Chainring spacing

chrisga

Can anyone tell me, or point me in the right direction (on this occassion gooogle has let me down), the spacing between chainrings on a triple shimano chainset.

I am in the process of changing from a triple do double with bash. However, and i may be being over the top here, i'd like to keep my chainlines as nice as possible, so in my head have it in mind that i need to move the driveside crank out to compensate. I.e. make the middle of the gap between my granny and middle ring be on the same line that my middle ring was on previously if that makes sense. Is this over the top or is it the right thing to do?

I am putting an order in with crc and so some spacers to go behind the bb cups wouldnt break the bank. Just dont want to get halfway through the job and realise i need them and cant get to my bike right now to measure it.

Thanks,

Chris

nicklouse

dont bother, no one else does.

it also may create more problems than you think it may solve.

chrisga

Ok that helps. Thanks.

Just out of interest what issues would it cause? Front mech alignment problems?

cooldad

From a purely mechanical point of view, the less leverage on the crank spindle the better.

The Rookie

As the middle ring of a triple on an MTB is usually set up mid cassette, and I doubt you use the granny ring more than 5% of the time, I'd leave well alone.

Otherwise if you really want to get an axle 5mm longer than current (moving chainline 2.5mm) assuming you have a seperate BB not something like a Hollowtech.

Simon