would a frame fit if longer cranks arms used

[cnighbor1]

would a 56 cm frame fit say a person who rides a 58 cm ctt frame with 170 mm crank arms he went to 172.5 crank arms on the 56 cm frame
I would say yes if longer cranks work for him
I ask because some times a person will say frame is just 1 or 2 cm too small and this would be a solution

[fa63]

No. The length of the crank arm does not affect the reach to the handlebar; only the saddle height. Even if it did, 2.5 mm could not make up for a 1-2 cm difference.

Also, no one measures bikes by their seat tube measurement any more :)

[seric]

A longer crankarm would move the saddle slightly down and forward a small amount to keep the leg extension at bottom of stroke and knee/spindle location identical. How much this is moved would depend on seat tube angle.

[kramnnim]

You could just raise the seatpost and get a longer stem if you were desperate...but we are picky.

[Joxster]

Or just get the right sized frame to begin with :p

[oldpotatoe]

would a 56 cm frame fit say a person who rides a 58 cm ctt frame with 170 mm crank arms he went to 172.5 crank arms on the 56 cm frame
I would say yes if longer cranks work for him
I ask because some times a person will say frame is just 1 or 2 cm too small and this would be a solution

2.5mm, not cm..170 to 172.5 plus for proper seat height, actually lowering the saddle, not raising..

[ultraman6970]

If he goes 180 mm he could gain a lot more but IMO frame will be too short anyways.

[ripvanrando]

If he went from 170 mm to 190 cranks, maybe.

I've ridden 200 mm cranks and the saddle goes down but the setback also changes. The Trig is pretty easy.

I don't think a 2.5 mm change in crank length merits much more than a tiny little shove down on the seat post but then again some riders are sensitive to very slight changes. I'm not. Saddles on the other hand can be 10 mm different in height and that is enough to mess me up