Is Crank Length Important To Professional Cyclists?
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- Äas pĆidĂĄn 23. 02. 2017
- Do pro cyclists crank lengths match up with their body height according to Matt's formula? Matt investigates
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Ex-Professional Cyclist Matt Stephens investigates if the crank lengths being used in the professional peloton are relative to body height.
Matt talks in depth with Adam Hansen (Mr Grand Tour) of Lotto Soudal, who is a finisher of 16 consecutive grand tours. Adam uses 180mm cranks, and justifies his decision.
We would love to know your thoughts on the Crank Debate in the comments below đ
Watch more on GCN...
Does Crank Length Matter? GCN Does Science đč gcn.eu/4y
Does Saddle Height Really Matter? | GCN Does Science đč gcn.eu/4z
Photos: © Bettiniphoto / www.bettiniphoto.net/ & ©Tim De Waele / www.tdwsport.com
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Leave us a comment below! - Sport
Let us know your thoughts on crank length in the comments below! đ
It is a tricky thing to gauge and calculate, first off yes a good stating point is the height, then comes the weight, how much power you can output and then the most important thing is your riding style because here is how power and torque are calculated:
- Power = Torque x Angular Velocity
This means that simply having a longer crank does no mean higher torque like Adam says, it is also how you apply it, they way you stomp on he pedals, do you ride like Froome at high rpm? then short cranks will benefit as your "engine" will produce more power at higher rpm and less torque, if you're like Quintana or Contador always off the saddle putting as much force on the pedals then it will help generate higher torque at lower rpm. Both these methods will have the same outcome :
Low rpm x High Torque = High rpm x Low Torque (within reason and adequate mathematics)
Conclusion, it is necessary to take into account your riding style, the type of riding you do (TT, climbing, sprinting etc), height, weight crank arm length and these will help the amount of power you can output. It is not the case of you will produce more power but use the geometry of the bike to unleash your full potential.
I am an automotive engineer, this is a similar thing to choosing and designing engines, their configuration and application.
Show less
Global Cycling Network surely your peddling style matters to. If you've got a fast turn over or cadance you'll be better with shorter cranks I'd of though. Didn't wiggins try that out last year
Since I got my first rode bike I was 5 foot 7 and I rode 172.5mm cranks and they have just become the norm for me so I would put it down to your own perception and how you feel and what you think is right which in turn could make you ride faster if you think your bike fits perfectly :)
It is definitely a biomechanics problem, not a physics problem. My rule of thumb is that if I can cycle one legged in comfort for a long time then both seat hight and crank length will be in the ball park. Getting that crank over top is a bugger if you pedal is too high.
As a mechanical engineer, I didn't think it was fair for that one rider to comment on what I know vs a bio-mechanial engineer on suh a subject. As if we are binary and could not possibly know more than what our job description suggests.
Considering gear ratios are involved, I am not convinced that a longer crank arm will benefit you and do think bio-mechanics should come into play when considering crank arm length.
Sneaky hairstyle change at the end, Matt!
He looks younger now! :)
Also sneaky change of clothes, that Matt surely he forgot to film the last bit. 8D
Pacific Film another laughing fit, so hard his hair fell out
I had to go back to check hair length at first part of the video to that shot at the end. Looks like he went from a 175 down to a 172...
Yeah, I noticed. Nice haircut Matt.
I'm 182cm but I use 165mm cranks. They are much easier on the knees. I've had a few crashes and find I'm back on the bike much sooner with shorter cranks as I don't have to bend my knee so much at the top of the stroke. I also find there's less chance of grounding so corners and especially roundabouts can be taken much quicker.
I am 187.96cm and ride 165 cranks
Technically your hip mobility and hip anatomy would also play a role. In order to run longer cranks, you have to lower your saddle height, which means you need to have more hip flexion when your pedal is at top dead center. Then that brings you to how strong your glutes are because they are the prime movers in extension when you're in deep hip flexion. You could literally talk about it for hours lol.
I have bad hip flexors (tore each of them when I played football) and I ride 165mm cranks at 170cm height because my hip flexors won't extend enough to accommodate longer cranks without pain on longer rides
GazelleOnWheels I'm 6'3" / 190 cm and felt hip pain when I switched from 175 to 172.5 just for the hell of it. You'd think it would be the opposite.
SuperJphambone Man, that sounds like a really painful experience. Do you feel it helps at all if you tilt your pelvis forward and sit more forward like in a TT position?
Zach Bonte That's weird aha. There's probably something funky going on there. So many different factors to consider. You're probably okay with the 172.5 if it doesn't cause you pain. Basically the difference between the two would be that you need to apply more force if riding at the same cadence to keep the same power. I find what helps is usually to set up a camera beside a trainer to see if there's anything going on, etc.
is that why hansen has an extreme low position in bike, just to compensate for his longer cranks??
I love this sort of content to be honest đ
Can GCN do some blind tests on crank length please? Just to see whether you can detect a 2.5mm difference if you ride a lot.
That's the sort of change where I'd expect it to be noticeable, but 2.5mm seems a very minor difference. I'm sure I've ridden 175s and 172.5 but wouldn't be able to tell.
They have a video on that george
George Dando they already have a video on that, look up "gcn does science crank length" and you should find it.
Yes Luciano.....the link above is that video...posted almost 2 hours ago
Darren Green no, they have another video about crank length from a while ago
It does come down to biomechanics unfortunately. It's a case of do you want higher RPM or increased leg speed. And in terms of human efficiency and calorific effort, that's biology.
i love Hansen but unfortunately here I don't think he fully understands the physics. Yes a longer lever arm will give you more torque for the same force at a given RPM but by doing so you are essentially just reducing the gearing. Also for the same RPM a longer crank will require a higher leg speed, which could be less efficient.
I found your last paragraph made much more sense than your first. The former had my mind going round in conflicting circles.
There is one thing that's been omitted and that's sprocket and chainring gearing choice. Surely appropriate choice of gears would help to offset such defficiencies in either potential senario.
That Adam Hansen interview was fascinating! More of that please.
Always a great watch when I'm watching GCN videos; but I found the information here to be especially useful for me today in my fixed gear endeavors. Cheers!
What a perfect timing for this video. Just on the market for a new crankset.
Great, now I want to buy new cranks. Thanks a lot GCN
Thanks Matt. I always wanted to get an understanding of the effect of crank length and why there are different lengths.
Love the new aeroad disc matt is ridingđ
When you're young, fast, and on drugs, it does not matter much how long your cranks are.
Motors do the work.
At least some must be using motors, but they can't use that for a full stage. They still need drugs just to be competitive.
Thanks for the info guys !
That point about leverage at the end is missing the point I feel. Sure you get more leverage, but that means your legs need to move more to produce the same speed. It's not the equivalent of getting free watts, it's the equivalent of changing from standard to compact.
ik im late to this but i think his point was you need to put down less torque which would allow you to burn out your legs less. for me moving my legs faster and more is much easier to sustain than muscling threw each crank of the pedals. so this made alot of sense to me
Even later to this, but I don't think the advantage of the crank is anything to do with the gear ratio. It increases the distance between the lowest point of the crank and the highest point, allowing you to flex your leg more fully if you have longer legs. In essence it's distributing the load onto your leg muscles differently by lengthening the part of the stroke you can apply power in, altering the overall pedal stroke.
Iâm 6â1â with abnormally long femurs. My first bike came with 165mm cranks and I found myself getting knee pain and raising the saddle so much it was practically coming out of the frame. After switching to a new bike with 175mm cranks the saddle stayed where itâs supposed to be and Iâve been riding pain-free on all my bikes for well over 30 years now.
You could do a whole vid on Adam Hansen's bike setup.
Awesome informative content, thanks GCN! And Matt, you nail on it!
Appreciate it! We've done great recent content around crank length on GCN Tech đ czcams.com/video/E4BpxByalKg/video.html
@@gcn Thnx
There I've done it. I've read through all the comments for this video....now where do I pick up my mechanical engineering degree.
Most accurate point to "click here" I've ever seen on this channel. Bravo!
Super good video, well done guys
I have heard Adam interviewed a few times now, he gives a really good explanation for everything and puts a lot of thought into his answers, top bloke!
I`d like to see Adam Hansen post career get into component manufacture. I think he would come up with some interesting ideas.
He would probably re-"invent" the 90 degree crank and make up a justification for it.
This comment aged quite well
@@danloubser6133 I have the feeling he`s only just begun.
yeah, you only have to ignore the fact that Adam Hansen messes up high-school physics :D
(yes, power = torque * RPM, but as you increase the crank length (hence increase torque), maintaining the same RPM requires more effort, genius)
Iâm 6â 2â my first true road bike came with 170mm cranks, I switched to 180âs around 1990 and they felt amazing & my 2 current bikes have 180 & 177.5 respectively, to be honest I canât detect much difference between these two lengths but I tried a demo bike recently with 170âs and the circle felt really small and I didnât like it at all. I always have to special order the long lengths when I get a new bike though, but itâs worth it to me.
Pro bike mechanic for 20+yrs.
It's worth thinking about everything in this video plus the latter mentioned riders cadence/pusher of a gear or spinner etc & riders style to determine the individuals correct crank length. From there a formula can be used, it's also worth noting the pro riders comments as a lot of scientific sence is talked about & very relavent on this subject.
Basically don't assume your crank length but see someone with the correct knowledge who will asses you to determine.
A good % of my bike fit customers do ride the incorrect length as this is evident on feedback received from them to my questions plus body measurements, type of riding etc.
6 and a half minutes in: Matt finally gets a fresh haircut :)
theoretically longer crank means a longer lever sp easier to turn the gear but tbh you could use gearing to achieve a similar result, thing is for crit races youd want shorter cranks cos then you could happily pedal around tighter bends without fear of the pedal grounding out on the bend. Ultimately for me price is the issue, there is no way im gonna spend another 100 quid on a new set of cranks just because theyre a little longer.
I'm 186cm and ride Rotor3D+ 150mm cranks on my trip set-up. My FTP went up, so did my cadence and my aero position is more aggressive. Loving it.
Look at that haircut! Magnificent!
I my eyes have seen the glory.
Campagnolo used the make 165 - 180 back in the NR days, and where I worked we stocked all sizes. Shimano only offered 165 plus 170 - 175. Once the click shift thing took over, Campagnolo reduced their crank length offerings. Sugino and TA still offer a good range of sizes, although they don't pay anyone to use their stuff. Back in the 70s and 80s the rule was bump up a crank length size for CX and TT events as your cadence was lower. On the track most rode 165 as spinning was preferred over stomping. Pursuiters rode a bit longer cranks than sprinters.
I really hope that Adam Hansen writes a book after his career. In fact it needs to be a series of books. I will gladly pre-order the whole set now!
I've recently just bought a custom bike with 170mm cranks, my previous bike had 172mm cranks and already I'm getting new PBs on segmants I was riding regularly last year.
matt 's hair swag at the end!!
Surely biomechanics is more important that the leverage from the crank because the torque going to the wheels will vary with the gear you are in?
Yes you're right actually. I don't mean to defame the man, but Adam Hansen might have preferred longer cranks because he is a taller rider, and he just confused that with a new maths formula he just learned. Biomechanics matter more than just the torque the cranks can put out.
Very good video!
Love the hair Matt
I could listen to Adam Hansen all day. More Adam please
I do hope you're being sarcastic!
Well, I find him a bit difficult to understand.
I'd really recommend reading Mike Burrows' thoughts on crank lengths. He convinced me, and I'm moving to shorter ones, although for his theory to work, you also need to reduce gearing...
Very very interesting!
I'm a very short rider of 160cm but have always used 170 cranks - when i got into cycling 20+ years ago I knew nothing about different lengths and just went with what came with my bike. Not long ago I decided to experiment as common sense said I should be in shorter cranks so I bought some 165 cranks for my road bike. It only took a few rides for me to realise that despite being able to raise my saddle slightly I felt under-powered and my performance for perceived effort was noticeably less. So I'm back on 170s. They're probably too long by any "rules" but it's what I'm used to. Probably the fact I have a low cadence (usually 79-83rpm avg over a ride) is part of the reason. Anyway - 165mm Dura Ace cranks are for sale ;)
Hansen's mechanical engineering reply gets it spot on...which is why I (at 175cm tall) use:
165mm cranks on the track bike - high cadence means plenty of torque (plus shorter cranks for the banking)
170mm cranks on the single speed - for commuting so comfort over power
172.5mm on the road and TT bike - lower cadence but more torque transferred to the drivechain
Have contemplated 175mm cranks on the road/TT but feel like they'd be too long, especially if the "magic formula" says I should be on 170s.
cranks all depend on height, purpose of riding (climbing, speed, etc), leg length, position on the bike, whether you stand or sit more often, sprint, etc.
I'm all about top speed sprinting. so I don't sit too often, which the crank doesn't affect knees. I'm 6'1". a bigger crank provides better leverage, slower acceleration but higher top speed.
most people think you're disadvantaged with a bigger chainring/crank. on a straight track, you may accelerate 10 seconds faster, but within 1 minute I could zoom by you at a top speed. once I reach a higher speed, the effort is reduced dramatically. I could be pedaling with minimal effort to hit 40 kph, while you'd be pumping at 130 cad. the disadvantage is a track where you're constantly stopping.
so everything is relative to everything.
the taller:bigger a person is, the more predisposed they are to greater power. an average healthy 7-8 ft tall man, could be as strong as a pro weightlifter at 5'5".
Probably not for the pros with custom fits and plenty parts options, but for us, enthusiasts, bike fit is also another factor - if you want your knee directly above the pedal spindle at the 3 o'clock position, and the saddle is at the end of the rails, crank length is the limiter..... and nice haircut at the end, Matt
I've seen a study that proved there is not much difference in power output even with very short crank lenght like 140 mm. The longer leverage does not have so much effect because of gears. I use 155 mm cranks with my recumbent bikes. I feel it's more comfortable. But even with upright bikes, short cranks have some advantages - they are lighter and riders position can be more aero.
But in the end it's all about what do you prefer.
Good one Matt
love Adam Hansen...total legend
This was really interesting. One observation is that if a rider ascribes to biomechanics as their primary guidance, they will likely err on the side of shorter cranks to maintain cadence. Conversely, a rider considering pure mechanics may prefer longer arms for leverage.
My first bike had the standard Campy 170 cranks ( I'm 1.77 m tall ) and I always felt like I was spinning and going nowhere ... it was frustrating... By chance I broke on of the cranks in a sprint, and my mate gave me a set of 175's to use... difference was like night and day, changed everything. Actually went to 177.5 's which were great for going uphill but hard on my lumbar, so went back and been happy with 175's for the past 35 years
165mm cranks are readily available. I'm a huge 5'6 and have a 105 on winter bike, sram red on summer bike. Both in 165 length, and both were in stock online when I ordered. Good point about leverage... I've tried a 160mm length crank and although I liked the fit of the crank, I found it too difficult on steeper sections, 12% plus, of climbs. That loss of leverage is really noticeable out of the saddle, although, I guess more gears could fix that. Also, yes, it did affect style of riding. The shorter crank required an easier gear selection on the rear and increased cadence to maintain what I could do with the 165mm crank.
the new haircut is a winner matt
My power was slightly better going back2back from 170 to 172.5 - it also felt a little easier to sustain smooth power delivery. seems crazy but I was able to do this back to back with a power meter. Sold the shorter cranks to some TT hipster and kept the rings.. worthwhile test imo.
I'm 5'7" (30" inseam, but not sure about my bone lengths) and have ridden 170mm cranks for years. A few bikes ago, I tried out 172.5mm cranks.....I felt like I was a little more powerful on some climbs, but overall, my hip angle closed a bit due to the lower seat height and my cadence on the flats dropped significantly. I went back to 170mm cranks and was much more comfortable.
Nice hair cut mate 6:45
I have not read all the comments, so I don't know if anyone has mentioned this already, but anyway.
Along the travel from the position where the cranks is "pointing up" to where it is "pointing down", your knee produces more power where it is more extended. Therefore, the shorter the crank, the less your knee will bend (because the highest and lowest points are closer), and the longer it will be within optimal "power/angle ratio".
Does this make sense? It does in my head.
Of course, a longer crank produces more leverage, but that is the mechanical side.
The bio-mechanics of the knee, on the other hand...
went down 5mm and boi my legs love pedalling now! such a massive improvement!
I'd like to see the next vid then. Interested by interview with Adam. I am 183cm and just ride standard 172.5 that came with bike. That said how much difference does it really make and is it worth the money. Although I generally find when replacing chain rings it's as cheap to buy a whole new chainset
Please make a weekly/monthly segment just talking to Hansen, what a knowledge guy! He's just blew that height to crank size theory well out the water using science!
I'm afraid he didn't
Gears offset any difference in leverage (from Cranks) to achieve the same "mechanical" advantage as longer cranks, use an easier gear! Exact same effect.
See @Nick Kukoreko's comment
GCN also agrees with this in another video they did, I will see if I can find it for you
I had a lot of respect for Adam Hansen before this interview. I think he was way off the mark with his comments, as @JBMP pointed out as well as a few others in these comments.
I'm afraid he did.
Switching to a lower gear DOES result in less effort that Adam was referring to as his advantage. It does NOT equate to the same speed difference you are implying. Nick's point (& yours) only address the amount of leverage/force required to turn the cranks a full revolution.
What's not being included in that, is the slightly (VERY slightly) difference in distance traveled for that complete pedal revolution. A smaller gear does not spin the tires the same amount (distance traveled) as a larger gear. One revolution is going to have a "micro" difference regarding the distance, but after adding up 90-110 of them per minute for a few hours, it can make a significant difference.
SO - if I can have increased leverage (meaning less leg strength/torque) required to spin my wheels the same distance (because I was able to stay in the higher gear), then a longer crank is more effective, as Adam said.
@Jeff Englin You are entirely correct in saying a longer crank means greater distance travelled per revolution. This does NOT however mean more leverage. This means a longer pedal stroke. Some riders prefer riding at 90RPM, while some prefer 110RPM, there is no optimal.
Therefore a longer crank does mean more distance per revolution, but this is not the same as leverage. Torque=distance*force. Increasing the sprocket the rider is on increases the torque at the wheel, while increasing the crank length increases the Torque at the crank. Both have the same effect in terms of leverage
That video should have been called, what is the effect of Matt's different hair length? Loving your work though Matt!
I am 6'5" or 195cm, I use 172.5, 170 and 175 on my 3 whips. I will say I love them all but the 175 is very new to me and I like it so far
always find Adam Hansen fascinating
AndronicasLion his 13 consecutive Grand tour streak, puts him in the know!
16 consecutive finished GTs currently.
Ever since my XL Surly Moonlander came with 180mm Surly crank arms, Iâm totally hooked on longer. Iâm only 6ft, barefoot, but am all leg. Iâm currently looking to replace my 175mm on my gravel bike with a 9 speed triple 180mm. I might even go with a 185mm, but thatâs a couple hundred more dollars. I find I have no problem with spinning at high rpm either.
I was all along using a 170mm length. But Storck Markus himself had asked me to use 172.5mm and i never looked back. Improved my power and riding
Surprised that no one has figured this out yet. This is mainly what sets team Sky apart from the rest. They run specific crank lengths based on the course or strategy. The crank length you choose can significantly impact your power output and most importantly in the TDF, recovery time.
Totally agree crank length is a massive factor in power delivery,yes gears make a difference, But to match the extra free torque from longer cranks you would need to pedal faster in lower gear, thus placing greater demand on the cardiovascular system to match the free torque your getting from longer cranks. No brainer longer cranks rule!
''When it comes to pumping, size really does matter, but bigger isn't necessarily always better. So you might find that if you've got a big one it's quite hard to conceal, and doesn't look particularly pretty either. On the other hand if you've got a smaller one, what you might find no matter how you use it, how long or hard you go at it, it just doesn't get the job done effectively''
I bought a second hand bike recently and the seller threw in a spare compact chainset along with it. Crank length is 172.5mm compared to the 170mm standard chainset that I normally use. Going to swap the chainset over tomorrow to see how it feels.
Wooooow... Guys you should get Adam Hansen for an edition of GCN Does Science!
Adam Hansen seems very intelligent, would be good to have a video of him giving tips for future pro-cyclists. Fascinating to listen to him
I got a 'these go to eleven' vibe from the conversation. If you want to reduce the torque needed to sustain a given power, all you have to do is pick a lower gear.
I have a 56cm trek madone with 300mm cranks. they drag on the ground and gouge the cement when I pedal but damn they're torquey.
crank lengths and Qfactor are personal choice. My road bike is 172.5 and shimano standard Qfactor, my enduro bike is 175 and narrow Qfactor (bb30), I feel more comfortable sprinting in the 175/bb30. I am 178cm tall. The key question for average user is saddle/feet position. The feeling on the corners may change between crank length cos the feet high over the ground
I'm 1,74m tall, I used to have a crank of 170mm in my first bike, and now I have 172,5mm in my current roadies. Both measures are PERFECTLY usable in all the range, BUT.... the differences exist, although are far from obvious. The 170mm crank favoured me in maintaining high cadences, making it easier to sustain over 120rpm when sprinting or for example going downhill even if I got no more gears. The problem is that I'm tipically not a spinner, but more of a masher in my humble amateur cycling style (I have good strength in my legs but my heart and lungs go to very high frequencies rapidly when doing high rpms). Now, with the 172,5mm cranks I think I got the best of me: I can do my best delivering torque to the cranks in the average-to-low RPMs I'm more confortable to do most of the time, even if sacrificing just that little above 120rpm (that I can't handle for so long time), and I can deal with it now with longer transmission ratios just when I need to get those high speeds (like 52x11 or 53x11).
we use gear changes to make pedaling easier, but if you have more leverage you can pedal a bigger gear with the same relative power. All that being said, efficiency is a different story altogether
Another factor is the longer crank length reduces the seat set back (by the extra length of the crank). Made a big difference to me once on a Giant TCR (I'm 183 cm). I believe the correct crank length depends on the bike geometry and the riders leg dimensions.
It's always a trade-off because if you go to a shorter crank your knees won't need to work as much but it will need to work harder. The longer crank will give you more knee flex and leverage. I have a 30 inch inseam and I find 172.5's comfey.
'For relaxing time, make it... Hansen time."
Love this guy's take on cycling.
6 foot tall, 160-165mm cranks. This allows me to get more aero while keeping my hip angle open to generate more power. Also my saddle is slightly lower for even further aero improvements.
On a road bike I like 175, especially for climbing out of the saddle just for leverage alone. But on a flat ride I like the shortest possible, my thought being the shorter the radius of the crank the shorter the circumference of the circle the pedal is in. More rpm equals more speed. That's my thought on it anyway
i'm 6'0 and use 175mm cranks on my road bike and thats here in the mountains in NC. I'll do several centuries and 100k's a year.
but I much prefer smaller 172 or 170mm on my mountain bikes. when i have the larger cranks on the mountain bike with the lower gearing I don't feel I get the pull I need with larger cranks especially going up climbs. Some mountain bikers claim smaller cranks clear obstacles easier, but Ive never had a problem clearing with 175mm cranks
181cm tall, usually ride 175mm, but one road bike with 172.5 mm [now feels short]. Went out on my fixie without first noting its 165mm. Was miserable. To an extent you adjust all positions[seat ht-fore/aft,stem,drop], to optimize with your bike, and its what you get used to. All set for an experiment with 177.5mm in the spring!
To reduce the dead effect between 11-2 clock I use 165mm and I am 5'10. This also reduces pain when trying to put power at 11-2.
nice haircut, bro!
180cm here. i used to ride 172.5 crankarms, but couldn't get my cadence where i wanted. it always felt like i was pushing a bigger gear and i got tired more often, especially on climbs. dropped down to 170's and my cadence improved, my comfort improved, my climbing improved, and my endurance improved. plus, i got to raise my saddle 2.5mm meaning a bigger saddle to bar drop hence i gained some minor aero advantage also. it really is a matter of comfort and efficiency.
I'm 182cm bought a custom.bike with 170mm cranks normally ride 172 or 175. I find the circle small but my cadence has improved, as my cadence improves so does my issue with getting numb feet..
I love the way Adam has put so much logical thought into this. Brilliant!
It all wrong thought though, which makes it a bit sad.
Pretty much all of his maths was wrong. Pantanis legs arent 40% shorter than his, its about 8%.
His "mechanical engineering" stuff is wrong aswell. He doenst understand the physics it seems.
People will argue until the end of time about this! So many different schools of thought on the mechanical vs the biomechanical science. All I know is; I'm 174.5cms tall, I own 2 TCR's (both the same size) with 170mm cranks on one and 172.5mm cranks on the other, and I feel much more comfortable and efficient on the 170mm cranks and always a little out of place on the 172.5s. I guess it really just comes down to what feels best for the rider?
I have always wanted to give some really long cranks a try. By that formula, I should be riding 188mm cranks, and I have very long legs, even for my height, so that would suggest even longer.
The problem is that even 180mm are usually only available in expensive versions (no 105 or Tiagra), so I have no practical way to even find out if it's better for me.
In the end is a matter of preference or intended use. The riders legs are able to produce a fixed amount of peak power. If you use longer cranks, your cadence will be lower compared to shorter crank in order to produce the same power, and vice versa. Probably, a longer crank is better suited for climbing, were a lower cadence is more common.
Although the force needed is less with longer cranks, you have to move them a further distance so the power phase is longer. Does make some sense as the power is less "peaky".
When younger and racing, the emphasis is mostly if not exclusively on the mechanical performance benefit of producing more torque with a longer lever with less energy. When you're older and lot racing, the priority needs to shift to biomechanics and the longest possible lever is not as important...
Rider height aside, it also depends on where your muscles connect to the bones. Some riders may have power advantages at certain positions. I'm quite sure all these teams put these riders through stress tests to find this out.
5'11", 32" inseam = 165mm cranks for me! my hip joints love em and if my joints are happy and I have no pain! That means I can ride farther and fasster!!! Everyone is different and that's why you have to find what works for you!
I have a track bike with 165mm and a race bike with 175mm and I say the long ones feel smoother, but you need shirt on track for manoeuvrability
depends on the individual physics of a rider,cadence and what your knees are willing to work
if you want a low/slammed/Aero position, don't go with long cranks 180/177.5/ or 175s. that extra 2.5mm could be your knees bumping into your stomach
I'm 182cm and ride 165mm cranks. Used to ride 170, always felt a bit too long. Bought a brand new bike with 172.5mm cranks and literally could not get the power down. Switched to 165mm and my power output went through the roof (ok not quite, but it was higher and felt much more natural).
Think it's because I have very long lower legs compared to my femurs. EveryBODY's different ;D
With shorter cranks you can spin faster, so you can produce the same amount of power. Also, longer cranks can cause knee pain. I try to slam my stem, but in low position there is not enough space for my legs, I feel that shorter one would be better!
One detail that get's left out often is rider's flexibility and range of motion. Some riders have less range of motion in the TDC portion of the pedal stroke making it harder to set their legs up for the down-stroke of the revolution. Also, the "dead spot" covers more travel on longer cranks which means that sloppy pedal technique is more pronounced on longer cranks.
This is the gist of it! Why are we comparing ourselves to pros when most of us have the flexibility of planks?!
actually pro cyclists aren't all that flexible, they have one of the poorest flexibility amongst pro athletes
My best years were on 180mm. Good for cornering, lower centre of gravity, and no need to get out of the saddle out of the corners. Great for rolling a big gear over cobbles. Great for a massive jump from a stalling sprint, and no need to change gear during the sprint (of course in my best days your levers were on the down tube!). I'd go back to them now, except they are hard to get.
Awesome !
Got to love Adam!