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How to get cranks chainline to match old 110mm hub spacing?
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Hope you guys can help out - I picked up an old track bike and am trying to put it into service. It has 110mm rear spacing (although the previous owner fitted a 120mm hub - I had to bash the axle out of the frame with a mallet..... It was used on the road so hope he never had a puncture!!). I'm removing spacers from the hub to 110mm to suit the frame.
According to Sheldon here http://www.sheldonbrown.com/chainline.html the rear chainline should be "towards the low end" of 40.5-42mm, but I measure it at closer to 38mm. The sprocket seems to be fitted the right way round, with the teeth on the outside.
It currently has a nice Ofmega chainset but I measure the front chainline at about 42mm, so quite a big discrepancy from front to rear. I did notice the chain was pretty noisy.
Anyway, I want to change the chainset to a Sugino XD2 I have floating around (the Ofmega arms are 170 long so not velodromable, the gearing is all wrong & I don't have any 144BCD chainrings). Sugino recommend a 110mm BB axle to give a 45mm chainline, so if I use a 103mm BB that should give me a 41.5mm front chainline. Although I'm not even sure this will work without a chainring / chainstay clash (but the fitted Ofmega is a 52T and I'll be running a smaller 48T so should get away with it?!)
Question is, that still leaves me with what seems like too much difference between front & rear chainline :-
How come my hub chainline is so much narrower than normal (according to Sheldon)?
Has anyone else had issues with a narrow chainline on 110mm hub spacing?
Is there a sensible way to change this? Would fitting a spacer behind the sprocket on the hub still allow the lockring to be fitted properly - is this normal practice or a no-no?
Any other practical ways to get narrower chainline at the front - are there any track chainsets intended for <40mm? (eg I checked Sugino Messenger on their site and that quotes a 45mm chainline with 103mm BB axle, so wider than the XD2)
Thanks for any pointers!!
Cheers,
Richard.