Hi there.
I’m building up a Charge Plug ‘cross bike and i’ve a question regarding chainset spec that I hope someone can help with.
Most of these cross bikes with 135mm rear spacing come with road double chainsets. I’d like to run a set of Middleburn MTB cranks with the inner ring removed.
The reason for this (to my understanding anyway) is that the chainline of a 135mm rear hub is suited to a MTB triple rather than a road double. If I take the inner ring off the Middleburns and buy a slightly shorter BB (4mm shorter) to compensate, my reckoning is that i’ll have a better chainline than if I ran a road double.
There must be a reason why bike companies aren’t doing this though. Is it because you can’t shorten the axle of a GXP / outboard BB? Is it because a road front mech won’t shift the chain onto the big ring (even with a shorter axle?)
I’d rather find out before I go for the Middleburn’s, but running a road double with a 135mm rear end seems a bad idea – even though everyone is doing it.
Any advice would be appreciated.
Thank you.