Bike Check: Brett Tippie's Glow-in-the Dark YT Capra 27 - Crankworx Innsbruck 2018

 And generates magnetic field

 @WAKIdesigns: positive magnetic field

 @amirazemi: a magnetic field can be neither positive nor negative, but is directional. Charged particles moving through the field though...

Try translating positive and negative charges to an alien civilization

 @allballz: that was tits.

 @allballz: haha never thought my physics phd will come in handy on pb

 @allballz: I knew SOME people who ride bikes are smrt.

 @allballz: you mean that suspension compression could be used to propell the bike?

 All the critics gave it glowing reviews.

 it brightened my day

 More light hearted bike checks please...sigh

 Brilliant

 This new paint makes the bike a lot lighter. The difference is day and night.

 I met him racing. He's a really nice guy and really helpful

 100% agree. I was in Vancouver for work and only had a day to ride and had some brake problems. Stopped into the hub and he had them fixed in 20 mins! Other shops would have had to keep my bike for a few days. Top notch service.

 Dave is the best!

 how do you find the 170's on the steep climbs?

 I did the same thing this year. Loving the 170mm for all terrain. I live in a flat area that is rooty and constant up an down. Not much flow anywhere.

 @rrolly: Just don't make the switch if you race cross country....I thought it wouldn't be noticable, and it's not really if you're just trail riding or doing park laps, but after 45 minutes of fast climbing and watching other racers slowly creep off into the sunset... i've been wishing I had my 175's back... also depends on how tall you are I guess, but I did notice a difference.

 @rrolly: My local trail area is an old phosphate mine turned into a bike park in the swamp. Its lots of fast steep climbs with short steep fast downs. Lots of rocks and roots. My last bike was a 17' Tallboy with 175 cranks. There was no getting around pedal strikes. You could tailor your riding a bit, but no getting around low bike with long cranks. So god dam annoying. Got a 19' Stumpy 29, came with 170 cranks....changed everything. No strikes on climbs, railing berms, or going over roots. Pedals still look new. IMO, big difference, for the better. I promise you will see more and more bikes in S/M coming stock with 170 cranks.

 Anyone of average stature use 165mm on a trail bike?

 @acali: I'm using 165s on my Enduro bike. My /gf says I'm 5'8"

 @gonecoastal:

5" and wishes you were 8

 @acali: I found 165 hard to pedal on trail bike, it's ok dh but when you need leverage I can't find any, maybe I'm just weak... Also I'm short 166 cm

 m.pinkbike.com/photo/10164903

I don't remember, which parts/decals were glowing ?

 I think it was more recent than that.

 It's not short.. it's just far away.

 @Dropthedebt: at least that’s what you tell the mrs!

 No hallucinagan's were used in the construction of this bike.

 I had the privilege of demoing a 29 Capra, its effin awesome! I’m 6’1” and L was perfect for me. I tried an XL also and found it a bit too long. If you dig longer reach go L, if u want something more comfortable to ride for longer durations go M.
Bike is a beast. Loved it. Climbed better than I’d have ever given it credit for and descended as well as my DH rig.

 Crank length is mainly about biomechanics of power delivery depending on your body physiology (body part size, muscle fiber composure) and desired effect (long steady climbs vs steep technical stuff requiring trial moves), whereas rock strikes are 99% down to rider skill and ability to generate momentary power with ratcheting and costing over obstacles. Sure certain bijes may have a too low BB but it still should not be any bigger case. Sutting and spinning through rocks and roots is not the wat ro go. I highly recommend looking into Ryan Leech balance course.

 @WAKIdesigns: I guess that explains why all dh bikes/riders use 165mm cranks ????

 @JRW82: erm, I was speaking of climbing and when it comes to DH bikes it's not only about pedal strikes it's also about hip drive which is extremely important for descending, go ride pumptrack with 175 vs 165 cranks and you'll see what I am talking about. 165 cranks make it easier to pump and corner. 175 cranks are good for punching steep technical climbs because for most folks they give you more power from each pedal stroke due to increase leverage. Compromise. Choose yours. Experiment for prolongued period of time.

 @WAKIdesigns: Crank Length
When I present on the topic of crank length, I begin by asking where crank length came from. Where did these lengths that we consider “standard” originate from? There are some theories dating back to the origin of the first push bike, or the length that was optimal for the penny farthing bike (bike with a large front wheel and small rear wheel). Most likely, crank length has just been passed down from one generation to another and over time has just become accepted even though there is no basis for the current “standard” with the current bicycles we ride today.

There has been a lot of great research lead by Jim Martin and John McDaniel on the topic of crank length. During the initial study, Martin1 looked at max power and found there was no difference between 145 to 195mm crank lengths, he did note that there was less oxygen (O2) uptake with the shorter cranks.

In the next step, McDaniel et al.2 looked at efficiency and setup a study where cyclists used crank lengths of 145, 170, 195mm, where cyclists pedaled at 40, 60, 80, and 100rpm, at an intensity of 30, 60, and 90 percent of blood lactate. The results showed that O2 uptake increases as pedal rate increases. It’s important to note that pedal rate is not cadence and is defined as the speed of the pedal along it’s axis.

An easier way to think of this would be would be if you took two athletes and placed them on the track. One in the inside lane (we can call this the 145mm crank) and one in the outside lane (the 195mm crank) and both athletes had to run 1 lap (revolution) in 1 minute 30 seconds. The athlete in the outside lane has a greater distance to cover and would have to run at a faster rate than the athlete in the inside lane to both complete one revolution of the track. This would be the same as an athlete pedaling a 145mm and 195mm crank at 90rpm. With the 195mm crank length, the foot speed is higher to cover the revolution at 90rpm compared to the 145mm crank length.

Most report that when they switch to a shorter crank, that their cadence increases. It is theorized that the increase in cadence when moving to a shorter crank length isn’t due to trying to make up for the lack of leverage, but to replicate the foot rate/speed an athlete is accustomed to on a longer crank and to use the extra available O2, which is minimal.

Leverage is another factor to consider. Crank length is only one lever in a series of levers on your bike (wheels, front chainring, and rear cassette). We can change both the front and rear cassette on the fly by shifting gears. Looking at the lever system this way demonstrates how small changes in crank length has minimal impact on the available leverage in this system.

 @titaniumtit: www.active.com/cycling/articles/crank-length-does-size-matter

TL R: 170 or 175 makes no difference (0.5%) of max power, and shorter cranks give you faster power delivery. So if you are hitting rocks, go for shorter cranks. The leverage of longer cranks can be achieved by changing gears (interesting that pedal speed is INCREASED with longer cranks).

By the way, I know I've only put one URL up there, but it is the best in the amount of time I cared to spend looking because I know after reading many articles/studies on crank length you won't find an article that says that 5mm change in crank length vastly affects power or endurance or anything you care about. But it does affect rock striking.

Personally, I just run what came with the bike and put crank boots on. And then I go ride.

 @JRW82: once you get to a steep rocky climb you can toss all that research into the garbage because it has nothing to do with efficiency, it has to do with making it through the section and to the top. Longer cranks allow for more modulation of power and more low cadence power, giving you a tiny edge for a harder gear. Regardless of that it is hard to argue whether 170 are that much detrimental, what is absolutely certain is that pedal strikes come mainly from lack of skill. Even on downhills no good rider will risk pedalling in spots where he can assume (basing on experience) he may clip a pedal. Argument of going for shorter crank length to avoid pedal strikes is fundamentally flawed. As for the rest of things we do with our cranks you can explore that and it makes lots of sense. Find your compromise

 @WAKIdesigns:
I would tend to agree with this statement going on my experience and knowledge but not being a complete tech head I wouldn't know for sure.

 @JRW82: correct.

 @iamamodel: correct

 Better off going 165MM, will feel a bit strange at first, but give it time & will see benefits, funny how most have not even tried shorter cranks unless cant ride rockier trails?

 @WAKIdesigns: Cranks are personal preference, I cant stand 165mm, feels restricted when pedalling, or 175mm, so much movement in the legs and doesnt help with going forward . 170 feels about right and is what most bikes have now anyway (im 6’3’’)

 @zyoungson: agreed. And most of the math goes out the door when you use flats or have poorly adjusted clickies and or cleats. And like the other chap pointed out, cranks are only the first of many factors in this equation. I personally try different lengths on each frame. Bb height. Use case. Wheel size. Gear ratios. Frame geometries. Poor habits die hard. Previous injuries. Just look at what Fabien Barel has to ride due to one leg being severely damaged. Extreme example. One cannot simply state there is a definite equation. Each individual will be a unique use case.

 Everyone is also missing one important thing. Stability. The taller you are the longer you ideally want your cranks. Similar to a snowboard or even bike handkebars. The more narrow your stance the less stability and control to a point. That's why even on dh bikes companies usually spec longer cranks on larger models. Depends on where and what you are riding as well. I've found I can get up steeper tech climbs easier with a shorter crank because you can control speed easier. Much easier to apply power when you need less torque to increase your speed on short punchy multi move technical sections.

 @makripper: Yes true. I find it easier to shift my weight around the bike with slightly longer cranks, as this gives me a wider range of movement. I'm 6 ft, and I find short cranks a little constricting.

 @JRW82: good info. Interesting re: higher O2 uptake at higher pedal rate. I’ve long been a proponent of shorter cranks, mainly for leverage and biomechanic reasons. This study seems to bear that out. I would add to also consider the lever lengths of the rider, mainly foot and femur, in order to create the combination of the strongest and safest position (for the knee joint) from which to pedal. My background (which is strictly spacial biomechanics, not biking specific at all mind you) tells me this is pretty close to 90 degrees at the knee when the crank leverage is highest (180 degrees).

 @WAKIdesigns: Why are you trying to sound like an authority, uses phrases like biomechanics, muscle fiber composure, power output etc.? Because you took a Ryan Leech course? And someone posts a study that appears legit enough and you write it off and tell the guy “Compromise. Choose yours etc etc.” Stay in your lane dude. Stick to trolling and your unintelligible over-educated-yet-entirely-ignorant ramblings.

 @WAKIdesigns: lack of skill my arse waki you talk like your a pro and I've probably been riding far longer at far high a level than you have. Go race an rock infested ews and when your trying to maintain speed by pedalling on the rough any rider of any level will be getting a crank/rock strike here and there. Bang your long cranks on for xc but for dh it's 165 for a reason and that's clearance not because got nothing to do with skill you mupet. As with all things enduro give it another few years and 165mm cranks will be widely available in 73mm bb's for this reason. As it stands the majority would go 170 as this it's typically the shortest that's available

 @makripper: mx bikes have got pegs in line. No issues with balance here....

 @makripper: thats a great point. Also why crank brothers mallet dh offers a 5mm increased q angle, for a wider base = more stability laterally in the transverse plane...

 @JRW82: truth. thats why there is massive amounts of testing for pro road riders to find the right crank length, chainring profile etc. It's about power and efficiency with not many variables. With mountian bikes there are way more variables to consider. you can try do the same thing with mountain bikes but the results of the tests will just be frustrating. You will find to maximize power and efficiency you will need a 182 (just a stupid example) crank length and x chain ring at x cadence at x rpm at x pitch. Good luck making that work in the real world of mtb with rocks, bumps, off camber tight corners, g-outs for suspension, etc.

 5mm is an amazing difference for pedal strikes. I always thought it wouldn't make a difference, but I have the experience now to say otherwise.

 @dtm1: also those narrow cb mallets can cause issues un clipping with wider dh/ enduro shoes. Ok with narrow xc type shoes. CB Changed an old pair I had to wider axles for free and problem solved

 @WAKIdesigns: LULZ dude. Every word of this is bassackwards wrong. This is where you hide behind your tired schtik of acting like you’re trolling right? Act like you’re an authority, tell everyone how the world works, get called out because you’re flat talking out of your arse, and switch gears acting like you’re trolling. You’re the classic example of the kid who runs in front of a parade with his little baton and yells back “keep moving boys”. You talk of ego, id, equality, parity, reletivism, socialism, blah blah and yet you have the biggest ego on here, combined with an astounding degree of ignorance. You have to be right at any cost. Boring

 @dtm1: oh thank you for telling me what I am doing here. I wouldn't know.

 @JRW82: completely different kinematics. different power. MX bikes are much more different in lots of different ways. You almost ride them similar to skiing in some ways and the moto does way more work than a bicycle.

 @WAKIdesigns: “oh thank you for telling me what I am doing here. I wouldn't know.”

You’re welcome. My bill is in the mail.

 @dtm1: I have sent it to my sponsor with a note:

Said that pedal strikes are often a result of bad stroke timing - unthinkably unlikely. Got a reply involving EWS racing references and a few scientific studies on importance of chosing proper crank length.
Yours sincerely Waki

Reply:
Dear Waki, I have reviewd the invoice you have sent me. You idiot. You can criticize someone's crank length and say that engineers at X company are pieces of shit that Pinkbike editors are advertiser sucking whores. Never criticize someone's skill. I'll get it off your salary for June.

Kind regards, Satan

 @WAKIdesigns: satan wouldn't sponsor you. you're more the purgatory type. forever floating around in limbo.

 @makripper: Purgatory has been shut down a few years ago, Jesus is cutting the costs. I am currently providing "Mohammed fells of a bike" paintings for Satans new hotel.

 @JRW82: most World Cup riders don’t actually run 165’s because it handicaps power.
They just learn where they can pedal and where they can’t.

 @iamamodel:
You’ve used some weird statistics to show a small part of the whole equation.
In a situation like mountain biking where you’re constantly putting down power that if you didn’t you’d stop dead due to very little momentum.
These test you’re quoting don’t represent that at all.

 @WAKIdesigns: it doesn't matter if it's shut down, you are still in there. it's like an abandoned blockbuster. you are still roaming around looking for the new releases.

 @dtm1: It's not delusion, it's the 'absolute certainty' of ironic meta-trolling. Due to lack of skill, Sam Hill must use 165mm crankarm. Long live the cults of personality.

 @JRW82: next beer on me.

 @jflb: none of us are Worldcup riders. You speak of less than 1% of dh riders.

 @jflb: fitwerx.com/mountain-bike-crank-length-likely-long

Doesn't handicap power. The opposite in a way.

Who rides longer than 165 for dh then?

 @JRW82: you have no understanding of power generation what so ever, you just read articles without being able to understand the context. So doesn't the author of this article who cannot tell fireroad racing from riding on a singletrack. Come back to me when you get a glimpse of understanding of power coming from low RPM and high RPM as well as influence of crank length on hip drive, not to mention generating power from hip drive. Can you even tell the difference between strength and power? a 4x4 drivetrain VS Formula 1 drivetrain? I haven't said ANYWHERE that short cranks are bad, but as expected some of you immediately try to play the "Team" game, in this case: team short cranks VS team long cranks. All that by the occasion of talking about rock strikes, just trying to fit your two cents about a few articles you just read. Wll I read tens if not hundreds, many of them not based on roadie science. I will tell you more, if you read more of people like this lost sheep you posted, you will hear that seated pedaling is more efficient. good luck learning ANYTHING by sitting on your bum on climbs. That is exactly the dogma that prick is writing about, and it makes people hit pedals on rocks. If you can't ratchet, pump, gain momentum before a set of obstacles, carrying speed through them, then 120 cranks won't help you. Good luck living your life by "it's not my fault" Unbelievable.

 @WAKIdesigns:? "Come back to me when you get a glimpse of understanding of power coming from low RPM and high RPM as well as influence of crank length on hip drive, not to mention generating power from hip drive. Can you even tell the difference between strength and power? a 4x4 drivetrain VS Formula 1 drivetrain? " if you insult then substantiate! Can you? I have my proven doubts. But please explain without insulting!

 @WAKIdesigns: i dont think you understand hip drive at all. It has to do with firing of your glutes and proper rotation/positioning. you can achieve this from a seated position if your seat height is setup correctly. I play with this all the time as prime position is always changing for me. lately it's been about 15mm higher due to me training my legs for more extension and hip rotation. i'll lower it about 5mm soon and i'll leave it for the summer unless my training changes or something in life changes.

 @Keit: hip drive has more to do with squatting than actual biking.... it is the idea of powering your glute/hip region to do more work. it's a minor part of the xc biking world. more to do with powering and pumping while standing DH type situations.

 @makripper: deadlifting more than squatting. i am done here. It's not their fault they hit rocks with pedals, it's too long cranks. If you lived where I live, with that attitude you'd quit MTB in less than a year. So Good luck. Oh I hope you aren't using crank boots on carbon crank arms because compared to an alu crank like Shimano, you have like 5mm longer crank due to more material around the pedal. Fk me...

 @makripper: thank you. Is it also so, that if you are able to apply hip power while seated the bike is not adjusted according to your anatomy?

 @Keit: exactly. there are people who specialize in optimal position for you and your type of riding. I get it done once in a while and then write down the results. its very helpful!

 @makripper: let me get the next virtual round.

 @WAKIdesigns: I always use aluminum cranks. I like a bit of crank flex when cornering. it makes me feel like im doing it right haha. Yes deadlifting. my bad. I had deadlifting in my head but it got lost in the diarhea. some people don't have rocks in their riding areas and don't fully understand the dynamics of riding with them as obstacles. The sheep become the wolves.

 @jflb: I agree. The variability and dynamic nature of MTB is why we love the sport, but it also makes it harder for boffins to study in a lab. My goal was to address the OP's concerns. If he is hitting rocks, going from 175 to 170 or 165 will be far more beneficial than detrimental.

 @iamamodel: who said it can be detrimental? I just said that paying attention to timing of pedal strokes will be FAR more beneficial. You don't need a study for that. Students at RLC learn that in a matter of few weeks of practice. Even I who don't ride can do that. If you go to an average enduro race and see a flattish rough section you'll see all clipped in Joeys mashing pedals and redding out their vision, ramming into every single rock or root, looking like they are choking on a dick. If you see any above average dude you'll see how he pumps and gets most of each pedal stroke, trying to stay on top of things. So how about that: flat pedals are better for avoiding rock strikes if you are a beginner, because they force you to be smooth - who's in for a story about efficiency of clipless pedals? Because it seems I just made an argument that flats are better isn't it? And BTW, I ride clipped in on 170 cranks on my bike now, and have been hitting rocks extremely rarely on 175, even on a HT with super low BB...

This discussion is like this Sintra dude on Pole, who said that if you have problem with handling the bike when climbing through a steep rock garden, the solution is not to lift your arse off the saddle, move your COM further up front, no... it's to sell your mainstream bike an buy a Pole because it's geometry solves that problem, you can keep sitting and spinning 90-110RPM on giant saucer of a chainring. And then you have the other dude who told me that long bike suck for switchbacks and that rocking and hopping is an excuse for poor geo. Also, how about we put a smaller chainring on to avoid it hitting rocks - there is research about higher cadence and shit - I'm sure many Pinkbikers could make a case that we all run too big chainrings just like we run too big cranks.

People will go to incredible extents to just keep on sitting on their arse.

 He obviously hates pedal strikes..

 Might only be 165mm but they are a fucking sweet crankset

 @Hammer48: Not the only one haha, doesn't the shorter the crank arm mean spinning faster?
#GENUINEQUESTION

 @titaniumtit:

I dunno..I spin 175mm cranks faster than other sizes. I think it depends on your shoe size, and possibly your build, i.e. long legs vs shorter legs and the make up of your leg muscles.

 @titaniumtit: With the same gearing and wheelsize he'd still pedal the same rpm for the same speed. Velocity of the feet is slightly slower, force applied slightly higher. I run 165mm cranks on my mountainbike too and if something shorter were available, I might try that too. My unicycle cranks are much shorter even, no downsides.

 @titaniumtit: Your feet move a little slower, because your foot travles a shorter distance while it's moving the axle by the same amount compared to a 175mm crank.

 @vinay: thanks for feedback/info, will bear both your's and Sadem's comments about shorter crank arms in mind when choosing.
:-)

 @titaniumtit: So Tippie's legs must pack quiet a punch :-)

 @Hammer48: shhh, waki may hear you. There'll be no end.

 I hear ya! Just recovering from a broken toe and resultant torn shoulder from a recent pedal strike at high speed when borrowing a friends bike, I put 30mm longer atc forks on my steed and that has made a massive improvement