Join Date: Jun 2009
Location: Dallas, TX
Bikes: Panasonic NJS Keirin x2, Level Professional, Bianchi CUSS, GT Pulse
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What taper is your spindle? How old are your cranks? Chainring type is irrelevant for this issue, but remember, installing and removing a square taper crank frequently will enlarge the hole ever so slightly.
As far as spindles, A JIS taper spindle will fit an ISO crank arm, but sit about 4.5mm out. Conversely, an ISO taper spindle with a JIS crankarm will sit 4.5mm closer, and sometimes the taper will never allow you to fully tighten the crank arm before the bolt bottoms out.
If you're using messenger crank arms, those are JIS taper. Make sure you don't have an ISO taper spindle in your current bb.