Crank Length Question

[Ally]

Could I canvas opinion please?

I run 175mm's on my mountain bikes and 172.5mm's on my road bike, both feel fine to me.

I'm away to be building up another road bike and can only find the cranks I want in 170mm length. Compared to what I'm used to on the road, its only 5mm diameter difference.

I've never used this size, but do you think the difference is particularly noticable? Pro's and Con's?

I'm curious, so I may well end up just trying 170mm's to see how they feel compared to what I'm used to.

Thanks in advance folks.

 

[dbmtb]

What size bike do you ride and how long are your legs?

170s will make you spin faster and if your proportions are better suited to them, will make you less tired.

 

[velomaniac]

I personally cannot feel a difference in cranks between 165mm - 175mm despite the fact I'm very tall. Mind you I'm not hugely athletic so long term effects are not apparent. I doubt though that you'd notice a 5mm difference on your road bike

 

[Ally]

Good point.

I'm 5'11", 32" inside leg, frame is 56cm. Pedal with a slightly slow cadence; around 80rpm.

The more I think about it, I think I'll give 170mm's a go.

 

[dbmtb]

You probably won't notice much difference.

I've got short legs and only run 170s on bikes I'll be sat on for more than a couple of hours or there's hell to pay the day after.

 

[Don't walk]

I think most road bikes come with 170s anyway as you tend to have a higher cadence on road than of it. I only notice a difference with crank lengths when there is a significant difference i.e more than 10mm difference in crank length.

 

[Ally]

Thanks folks,

I've ordered 170mm's to give them a shot. I don't think i'll notice much difference, but we'll see.

Cheers again.