Crank lengths - anyone gone shorter?

[Sea of vapours]

When it comes to hills, you just ride a lower gear.

My bikes have 172.5mm cranks. I'm 175cm tall, and I can pedal at 100 rpm comfortably . I tried 165mm cranks a while back, but not for long as the detrimental effect on *steep* hills was considerable. By 'steep', I mean any road over 15%, of which there are many around here in the Dales. Yes, as @Sharky says, you can just change down a gear to compensate for the reduced torque due to the shorter crank, but I'm in my lowest gear anyway, above 15%, so there is 'nowhere to go' and the short cranks made steep hills much harder. Up to about 10%, the 165mm cranks were fine, but for me not really better in any way, so it was all downside.

 

[super_davo]

I changed all my bikes from 172.,5 to 165 last year. TBH I always thought 172.5 was a bit long, but it came with my bike, then I had a 4iii left crank power meter in that size, so stuck with it for a long time...
Anyway I'm a massive convert now. Main benefit is I get less DOMS after hard rides, which if I'm going away for a cycling trip, is really useful indeed. It definitely benefitted my fitness as I didn't need to take so many easy days.
WRT to the less leverage and struggles on higher %... yes you can definitely feel the reduction in leverage but modern gearing has so many options now you should be able to work around (especially 12 speed).

 

[Profpointy]

I have short cranks on my fixie and prefer it, at least on the fixie, on which it also gives slightly more lean angle when cornering

 

[midlandsgrimpeur]

I had a professional bike fit in the summer. I'm speccing a new bike at the moment and the question of crank length came up. I contacted my fitter, who is also a personal friend. This was his comment:

"Hi Paul,
The only reasons to change crank length would be if you are becoming impinged in the hip at the top of the pedal stroke.
Essentially shorter cranks allow you to spin a smaller circle and have a more open hip angle.
If you can spin a high cadence without tightness in the hip then shortening your cranks will have little benefits."

@midlandsgrimpeur if you have issues get a bike fit. If the results don't suit you can always go back to your previous position.

I know Lee Prescott over at Velo Atelier who is basically President of the International Bike Fitting Institute. I will get in touch with him at some point. I suspect it may require a full on new bike fit, I guess I also have to accept I am no longer 25 years old and can contort myself into any position!

 

[Happy_Days]

Im considering shorter cranks in an effort to alleviate my ongoing knee pain saga,

I switched to shorter cranks to help with knee pain. It worked. However, I had a professional bike fit to optimise my position.

Shorter cranks, pedals with a wider Q-factor, and a bike fit – combined – solved my knee pain.

I’ve experienced no downsides.

 

[Timeisrunningout]

I switched to 165mm and would not look back. It helped sort my knee pain after a range of other attempts that didn't work...