-
  • 2 0
 Exactly. Every branch of sport spends a huge amount of time and money making their car, motor bike, running shoe etc as light as possible because it increases performance. Why does mountain biking think it’s different to every other sport
  • 2 1
 @CM999: I am really bothered by it... Especially I am the type of rider who adapts to terrain instead of forcing my bike to ride fast through all terrains - which is unreasonable to me... Why speed through rocks, roots, bumps etc, when you're not racing? Would you use low tyre pressures for more grip if you're not at a drag strip? Mountain bikers have gone too far in doing what the racers do\buy - & I blame the companies who benefit from saving money(by having a larger market for their products) & getting more money(by convincing the general public they need to use what the racers use when they don't)... We don't need heavier tyre casings, larger wheel diameters, & steeper head angles - we as regular consumers need to know our limits, use discretion & ride on less demanding trails......or......just slow down when you see ruff bumpy terrain & only speed when it's smooth & safe... O.O #ComeOnPeople
  • 1 0
 I like to swap out any large steel hardware for Ti also, light wheels an tyres are important for me. But, there is a trade off with tyre inserts an having the right tyre carcass for the conditions.....
  • 2 0
 By chosing the right wheels and tires you can save 2lb off the bike where you will feel it the most. That’s a huge change and for 90% of riders still plenty strong enough
  • 1 0
 My weight fluctuates ten pounds up or down every couple months. I notice a couple pounds off the bike much more than I notice when my weight fluctuates. It's not the outright speed, it's the overall handling of the bike.
  • 12 11
 Nothing on sprung vs unsprung or even mentioning of rotational weight. This article sucks and seems to be tailored to all the dentists out there lmfao
  • 2 1
 Its costly but the savings you can get from lighter cranks, chain, and cassette is pretty huge. Same with quality allow wheels compared to stock, which most mid teir spec'd bikes come with pretty heavy ones. I'll stick to a heavy shock and a 36 and upgrade the parts listed above.
  • 3 4
 subscribe to pinkbike+ for an article with actual information
  • 4 1
 Funny you’re being downvoted. Well, actually it’s perfectly sensible, PB community has always been full of clueless gapers, and even more joined our sport over the past year.
  • 5 3
 People thought I was crazy when I put a Fox 34 with a 160 airshaft on my Ripmo. The bike is much more playful and fun now.
  • 17 1
 We still think you're crazy.
  • 4 1
 @jeremy3220: Haha! I weigh 140lbs. I think it's going to be OK.
  • 2 0
 I hear your crown cracking in the woods!hahahaha.
  • 1 0
 Nice. Pics?
  • 1 0
 I've always prioritized rotating weight for pedaling and front end weight for front wheel lifts. Most other bike weight is pretty fungible.
  • 1 2
 I find DH specific component's tent to live entire season of the part riding without maintenance headache, punctures vented rims and other bullhsit;

In case your pedaling uphill limited close to none, it is worth going that route;

I barely can imagine spending week in bike park resort and smash you light carbon wheel in first few days - vacation wasted;
however for. local trails that you ride up and down - as light a possible to have more lap's
  • 5 0
 What?
  • 3 0
 Does the Pike top out at 140 in the 29"? My 2020 is 150mm.
  • 3 0
 Should be 150mm yea
  • 1 0
 Carbon bars are a good place to start with weight saving, because the performance difference is not noticeable: cue big fight about damping and stiffness!!!
  • 2 0
 "Trail biking is a broad catagory [sic]"

I wonder if Outside will hire y'all a proofreader...
  • 2 0
 If you can afford it getting some carbon bars and or cranks would also go a long way
  • 1 0
 My bike has lighter cranks, cassette and handlebar then came with the bike. All that weight savings was lost by running dh tires.
  • 1 0
 This was really interesting. Thanks! I also would have like to see what each piece of the drivetrain adds up to, like whats the most efficient combination of price/weight?
  • 1 0
 Always best to save weight on your butt, thighs, midsection, and for some of us great big dirty man breasts XD. Eat healthy, stay fit #1. Speaking 4 myself here.
  • 2 0
 Cranks and cassette if you want to spend money. The rest is what it is
  • 2 0
 Ok, in all the bike! Thanks!
  • 1 0
 I added weight to my AM bike and the confidence on the bike has gone through the roof.
  • 1 0
 I currently tailor my bike by 3 factors. 1 what i can afford. 2 what is in stock. 3 What works on the terrain i ride.
  • 1 0
 my 34 is a 150 so you're wrong. do some research before writing anything would ya
  • 2 2
 I don't think it is. The lightest bike I've ever owned was by far the worst. Give me some heft anyday.
  • 1 0
 I like to eat less. And take a dump before I ride.
  • 1 1
 I would add mass at near the BB by installing a motor and a battrey as the say in the UK
  • 1 0
 only things that matter imo are tires and geo....
  • 1 0
 I'd get rid of the motor and the battery - my bike is a pig.
  • 1 0
 They make a 130mm air-spring for the 36
  • 1 0
 not about to extract my Magic Mary front and Minion SS rear. Both 2.35
  • 1 0
 saving the weight of a rear shock.
  • 1 0
 Garbaruk cassettes and Ashima brake rotors help.
  • 1 0
 I’m not a weight weenie
  • 1 0
 Not having 1L of sealant in each tyre....
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