Crank arm length

[Andrew1971]

Hi All
What is the most common crank arm length for single speed.
Many thanks
Andrew

 

[GGJ]

170mm for roads is the most common, 165mm for track

 

[Andrew1971]

Just had a look on my giant defy 5 the crank arms are 172.5 would they be ok or to long.
Many thanks
Andrew

 

[KneesUp]

Yours are only 1.5% longer than the most commonly used size - I think you'll be fine

 

[Andrew1971]

Cheers for the info Kneesup. Looks like i need a smaller front chain ring that should stop me knees hurting grinding away on a to big a chain ring

 

[GGJ]

I doubt if you would notice any difference between 170mm and 172.5mm

What size chainring are you running and what size sprocket on the rear?

 

[4F]

One of my fixed gear bikes has 165 and the other 170. Can't say I really notice the difference

 

[Andrew1971]

Hi all
Solved it I put different pedals on it there are flat ones so no straps or clips of any kind.so my feet find
their own position that's comfortable.
Many thanks
Andrew

 

[Dan B]

The biggest reason for thinking about crank length on fixed is the possibility of grounding out a pedal when going around bends. Which can be very painful, but the chance of it happening does depend a lot on bottom bracket height

 

[GrumpyGregry]

The biggest reason for thinking about crank length on fixed is the possibility of grounding out a pedal when going around bends. Which can be very painful, but the chance of it happening does depend a lot on bottom bracket height

and angle of attack when cornering.

That said I caught a pedal when bolt upright, filtering between a black cab and a pedestrian refuge kerb, in central once.

 

[Acesand8s]

The biggest reason for thinking about crank length on fixed is the possibility of grounding out a pedal when going around bends. Which can be very painful, but the chance of it happening does depend a lot on bottom bracket height

The other reason is a better rpm range, especialy for a higher rpm, smaller is better. There are legal standards for the track,bottom bracket clearance is another standard, so you dont hit the ground, and might even matter more than crank arm length.

 

[Deleted member 1258]

I'm on 165 on my fixed, I find it makes spinning up on a descent easier.

 

[kloeshuman]

where you see the difference is toe overlap, I normally run 170/ 172.5 and a new set I picked up were 175, you have to watch that

 

[Basil.B]

I ride a 165mm.

 

[YahudaMoon]

Track bikes must have a fixed wheel, 165mm cranks, and 280mm (11”) bottom bracket height
(measured from floor to centre of bottom bracket)

Here. if your riding track

http://www2.nationalcyclingcentre.com/documents/Track bike specification.pdf