SRAM's 12-speed Eagle proves that a one-by drivetrain can match or better the range of a multiple-chainring transmission, which in turn, has doused any hopes that the front derailleur's smoldering embers will ever be rekindled. Eagle was a must for the Chicago-based parts maker, because its premier XX1 ensemble could not match the range of Shimano's sharp-shifting two-by drivetrains, and descriptors like "virtually," "similar to," or "nearly," are not the vocabulary of a winning team. The addition of a 50-tooth cog to its 10 by 42, eleven-speed cassette provides a 500-percent gearing spread, which exceeds Shimano XTR and XT's ranges and thus, should silence all doubters, even the staunchest two-by holdouts in Germany. That twelfth cog, however, may have consequences that reach beyond range and MSRP.
Eagle has only been released at present to a handful of media, racers and OEM customers for evaluation, but all reports have been quite positive. And, in spite of the expected pushback from potential customers who have grown weary of SRAM and Shimano's the cog-of-the-month competition, those who have time on the group have unanimously applauded SRAM for extending the lower gearing range to accommodate fitness levels that fall below professional athletes, without sacrificing top-end speed.
Less advertised, but perhaps more important, is the fact that improved frame geometry, advanced suspension and wider, grippier tires have made today's mountain bikes far more capable climbers, especially in technical situations, where the rider's legs and lungs have become the only limitations to topping ascents once deemed impossible. I am sure that Eagle will be embraced by the sport's strongest athletes when they begin to push those boundaries.
Shimano will be forced to respond, at least with a larger cassette cog, and we anticipate they will also jump to 12-speed as well. Shimano will offer a 46-tooth option and, because their present cassette design restricts their smallest cog to an 11-tooth, barring a new driver design, there is nowhere for Shimano to go except for up. Shimano fans who do not want to wait for the next iteration of XTR can jump ahead of Japan and purchase OneUp's Shark kit, which updates the cassette to a 10 by 50 to equal the range of SRAM's Eagle, and it updates the rear mech with a longer cage in order to handle the extra chain and new cog diameters.
The bottom line is that Eagle is destined for success, and in a short time, we will get used to seeing larger cassette cogs, just as we have learned to ignore wheel diameters and boost-width forks. That said, the acceptance of Eagle will also mark the time when the industry walked away from two hard fought improvements - both of which had profound effects upon the dual-suspension trail bikes we have recently come to know and love.
The first victim is the mid-cage rear derailleur. The long-cage rear derailleur was a product of the industry’s adherence to the triple crankset and the huge amount of chain take-up that it created for the rear derailleur. Riders hated them because the low-hanging cage reduced chain control and made the derailleur susceptible to damage. Switching to two-by drivetrains and later, SRAM's introduction of XX1, made it possible to reduce the length of the cage and the mid-cage derailleur finally became the industry standard. With the debut of SRAM's Eagle and Shimano's extended-range XT and XTR come some of the longest rear-derailleur jockey cages in the history of the sport.
The second loss is more difficult to explain, but it begins with a guy named Bob Girvin, a pioneer suspension designer who patented the forward pivot location of a bicycle's swingarm near the top of a 34-tooth chainring. One quarter century later, nobody has found a better location. Chain tension and the angle that the chain pulls from affects the suspension and how the suspension feels under pedaling loads. Girvin's compromise was to stabilize the drivetrain when it was in the middle option of the triple-cranksets everyone used back then. Girvin knew that shifting to the larger or smaller chainrings would adversely affect the suspension's kinematics, which is a problem that also gives present suspension designers headaches.
By accident or by design, SRAM's XX1 and its derivative one-by-eleven drivetrains stabilized the relationship between the chain and the rear suspension by fixing the size of the chainring almost exactly where Girvin placed it and the XX1 cassette encouraged the rider to keep the chain in the most neutral range of angles in relation to the rear suspension. Shimano's present close-ratio two-by cranksets also maintain that relationship. It can be argued that, in the past three or four years since the relationship between the drivetrain and the rear suspension has been stabilized, almost every long-travel bike made has been a good performer. The trend toward huge cassette cogs may unfortunately reverse that problem by exaggerating the chain angles, and could play havoc with the suspension kinematics once more. In support of Eagle, the angular chain component only occurs when it is shifted into the largest cogs, but those are also the moments when power output, control and grip are highlighted most.
It will be interesting to see how all of this ends up. Suspension designers will be able to tweak their kinematics to compensate for the changes, if needed, and rear derailleurs are pretty robust these days. I find it questionable, however, that after working so long to attain a stabilized drivetrain and instigate the mid-cage rear derailleur standard, that we would throw away both without a care just to widen the bike's transmission ratios. It’s worth considering.
TIL some cool new technical hx of gearing and bike kinematics. Thank you!
@richardcunningham, though I joke, do you see these changes accelerating the R&D of gearboxes? Or do you feel that these are not feasible and the new challenges of the 1X(insert double digit here) will have greater attention?
Seriously SRAM and Shimano, stop thinking short term and gives us gearboxes in different price ranges. You will make money on spare parts for gearboxes also!
At the same time, the whole world is looking at these drivetrains thinking they need to make a better one, not a new solution... So things may take some time.
Interesting read though, I enjoyed this whole thing
@Raffe this, along with the concentrated mass low and center on the bike, is reason enough for me not to go back to derailers for anything where I am concerned about downhill performance. It's mind blowing how much better the suspension feels without an extra pound or more of weight on the rear axle. Weight that isn't rotating, and some of which slaps and giggles around.
@ghettoflash reporting for duty, sir!
There are certainly some drawbacks, especially because of the currently very small market, but none of the issues people seem to think are going to be big issues actually end up being so.
I think the biggest issue I here about is that gearboxes are less efficient. I imagine this has something to so with increased surface contact of the gears. I also feel like there is some seriously impressive gear tech being born in this decade in other industries. From a sales and marketing standpoint, I'm not confident the consumer is ready (if it aint broke don't fix it). From a tech standpoint, the industry would have to establish some standards to keep such a thing viable. With so many companies, and non-written standard to reference, there would be proprietary gearboxes everywhere. It would become the PC race of the 90's all over again which would leave a of companies exposed to loss.
Now with that said, from an obsolescence standpoint...and if I was a bike OEM, I would stand to make A LOT of money. The gearbox industry is massive! You could get huge players with gigantic purchasing power to develop these at a reasonable price point. I see massive potential for the industry. If I was a CEO I would start patenting tech, securing supply chain, developing standards in conjunction with the big frame developers, and allocating marketing money to convince the "if it aint broke" crowd of this tech.
Why do I bring this all up? Because to make gearboxes a thing, there needs to be a serious commitment and leadership to organize the industry. The effort needs to be super focused, more so than adding a gear to existing tech. I think you will see this happen in 5-8 years if the demand is large enough. Too much tech right now that will need to be phased out. From a financial standpoint, I couldn't release a gearbox after I released my new 1X12...I need to make my money back from the T&M effort.
All in all the worst case scenario at 250W a 1x would produce 15W or 6% friction losses.
Pinion was measured at 200W with 10% efficiency loss by german magazine Fahrrad Zukunft ausgabe 20, although I personally think the measurements were a little flawed.
Rohloff was measured by Chester Kyle and Frank Berto in magazine Human Power issue 52. at 200W with 9% efficiency loss.
Not if you use a drive shaft!
Most applications don't require such large efficiency numbers because energy is so cheap. Now imagine the human machine accounting for every % it spends, this could be a huge driver for the gearbox industry! There is no current demand for really efficient gearboxes, so there is not much investment in this pursuit. Imagine a gear geometry that is 10% more efficient in power transfer? To a mine or ship engine designer, that it CRAZY savings!!! That said it is very expensive to eak out even 1%, so the fact that it hasn't been done might mean it's impossible with current manufacturing tech.
Now this is just me speaking, but if I was a gearbox marketer looking at the 5-10 horizon, and I could pay for my R&D through another industry...scratch that...I found SOMEONE willing to pay for my next generation gearboxes...I would be all over that partnership! The Der. is a complete R&D project that the bike industry has paid for decades...it has not other application other than bikes. That is a level of investment not seen in many industries.
That is my marketers argument to SEW, or Bosch, or Bonfig, or Baldor, or GE, or (insert one of the hundreds of gearbox designers)
For this reason, I think you're going to see a separate company, like Pinion or Effigear bring this mainstream. there's just too much expenditure for an established drivetrain company to take a risk on gearboxes.
@kabanosipyvo I would honestly take that as an intermediary between current tech & gearboxes. especially with 50t cogs.
^^^beat me too it ^^^
Cars, compressors, turbines (jet, wind, hydro, whatever) for power generation... basically any large rotary equipment. A couple percentage points of efficiency in these applications can mean tens or hundreds of thousands of dollars per year in energy savings/sales. The idea of the bicycle industry leading the charge for a more efficient gearbox is kinda silly... if these other industries could get it they'd be beating down doors for it. Other industries (including mine) are light years ahead of the bicycle industry in the use of gearboxes, and yet, when efficiency is paramount you just don't use a gearbox. There's no way around the losses and the noise.
Gearbox tech has been around for hundreds of years. Nobody is about to invent a new tooth profile or lubricant that will magically make them as efficient as direct-drive, belt drive, or chain drive.
magnomatics.com
www.youtube.com/watch?v=7LOZhaxTw0I
I'm not sure if anyone has touched on the servicing of gearboxes... its another plus for the LBS. In the future I see the bike industry going the way of the car industry... there are a few big flashy sales stores and lots of garages that fix cars. The big bike companys will have flashy sales stores and the LBS will service things.
As to putting one money where ones mouth is - now we are down to two wheel sizes and geometry is settling down (I see it still changing for another 5 years albeit slower than now) I think there will be more development of gearbox bikes. The shape of the bike must be right first before you worry about how to make it go forward. I for one will be looking to buy something with a gearbox for my next bike because it makes sense.
If they are so amazing, riders would do better with them, if riders win on certain brands of bikes, those certain brands sell better... therefor the bike manufacturers would be pushing to use them. (i would think)
However, this is a market. As the market grows, business either have to match it or be willing to accept that in the differential between their growth and the market growth is space for competition to root. Think of it as a patch of dirt. If each year that patch grows at a rate that outpaces the growth of the grass, then that is increased room for weeds, or flowers, or anything else that might grow in the new dirt. If there is enough demand, and the market continues to grow...it will happen by the mechanisms that make up commerce. The UCI has pushback, but the tides of market growth are more or less non-relenting. My point, if there is enough demand...it will happen
The UCI does not always bow to reason.
After it's developed, and the magnets get even smaller and lighter - then it will be viable, even for road bikes? We'll see in a few years time, or not.
Possibilities of buyer manipulation are endless in cycling. Gearboxes are not developed because for big companies it would require submitting a big part of the design (including the part where accountant comes in with his red pen) to a currently not existing mounting standard. There is a difference between coordinating several companies for making more tyre clearance or widening the hub spacing and developing a whole new piece of super precise enginery. Derailleurs are simply easier to mount.
However as RC said in a comment somewhere here, electric motors are bringing us closer to this.
I'm not buying any of these "standards" until I know the standards will last longer than a few dozen months.
I love talking about this stuff! Very few people in my life care.
Chain Drive = 95-98% efficiency
Not bad, we've seen these numbers. Basically hard to beat, now let's look at what makes up a bike gearbox using the effigear setup for simplicity.
Assumptions;
Final chain drive = 98% max efficiency
Helical Gear = 98% max efficiency (used in the first stage of the effigear)
Spur Gear = 98% max efficiency (used in the actual shifting stage of the effigear)
Gearshafts = frictionless
Gearing Estimation;
Stage 1 = Cranks to lower gear cluster with helical (98%)
Stage 2 = Gear reduction through spur gears (98%)
Stage 3 = Output shaft to rear wheel (98%)
Stage1 * Stage 2 * Stage3 = total efficiency
.98*.98*.98 = 94% MAX efficiency
So the best possible case for this efficiency would be 94% efficient and that's with frictionless gearshafts which we all know is impossible. This makes the ~90% efficiency figure of the Pinion gearbox pretty good especially as they have a more complex configuration.
Will it ever be possible to make a gearbox as efficient as a chain drive? Maybe? But it would take some pretty crazy inventing power to increase the efficiencies of the components beyond 98%.
But is it worth the removal of the derailleur, cleaner packaging, and reduction of unsprung weight? Maybe. There are tradeoffs as with anything else. Do I want one even with the efficiency loss? You bet I do. It's sexy. And expensive. And sexy.
@ghettoflash @bkm303 @groghunter excellent discussion and points, lads.
I'm not dismissing what you're saying though, as now my argument is double speaking. However, there are some new tooth profiles that are making changes. They are very hard to make, but manufacturing tech might catch up.
If I was an aerospace engineer, I probably wouldn't waste too much time designing a super efficient system that doesn't meet my other performance criteria.
TL: DR: a bicycle gearbox actually has to withstand more torque than most motorcycle gearboxes do.
I'm now interested in the impact forces associated with backlash in automobiles.Maybe they are so robust because of the rate of acceleration? We may rival cars, but why are car transmissions hundred of pounds? To handle the reactive forces of a large mass?
To my study!!! ~flashes cape disappears in a cloud of smoke~
The Pinnion is heavy, twice the weight of Shimano's Alphine internal hub. With Shimano Steps XT e mid drive just announced how hard would it be to use that same interface for a mid drive Alphine gear box? There is your next project OneUp.
Shimano can lighten Alphine, make it stronger and add a 12th gear if they must. More sensible would be a simple internal two speed rear hub and 8 speed in the front. That would keep the relationship between crank and wheel fixed and therefore be a better system that is easier to work around.
Stop buying into this bullshit that derailleurs are the only way to shift gears on a bicycle. Its stupid. All other chain driven systems have the chain wheels in line. All other outdoor transmissions are sealed. DUH. All of the narrow wide, chain guides and clutch derailleurs are not innovations or improvements they are simply things that help force a chain driven system to work with offsets and chain angles chain driven systems were never intended to have.
There already are mount brackets to put mid drive motors on regular frames and such brackets have been used to mount Alfine hubs as gear boxes on DH bikes. It will be the aftermarket like OneUp and small independent bike companies who will lead us to gear boxes just as they did most recently with 29r and 27.5 wheels.
If the Alfine actually is much less efficient than a derailleur system at its average and maximum offset gear combos that would have been fixed by now had they put as much effort into Alfine as they have into the shit they have been selling us for the past 25 years.
Also, auto transmissions don't weigh as much as you think: an AX5, which is a light duty truck transmission, is under 100lbs(at least without fluid.)
As I said above it will be the aftermarket who starts making conversion kits to use the Alfine as a gear box that will increase demand and help push internal shifting forward to the masses. Had Shimano put the money and effort spent on Di2 into an internal shift system imagine where internal shifting would be by now. Of course the same can be said for Sram and Hammerschidt.
Its a similar deal with Sram and 1x. with its horrendous chain line and until now lack of range isn't good for consumers its good for SRAM. A 1x crank is simpler than a multi crank, takes less time to make, fewer skews to inventory, 1x instead of 1x 2x and 3x, and lets them with Eagle eliminate their front derailleur division and all the expenses that go with it.
Hey, did SRAM charge less for their 1x cranks? No, they charge more. Lower cost for them same high cost for you equals more profit for SRAM. You think Sram will pass the savings on when they eliminate derailleurs? They haven't so far so why would they now?
I am interested in the development of these technologies. Definitely a gearbox somewhere down the line could (should) be viable, but what if we come up with a chain that can bend on two axes instead of just the one? Chainline problems gone!
All the things happening in this rapidly changing industry are so exciting I'm happy we could have this 40+ comment opinion-fest.
You're right though, if you're gonna post something, please please please make sure it wasn't said already thanks
Who is still keen?
Im very keen to test one but the price would put it out of reach for most and it meant that its no longer a certainty for me. It has to be mind-blowingly amazing for me to even contemplate going ahead with it. Never say never though.
Gearbox advantages mean less energy lost from being in the right gear more often and other smaller gains. All out efficiency lost in a lab isn't a fair comparison. Caleries lost at the end of a ride is more to the point.
Profit is the only reason gearboxes aren't out. When they are by the big brands they'll be made light and perishable to support probability.
I have a gearbox bike(a few) and a mech bike. and I can tell you I would rather take the gearbox bike to conserve energy on a long or arduous ride than the bike with a mech. Mech bike is 29er, gearbox 27", would still choose the gearbox. and would expect far less chance of mechanical issues out in the middle of nowhere.
Centralized weight, being in the right gear more often, are two massive bennefits to gearboxes that can't be justified by numbers and lab tests. Ride a gearbox for a year, get fully used to it, then ride a bike with a mech and you're saying to yourself what is this primitive monstrosity of a gearchange system, bullying the chain up a group of sprockets. Mechs are a joke.
A gearbox bike could also run a shorter axle and narrower hub with the same dish and save weight there too.
The first one was a CVT. It was banned by the UCI and replaced with a cassette and derailleur in a box.
Possibly. Or truth is it wasn't terribly efficient.
ridemonkey.bikemag.com/threads/new-honda-rn01-at-keystone-bike-park.234712/page-2
The first one wasn't. It was CVT. But I don't think it was ever raced. ridemonkey.bikemag.com/threads/new-honda-rn01-at-keystone-bike-park.234712/page-2
www.youtube.com/watch?v=hakIIk7AU9o
There was a Lahar reviewed years ago by a magazine here in Oz. They put it in a group shoot out against the distributors wishes. The other bikes all beat it, the other bikes all had massive advertisments in the magazine. Basicly an infomertail.
The Lahar is still ahead of most bikes and it's what, ten years old. Press fit BB, same size BB bearings as headset, gearbox, carbon, current geo now ten years ago, and many other little great ideas. The Lahar is definitly a better bike than a Mongoose or Giant of the time, it was tested against.
And yes, you need a low hanging long derailleur, something that was only necessary for a triple.
And yes, shifting is questionable, not even close to the performance of a dual and a more compact cassette.
And yes. elephant in the room, the spacing of the SRAM cassette is silly, with 20% gap at the extremes and 10 speeds wasted to go 12 to 42.
And yes, a 50 cog will influence cinematic more than a dual.
So ... bring on a 56 and let's see where this silliness is taking us
In many situations 1 by doesn't bring more than "hey look, my cockpit is cleaner", and chain retention can be improved.
Weight gains? Yeah sometimes but more unsprung weight with heavy cassettes.
And please don't say there's less hassle with a 1by and 10-50 cassette than a 2by...
I know it's personal but as Richard Cunningham says, how many sacrifices just to drop the front derailleur ?Personally I would love a 10-36 1x10
Just waiting for the 70 tooth cassette :p
Now that means that front derailleur is nowhere close to be dead. Staggering majority of people ride double and tripple chainrings. The only question is: who stopped the time in 1995 for so many people? The answer is: some people just won't adapt. Rationality does not exist and we may as well argue about why won't Baboons wear underpants to hide that disgusting big, red arse?
I don't give a flying fk about front mechs existence. I want GEARBOX
99.999% of riders are not going to be crossing the Alps with a tent in tow so that is a ridiculous requirement to try and fulfill. XX1/XO1 took care of the large majority of riders from a gearing perspective. In fact I don't know of a single person still running a 2x setup, but I also don't circulate in the XC crowds either. Most of the riders I know are running 34T rings as well despite the fact that riding locally has a lot of elevation change. Eagle gives even more options for riders looking to make the switch. If you want to stick with old tech and run FD's have fun. More options is never a bad thing.
As someone who was shopping for an new bike, it would have cost me $4600 CAD for an almunimum Norco Sight with GX 1x11 or $5200 for the carbon version. Stumpjumper 6Fattie with GX would be $4600. Cannondale Bad Habit 1 at $4500 and the Norco Torrent 7.1 at $3400.
My wife has an entry-level Giant Talon from 2015. $600 for a 3x8, and she was balking at the price. I am sure my LBS sells many, many more of those than the Trance and the Reign.
Anyways, I decided there wasn't enough value in buying a new bike with 1 x 11. Ended up building a bike from a 2016 Carbon Sight frame purchased on here with 1 x 11 for about the cost of the entry level aluminum version. I can't imagine the average person seeing the sense in purchasing a bike for the price of one that comes with 1 x 11.
Despite what people say, 1 x 11 is still far from cheap.
:P
The supposed death of the FD goes hand in hand with the "I live only for the DH" attitude. Silly attitude when 95% of the time you spend on your $5000 rig is spent pedaling uphill.
DH is fun and I have a DH bike and do plenty of lift assist, but real AM/trail riding is still my favorite, and I love tech climbing. Having a 2x goes hand in hand with steep, sustained, tech climbs.
Just rode Moab, and I chuckle when I see the young bucks on their 1x who can't tech climb to save their lives, and are walking upper Ahab, but "live for the DH". Then turn out to be not so fast on the DH either!
Some of the best rider I know are in their 40s, who've been at it for 20 plus years, and most are still on 2x. They like crushing both the steep techy climbs and the DH - you know, trail riding.
I don't think plate sized cassette cogs with a meter of chain and a RD cage th length of a golf club is the answer.
Yeah, I honestly couldn't really give a shit about 12 speeds.
f*ck, give me 8 speeds with 10-42 cassette range and I'd be happy. Easy 4 tooth jumps between each cog and that'd be perfect.
The recurring profit from the mech system outweighs any possible starter price for a gearbox. Its about $
My bike is a compromise with 34x11-36, it's not ideal for commuting to the trail, but perfect on sweet singletracks. And why not 10-42 for those who want it.
Then choose your ring appropriately, cf @lRaphl who points out that less fit people need smaller rings, not a wider gearing.
Why 10-36 over 10-42? because 360% would be just enough for me and 420% would bring only more weight and a longer RD. To each their own, I just wanted to say that it's personal and in my case my perfect setup dosen't exist except custom cf @garcmol
@WAKIdesigns so you're saying the FD should die but some people just won't adapt?
If they stick to the FD I assume it's because it works (no dropped chains etc). On my hardtail I have 2x10, which works fine and is sweet when I cycle on the pavement to the trail.
Another example is my gf's 2x9, she's ready to adapt but it's just not worth the price (she would need 10x42, so XD driver, new RD, new shifter, new cassette, 28t ring which is impossible on a 104BCD etc).
And my drivetrains work fine so I don't understand this gearbox greed yet
I'm a hard-charging big rider, and I've been riding since the early 90's, and I have never felt in all those years that I needed a 50 tooth cog. If it's steep enough for that, it's just as fast (and probably saps less energy) to walk.
I love pinkbike's coverage of racing and the photos, but bike reviews are nearly always positive, and "opinions" like this leave a sour taste. I know RC has been around the block for a long time, but I'm starting to lose respect for the guy. Maybe he's right, but I, like so many others, are so f*cking sick of new "standards" every month, and the arms race to sell the latest thing. I'm sure it's great gear, and if someone gave it to me for free, I'd rock the hell out of it, but I can't afford to keep up with this shit, and I don't know many folks who can.
You've lost a reader.
My point is the pace of innovation is acceleration across every facet of life. Doesn't matter if it is your TV (480i/720P/1080P/4K), your car (drum brakes>disk brakes, carbs>fuel injection, airbags, navigation, crumple zones) or your home. If you can't afford or don't want the new things that is fine because nobody is holding a gun to your head and forcing you to buy. At some point you might not be able to get replacement parts, but that time is so far off that it is irrelevant. Instead embrace the fact that all of this technology will trickle down to affordable levels soon and improve even casual rider's experiences. Everyone complained about the first full suspension bikes, disk brakes and dropper posts. These are all things that are seen as basic requirements now and most can be found on department store level bikes. If 50T is unnecessary, which I think it is overkill too, then nobody will buy it. Most likely though is that 3 years from now we will all be running it and not even thinking about it.
It sucked! Could I ride the trail? Yes. Was it a pain in the rear to do it? Yes. Was I slower? Yes. Was my other bike significantly more fun? Hell yeah!
It's not about the industry pushing stuff on us, its about giving us better stuff to make mountain biking even MORE fun! Embrace it my brothers!
The pace of innovation is amazing, and no doubt some great stuff comes out of it. But I'm tired of having everything shoved down my throat like this. I don't need to buy new shit to have fun on a ride. And yeah, I actually thought triples with 11-28 were pretty good back in the day. If that's all there was available today, I'd be just as happy on it. I enjoy reading about all this new stuff and drooling over it like anyone else, but don't tell me it's better and I need to just hurry up and buy it.
To disguise it as an "opinion" is BS.
I'm sure I come off as a luddite, and in a way I am, but I am getting tired of an industry that comes up with some genuinely great ideas, and a million "innovations" that are really just new marketing and sales ideas.
I see Eagle as a way to appease the weak climbers, which is fine. But at the same time I feel we're at the point where we're discouraging developing fitness. God only knows how many squats and lunges I do to get better at pedaling.
sorry buddy - fat thumbs on a bumpy bus - you get a +1 from me
On a bike with two front chainrings:
On a full suspension bike, when you shift to the small front ring, the chain helps keep the suspension from moving, because you are pulling the chain forward BELOW the pivot point. After shifting to the big ring in front, the geometry is more linear (if designed as such).
So you can have your cake and eat it too. With a single front ring, you only have one "geometry".
As Mammal said, the book "Motorcycle and Handling Chassis Design" by Foale is one of the best resources on it. Dave Weagle has a few blog posts floating around as well.
Does somebody know?
I haven't experience an iteration of drivetrain that didn't have annoying universal issues though, and 1x solves alot of other problems.
That said it's a moot point because I have yet to hear someone adequately explain to me when a rider would really need to be able to backpedal in their lowest gear.
Though it looks like I can get away with a slightly smaller chainring so I'm going to try that and basically not use the 42. Hooray back to 10 speeds.
Very few bikes, even brand new ones, are designed with a chainline optimized for 1x. So no, I would not expect your brand new Evil to be either.
"I have yet to ^comprehend^ that someone ^has^ adequately explain^ed^ to me when a rider would really need to be able to backpedal in their lowest gear."
You're welcome btw
Also, a GB is far less likely to break. In the event that you do grenade your bb/downtube into a rock, I would personally rather have the gearbox take the hit instead of destroying my frame. Just my .02
Now, let's just take normal, x01 stuff. Say you have some on the DH bike and on your trail bike, and those are the only two bikes you ride. You get in 200 days a year, and do 5 races (meaning you ride, rain or shine, drivetrain killing mud or not). You guys don't think that, if buying brand new, you wouldn't spend $1200 in 2 full years - 400 days - of riding??
@e46s54 Refer to the above. Maybe no one you know, but almost every serious mtb rider, from xc racers to dhers, either a) deal with crappy shifting because they are broke college kids and run JensonUSA 2012 specials b) get mid end/upper mid end parts at cost or on eBay c) have well paying jobs and just pay to replace parts or d) ride single speed. When I used to race 8-20 xc races a year, and train probably 6-9 hours a week on my mtb, I would replace a chain and cassette and chainrings twice a season, and derailers probably once a season or two, assuming nothing ever broke and I didn't have to do a mud race. Last year, I witnessed at least 5 separate DH riders destroy derailers while I was riding with them.
Sorry you disagree with me, but it's no reason to call me an idiot. You wouldn't say that if you new anything about engineering or what actually goes on inside a gearbox (it's not that complicated), and you would know what I'm talking about with drivetrain wear and tear if you didn't ride like a pussy. Have a good one, pal.
You guys weren't aggressive, just skeptical. I appreciate the discussion and didn't mean to make y'all feel attacked. Another reply told me "no one" wears out stuff like that, and told me to stop posting "idiotic shit". Probably shouldn't engage in the internet dick-waving, but angry, ignorant attacks are just too easy to respond to...
As for breaking things, I think it's a combination of all things - rider skill, how the rider chooses to ride (precision vs. brute force style), and the trails the rider rides. I have been very fortunate and have not broken all that much in my pretty extensive riding history.
My suggestion to you is to not invest in overpriced tech if you go through parts like that. Stick with XT and be done with it.
My figures are based on the higher end 11 speed drivetrains (wear out 2-4 chains, 2 cassettes and 2 chainrings, and wear out or break a single derailer, in 2 seasons). To clarify, my point is really directed at the guy who is psyched on Eagle or 12 speed in general (and will presumably want to buy it), but skeptical of the GB. Also, I said $1200 in 2 seasons, which is definitely more than average, I'm aware. Regardless, the gearbox isn't even broken in until 1000km, and that's based on touring bikes, so much more continuous pedaling. With a lifespan of 60,000+ km and exponentially more durability, I just think that it doesn't end up being near as pricey as something like Eagle will be, and the average XT/SLX rider could even justify it.
Also i'm behind the times so I'm just now moving from my 30T, 11-36 setup to a 32T, 11-42 Setup. I'm really excited for some more top end speed, as I really find my 30T lacking there. I just wanna go fast!
I still think a 24/38 11-36 double is the holy grail for mtb range all you need on both ends, bit who doesn't want to run a dropper remote in place of a gear shifter? Eagle seems like a bodged way to get this range with one shifter.
Then the chainring suspension issue. Further you move from a 32 the more suspension performance is likely to suffer at least on older bikes. But running a 32 on eagle makes no Sense at all at least a 36 in my book.
This makes no sense to me...
If you don't have the fitness level to climb on a 42 cog, you definitly don't have it either to push the 10T unless you're on a paved road going downhill.
That leads me to thinking that as I write this, somewhere in Japan some 30 year old Shimano employee rushes into board room with sales prognosis for 2020. He nervously points out that SRAM can take up to 80% of Trail and Enduro market! People are dalling for the argument of simplicity, minimal weight drop and supreme chain retention! An old man in dark corner speaks slowly and calmly: So many of our clients never dropped a chain since it is hard to drop a chain on fireroad. Sram may take 80% of 20% of our market but we can take 80% of 80% of the market. "It's still a gamble Underwood San, XC racers may pick up 1x!" . Everything is a gamble mr Singlesaki - racers ride what sponsors give them to ride... it is their job for what we pay them. Our racers can win already on 36 to 42, But we give them 2x with one electronic shifter and the problem is gone... as long as there are as many racers in top20 on Di2 as there are or Eagle, the mob will be parted... confuse them and we have their souls. Tell them that road cyclists have 2 chainrings and ride 150 miles for few weeks in Tour De France, that there is a reason why there are no 1x road drivetrains. For Gods sake, let's cut that rationality bullcrap: Many Top road racers say that disc brakes are more dangerous than rim brakes!
I'd even hazard a notion, that the higher elevation change, the less usability a 1by system has, because to stretch it to appropiate range more and more tradeoffs need to be made.
First of all - longer RD cage means it is more likely to snap it off on trail features. I thought we learned this lesson years ago, but apparently we did not. Enjoy your $300 a pop "accidents". Intrestingly, with some trigger discipline one can have 2x system with more range then Eagle and SS cage mech.
Second thing - poor chainline on climbing gears, resulting in the annoying "backpedalling" issue on 1by systems. Which would not be a problem if the indistry finally got its head out of its sphincter and standarized on 150/157 mm rear hub.
Third thing - to keep weight down big cogs on our hyper-range cassettes are made of soft aluminium - this compromises durability for those who climb alot.
Fourth thing - poor chain retention on high gears. By design 1by system forces us to ride on very small cogs at the back, where there is least chain tension and cage position on the RD makes the clitch nigh ineffective. yet most people choose to ride with no chain retention device - begging for an accident to happen as wear goes up.
Fifth thing - weight. Eagle XX1 cassette is approx 1/3 heavier then XX1. Sure, X-dome cassettes are light, but pleb tier GX, NX or shimano cassettes with such spread would weight a lot. If we extrapolate the XT level 11 speed 11-42 to eagle level, then it would come at 550g. I shudder to think how much deore level cassette would weigh.
Sixth thing - roller coaster riding. Most of my friends who switched to 1by now also ride 26/28T front rings. essentially riding on their granny gears all the time and being bereft of one of factor of control over a bike.
Most importantly tho - I am all for choice, ride whatever you want. However, my new bike, which has an unique geometry feature I want, was designed around 1x system with maximum ring of 32T. Thus forcing me to use 1x. Getting an FD on that bike is going to be a major hurdle, because the designer was lazy and followed the fashion, taking a crucial option away. At this point my only option for front shifing would be to procur Hammershmidt crank.
Honestly, how does adding 4 more huge cogs in the rear with no room left in between for a chain make more sense than a 8x2 or 9x2 gearing system? It is heavier, in the wrong place as well, an extra long cage is needed, as well as an extra thin chain. It makes absolutely zero sense to me.
By saying "This really does sum it up", I'm trying to get across that TimRidesBikes said what you just said in one word.
In other words, I agree with you that it makes absolutely zero sense!
Once more, I understood the point made by TimRidesBikes, I just thought I could rub a bit of salt in the wound.
From my experience, although not vast, I think I would take an extra pound in the bb and keep the unsprung mass down, center of gravity low, etc.
There was a time when I would check my uphill splits, but I would wager that by and large, MOST mountain bikers do not give a flying shit if they are 20 seconds faster on a 15 minute climb or not, but would appreciate all of the benefits of what you have mentioned.
Oh, and you forgot unsprung mass and a wider flanged hub, which are both huge benefits, IMO.
My bike probably weighs 32-34lbs, havent weighed it yet. It doesn't have a single piece of carbon on it. If I really want it to be lighter, there's so much I could change before really complaining about the weight of the gearbox.
I urge everyone to ride one. I have been yelling about their superiority from an engineering perspective since I saw a Zerode. I never had a chance to ride one, but then had the opportunity to put my money where my mouth is, and I'm happy I did. Plus, if you aren't racing and strava isn't your lifeblood, you really have nothing to lose by running a GB.
So much fretting about a pound, you'd think no one would ever ride with a kilogram of water strapped on their downtube. Which, from my experience has virtually no effect on handling in more typical everyday real-world situations. Pound or two in the rims & tires, no thanks, but a pound in the low-point on a frame, who cares?
www.bikeradar.com/gear/article/22-inspirational-cycling-quotes-34881
Most of the time i'm pushing 34 up front, the 21 for the GoodSirmartin type climbs.
All this 1x is just $ fixing a problem that did not exist. I ride a gt distortion with idrive which has zero chain growth dues to eccentric design of bb. My suspension is always active= sweet
Also, hearing rumours that there are problems back pedalling when in the biggest cog on the rear? Yes/No? Not sure why vs 11 speed - isn't the chain narrower and cassette same width?
In the bike companies defense, though, they stopped making rear ends wider at 135/142 for so long because any wider starts affecting things like q factor, especially when trying to accommodate triples.
Wolftooth does a good job of explaining why boost chainline is specific to what bike it on, & that if you have enough clearance, you should actually run normal rings even on a boost bike, because it gives you a better chainline: www.wolftoothcomponents.com/pages/boost-chainline-and-chainrings
I didn't experience any of this backpedal derailing stuff with 10spd/142 but I am on an 11spd/Boost.
at same time, I'm interested, because it would allow smaller cassettes with the same gear ratios, & should improve chain retention.
That said, a couple of questions.
1) Do people really need 12 speeds?
What's wrong with spreading that range across ten speeds?
2) Do people really need a 50 tooth gear?
Might a cheaper alternative be a 94 BCD setup with a 28 tooth and a 9-42 (1x10) or 9-44 (1x11)?
E*13 TRS 1x10 -> 9-10-12-14-17-20-24-28-35-42
I'd imagine that those last two 7 tooth steeps may seem a bit much.
Of course, the gaps aren't as big on the 1x11.
E*13 TRS 1x11 -> 9-10-12-14-17-20-24-28-32-38-44
That said, I don't feel they are problematic, but that's a matter of opinion of course. For me, I like the idea of a 9 tooth cog on the bottom. Since my frame seems to work best with a 32 tooth up front, I'd like to regain some top speed I lost when I went from a different frame with a 36 up front.
I see deals on SRAM group sets, but since I'm happy with 1x10 AND I want the 9 tooth cog, the E*13 feels like the better idea for me personally.
Besides, without the markdowns I'm still seeing at least $450 for a 1x11 SRAM setup.
Let me ask you this: have you actually tried a 32x10? Do you really know that it's not enough? I'd go the new drivetrain route, & if, in a few months, you feel like it isn't enough, sell the SRAM cassette & but the 11 speed ethirteen. I'll add this: so far, GX shifts better than either of my 10 speed drivetrains.
@groghunter I feel the need to say that I hope I don't come off too snobish; really any modern drivechain choice is light years better than what was around ten years ago, and the gaps in shifting really is just a nuance. That being said, however, since there are so many good choices out now why settle for one that doesn't fit what you want exactly?
Then changed frames and started running a 32 tooth up front. There was a gain, but there was a loss.
Why would I want more top end now? Because in a number of races I've run (Super D's in particular) I've found myself feeling like I've spun out. The TRS would give me 2 teeth back in top gear!
Hard to pedal? Hit the gym!
50 tooth granny for going up
10 tooth to wheelie out of berms
Any trail I've ridden when you even approach that speed you are either pumping or braking
-oops I realize i repeated myself, but....
s-media-cache-ak0.pinimg.com/736x/c6/92/34/c69234deca28eb1bc4d8335f2101333c.jpg
That said, it's not really a problem - a quarter or half turn backwards on the cranks (enough to position them to get over tricky features while climbing) will be fine, because when you pedal forward again, things on the bottom of the cog haven't changed over yet. Might lead to more wear - but hasn't led to problems. And really, how much backpedaling do you do when in your bailout climbing gear?
I suspect that normal chainrings allow the chain to start angling/curving over to the cassette cog while it's still on the chainring, because they're so thin. Narrow wide chainrings are so much fatter and fit the chain EXACTLY, so it has less space to angle over to the cog. Would be especially bad with short chainstays and/or 26.
plain simple.
Example where low ratio is needed:
www.strava.com/segments/690729
Combine that with 3 liters of water, picnic lunch, etc. And that is a gravel climb, ride up the trail instead and it is physically tougher (but less soul destroying.)
I'd really like to see weight/price analysis of Eagle. I'm personally still stressed about the cassette cost, usually my shimano xt last 1-2 years which is ok for $50. XDome 12 has msrp of $420. How long will it last? How much does it weigh? At some point the weight of front shifter, derailleur, cable, inner ring and bolts will be less than the weight of those huge rear cassette cogs.
Then again, I'm a happy sram x0 2x10 user. Never had a problem with the inferior front mech, its terrific compared to the old days.
Would electronic suspension obviate your second concern here about suspension kinematics?
Is there a trend to adapt things to the don't so prepared in mountain bike?
but like I said, I don't know much about suspension.
Compare a proper short cage 9sp rear mech with any 11sp or 12sp mountainbike rear mech. These modern cages are more like long cages of back in the day really! Those claiming that those one-by drivetrains allow you to run a shorter cage than a two by drivetrain are too much stuck up in their math and too little in reality. Run a short cage rear mech with a two-by drivetrain and make sure that the chain is long enough. That is, make sure that the chain is long enough to accidentally be shifted large-large and, if you have rear suspension, you can go through the full suspension stroke like that. Yes if you accidentally shift small-small the chain may go slack, so what? You'll notice, you'll shift back to the regular ring and you'll be fine. So basically you'll just need a cage that has enough capacity for a single cassette. If you run a bigger cassette (for a one-by drivetrain) you'll need a bigger cage. That's pretty much my main reason to not run a one-by drivetrain, I don't want the hideous long rear mech that goes with it.
The whole suspension kinematics advantage is lost there as the advantage simply isn't there. Run a two-by drivetrain and frame designers should just design to make it work well for the regular ring. Just as RC points out with the extreme angle the chain runs at when in the lightest gear, shifting to the granny gear won't give you perfect suspension setup. And if that is no problem for a one-by system, it is no problem for a two-by system either. And even for the front ring, some riders prefer a 38t in the front (so they can go faster), others prefer 32t for that same rear cog (so they can climb steeper). Suspension frame designers still have that uncertainty to work with. The white frame pictured there, does it actually have the wheel axle on the bottom link so that the axle actually rotates around the pivot shown there? If it doesn't (if it is some FSR type design, for instance) the picture shows nothing at all in this context. If it does, the picture shows us that the whole statement doesn't make sense at all. The chain is clearly way above the pivot, Bob Girvin would be so sad!
So what do we have, we're saving ourselves some sprung mass (granny ring, front shifter, cable and the difference between a front mech and a top guide) and in return we're gaining some unsprung mass (bigger rear mech, bigger cassette and a longer chain).
The only advantage I currently see in favour of the one-by setup is the amount of rear tyre clearance. But really, a 22t front ring doesn't take much room. With the introduction of the SLX group (I think it was then), the cage of the front mech got smaller as it doesn't necessarily have to work with a big 44t ring anymore.
If SRAM and Shimano modify their Spectro respectively Nexus rear hubs so that they can be used inside the frame of a mountainbike, I'm pretty sure you should eventually be able to get a 7sp or 8sp mountainbike with an internal gearbox for maybe 200 or 300 euro more than a sensibly equipped SLX (one-by if you will) comparable bike. I can see some advantages there for mid-level mountainbikes.
Enjoy!
@davemud Yeah I think GT had a prototype as well. Actually before I heard of Pinion, Nicolai used to build a Rohloff hub into their frames to turn it into an internal gearbox. I still believe Alfine or even Nexus could make a fine poor man's solution. They'll have to make minor modifications to make it work as a gearbox anyway. But once it is in the frame (and they sealed it properly) conditions are actually better than they would be if the hub was actually being used as an actual rearhub in a commuter bike. As I read elsewhere here (in a post longer than mine) the lower end versions of the 1x12 derailleur system is going to add obscene amounts of unsprung mass, most notably in the cassette. So lower end gear hubs like Nexus could actually provide a viable alternative.
You are right about 3 speeds and 7 speeds being simpler and some braniac with a machine shop is finally going to figure out putting the 7 speed in front and the simpler, lighter 2 or 3 speed in the rear hub. to get that full range back with a fixed chain line and the heavier piece in the middle at the bottom of the frame where a bit of weight might actually be useful.
Most important is for consumers to realize we never needed to get all of our gears from one end of the drive train. Convincing north americans this was better allowed Sram to first make simpler cranks and charge more for them to make more profit. Now with the release of Eagle they have said they are downsizing their operations by eliminating their front derailleur division. Doing so will save Sram money but they won't be passing those savings on to the consumer so again more profit for them.
Don't fall for it people.
Who said we ignore wheel sizes and have accepted boost?
What if we could have an e-motor that mimics the leg-input intensity you experience when switching gears, but still gives the power output at the rear wheel? Not a throttle, but essentially an electronic shifter that still increases the leg work you need to input like a real bike, but transmits that increased leg input into electronic power. A genuine compromise, in theory anyway, to remove rear mechs once and for all.... Anyone know if it could work and make pro and anti-ebikes both happy??
Also I just don't need 12 gears, 8-10 gears on a 40-11 on 34 narrow/wide is fine for me. Seems the are just making cool innovations but really they just aren't necessary.
i believe this is the sweet spot between high and low ratios! ! after this i think everyone can take a chill pill and stop R&D on gears.... i wouldnt mind seeing a third or fourth player in the drivetrain field... (derailleurs and shifters)
"Almost" seems to be a hasty generalization considering the number of mediocre bikes in the 150-170mm travel category (*cough*Jamis*cough*).
The size of the front ring does not matter as long as it stays constant.
the number of inches travelled per pedal stroke (gear inches) = wheel dia x (teeth front cog/ teeth rear cog)
As an example for a 30 tooth front and a 100 inch dia wheel you would travel:
10 tooth - 300 inches
50 tooth - 60 inches
Hence you travel five times as far in you big gear - or a 500% spread (300/60 = 5 or 500%)
I have seen some really good riders out there that use single speed rear hubs and cram 5 gears in the small freehub body.
On 29ers ! Impressive!
Multi day expeditions in Nepal I can see the point,but for weekend warriors doing 15mile,I don't.
Like 70km and 2.300m impossible to use 32/36
But I strongly disagree with you : people are different and I know people who ride twice a week (they're fit) and prefer 22-32x11-32
In live on the north shore vancouver , two weeks ago I did 550m in 10K . 2x systems are still the bomb. I still see more 2x then 1x here.
Simply put if you spin too big a gear, you're going to blow out your knees. Same reason people do not drive everywhere is 5th gear: because your tranny (and other engine parts) would implode.
@jase111171 Taking the easy option of lower gearing is necessary for a lot of riders. A lot of my friends simply can't ride at the weekends due to family commitments, meaning they are relegated to an hour or two after work once or, if they are lucky, twice a week. Just "getting fitting" isn't really an option. Are you so elitist that you feel like they shouldn't be catered for as they aren't serious enough?
I realize that everyone has choices in life and bikes aren't at the top of people's lists. However, I am sick and tired of the trend of "oh look at my lazy, first-world ass that needs to be catered to because life is so hard" attitude coming over to mtb. Everyone needs to quit their bitchin. You can find time to do squats, jump rope, ride a trainer or whatever for an hour a day or less. Thing is, most people refuse to put work into get in shape. I know I am certainly not the best (pretty bad about consistency, actually), but I am under no illusion of thinking it's because I just don't have time.
I'm not saying their should only be options for the super-fit; in fact, the mtb industry already caters towards the middle of the road rider (look at how shocks, gears, etc come pre-set -- for pansies). I am merely pointing out that there's way too much of this, "Well I can't be in shape because I have real life to take care of" attitude, and it's simply not the case. People just get lazier and lazier; no one said it is easy to not be a fatass, especially when we live in a world of increasing laziness, gluttony and sedentariness.
TL;DR: if you're out of shape, quit yer bitchin and train. Why train? To get fast (and be healthy, ya lards!). Why get fast? To have more fun, for longer.
I've got no time read a ignorant post from 22yr old that lives in flatland with no mortgage,dependents or responsibilities. Come ride the shore when your almost 50 having had lots of sports related injuries over the years and see how you do.
I jest - long live innovation!
So in addition to the longest chain and rear derailleur cage ever seen on an OEM mountain bike drive train it is also working backwards and sideways from one of the original benefits of 1x .It puts a cog on the back wheel that is larger than the largest ring of any mountain bike triple crank and offsetting it one more step.
What new hub, BB and frame standards will they add next year to try and make it work in the real world of mass production and normal wear and tear?
Has anything change in mathematics since I have finish my school?
50 is 5 times 10 (=500%)
10 out of 50 = 20%
20%*10/50=4%
wtf am I even doing here
Illuminati Confirmed
@daweil don't smoke reefer and get on PB. It inevitably leads to these situations
I don't understand all the commotion around 1x10, 1x11, 1x12.... Is this a weight saving thing?!
50t back and 34t front? who the hell needs this? If you can't pedal with a 34t in the back, something is wrong with you!
I still run a 3x9. 42t-32t-24t up front (don't remember the last time I used the 24t chainring) and a 11-32 in the back. I don´t remember dropping a chain either...
My last ride was a 37k with a total climbing of 1368m, with places having 21% grade, never needed anything fancier than the old X9 I have....
www.pinkbike.com/u/biggerted/blog/Sometimes-ten-is-just-one-too-many.html