i posted this in the bike mechanics section too, but maybe you guys can help out too as the cranks i am using are bmx/track cranks

so i have a 103mm BB spindle and a sugino crank that says should use a 110mm spindle, i put it on the other day and it didnt bottom out against the BB casing or anything and goes on and comes off smoothly and rides smooth. just wondering what the problems are with this if there are any? the only difference i can see is that you would have a lower q factor. i know that you are not supposed to do this though. thanks

Your chainline would be 3.5 mm off, I think.

What crankset are we talking about here?

i am using the sugino xd2 crankset

i didn't think xd2 was a bmx/track crank...
they recommended mounting it on a 107 to 110mm bb because was meant for multiple rings

Yeah, those cranks were originally designed for touring, tandems, and mountain bikes. The recommended spindle length is given with the assumption that the cranks are set up with two or even three chainrings.

Cheers
lverhagen

oh. i got them from a friend who replaced her crank on her republic fixed gear bike. i guess they came stock on it so i didnt even think that they would have been touring cranks.

They came stock on that bike since they are incredibly common and inexpensive (not to mention fantastic) cranks from Sugino. They are also very versatile, as you have discovered. I wouldn't be afraid to put those cranks on any bike I own since they are reliable, have common bcd sizing (110/74), and look good without being flashy. Anyways, best of luck!

Cheers
lverhagen