Crank Arms

[funk my fixie]

Evening all

I have heard that couriers in London use a shorter crank arm than a standard bike. Does this increase speed at all? Or is it just a way of increasing stamina as you would clearly need to push a little harder on each stroke as the lever length is shorter and the pedal is closer to the rotational axis? Either way, would it not make more sense to just go for smaller cog or larger crank? It would achieve the same objective/s.

 

[musa]

For couriers each to the own. There's no general code. Well not when I was one.

 

[rb58]

AFAIK shorter crank arms are favoured by fixed gear riders because they lessen the possibility of pedal strike when cornering. Many London couriers ride fixed wheel, so that could be it.

 

[funk my fixie]

ahh that makes sense, I have clipped the ground once or twice. Thanks for the answers guy

 

[Boris Bajic]

AFAIK shorter crank arms are favoured by fixed gear riders because they lessen the possibility of pedal strike when cornering. Many London couriers ride fixed wheel, so that could be it.

Yes, this is the reasoning behind it.

However, pedal strike is a pretty rare thing and most fixed-gear bicycles are parts-bin specials built for the square root of zip.

That being so, and the relative scarcity of 165mm cranks on the used market being what it is.... you will see a lot of fixed bikes with 170mmm cranks (or around that figure).

 

[simon.r]

These cranks are are well priced at £20, though you may need to jiggle things around a bit to get a decent chainline

(Although 165mm is currently out of stock)

 

[Deleted member 1258]

I use the Lasco chainset in 165 length from VeloSolo

http://www.velosolo.co.uk/lasco.html

I find I descend better on a 165 crank, probably something to do with my short legs.

 

[funk my fixie]

Yes, this is the reasoning behind it.

However, pedal strike is a pretty rare thing and most fixed-gear bicycles are parts-bin specials built for the square root of zip.

That being so, and the relative scarcity of 165mm cranks on the used market being what it is.... you will see a lot of fixed bikes with 170mmm cranks (or around that figure).

you can buy a 165mm from evans cycles if you need one

 

[Gaijin]

The London couriers and "hipsters" like myself use 165mm cranks.
Yes there are few reasons for that, firstly its "trendy" and "popular",
secondly, there is a lesser chance for a pedal strike as it was mentioned earlier.
and lastly I've heard that TT cyclists use shorter cranks on fixies for a spinning training.

 

[funk my fixie]

cool ta x

 

[Jezston]

Also 165mm is standard on the velodrome, I believe. You aren't allowed to use longer.

 

[Sergeant Pluck]

I thought that the reason for the shorter cranks on fixed was that it is easier to spin.

I’ve had pedal strikes in the past on a converted road bike with pedals + toestraps like wot some couriers use I suppose, but with the relatively compact clipless pedals that are used now I can’t see it being a big issue.

 

[Deleted member 1258]

I thought that the reason for the shorter cranks on fixed was that it is easier to spin.

That what I found when I moved to 165 cranks, I descend better on 165 cranks.

 

[funk my fixie]

I thought that the reason for the shorter cranks on fixed was that it is easier to spin.

I’ve had pedal strikes in the past on a converted road bike with pedals + toestraps like wot some couriers use I suppose, but with the relatively compact clipless pedals that are used now I can’t see it being a big issue.

While I know little about bikes, what I can tell you is that a shorter crank arm would be harder to turn and so spinning is harder

 

[funk my fixie]

That what I found when I moved to 165 cranks, I descend better on 165 cranks.

You probably did find it easier. You would have more control and be able to push more so MAYBE slightly faster as well.