I switched after a bike fit, can’t say I noticed much difference, I adjusted the saddle height to compensate. I would need to go back to 170 to compare, which I am not planning on doing. Ordered a new bike this year and went with 165 to keep the same. Bike fit also suggested stem length increase by 10mm. This is on my new bike and does take some time to get used to.
I’m 6’ (183 cm) tall and I went from always riding 172.5 or 175 mm cranks straight to 165 mm on my road bike last year. It helped me get significantly lower on the bike and got rid of some low back pain. I won’t go back.
On the mountain bike I’ll be sticking with at least 170 mm because I like having more leverage from the longer cranks for steep climbs. Hip angle doesn’t really matter there but avoiding rock strikes does.
Gravel is more debatable and depending on how low you want to go with your position.
Went down to 165 back in 2016b and never looked back. Could ride longer without hamstring cramping, less pedal strikes on corners, the pedal strike was just more fluid and ran off the bike much better. Genuinely couldn’t find a reason to stay with longer cracks.
Same situation and I did the same, as well as moving to 170s from 175s.
Note that reducing crank length means that your foot is closer to you when your foot is at the bottom of the pedal stroke, which means that you would need to raise your saddle a similar amount as the amount you shortened the crank. This will also move you slightly backwards.
Of course, this assumes your original saddle height was correct and was measured from the center of the crank.
But also consider that at the bottom of the pedal stroke you aren’t really doing anything useful. Where you apply power and therefore have the highest loads on your joints is around 3 o’clock. Here the shorter crank moves the pedal backward and while it will also close your knee angle slightly, more appropriate adjustments might be moving the saddle back or the cleats forwards.
Based on the anecdata of dozens of bike fitter YouTube channels, saddles seem to be mostly too high anyway. I suspect many of these are to clear impingement at the top of stroke, and shorter cranks reduce this problem allowing the seat to be lowered to a more stable location.
Unfortunately, the bike industry’s refusal to scale crank arms means we locked ~170mm cranks into ~73 seat angles that are instead steepened or slackened. A broad shift in crank lengths might really need a different approach to seat angles.
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I’m 170cm tall and 66 kg. Best thing I ever did. Never looking back.
I had a bunch of different crank sizes on different bikes (145-172.5 or 175, not sure). I didn’t notice the difference in pedal feel between them.
What I did notice on the shorter ones was the higher center of gravity. And on the longer ones (my commuting bike) I noticed clipping my pedals occasionally [never hard enough to crash, thankfully]. I guess I had gotten used to the clearances on my other bikes which were all shorter (165 or less).
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I recently went to 165 on my epic evo and I’ve enjoyed having less pedal strikes but its raised my center of gravity up which has taken a bit to get used to. Im thinking of going back but Ill give it a few more months. Im honestly surprised more people arent complaining about their higher center of gravity and saying they feel less “in the bike.”
I was also wondering what is more aero…Raising your entire body up a half inch when you put on shorter cranks or staying lower with the long cranks and with less saddle to bar drop.
I think generally you get more aero when moving to shorter cranks because while your butt does move up the front stays the same so usually you are just flattening out your back
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I’m massively more aero with 165 cranks vs the 172.5 that came on my Tarmac. The reason is that my hip flexibility was the limiting factor in getting my back flatter. Raising my seat slightly and getting my chin way closer to the bars is a huge difference. Combined with narrow bars, I can draft small riders now. Total game changer.
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