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Old 05-29-18, 09:13 AM
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dddd
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If this frame has decent chainring clearance then a Chorus or other 1990-ish Campagnolo crank might play nice with your existing setup.

Those mostly used the 111mm bottom bracket with similar taper, so the crank would likely only move in about 1mm from where that bottom bracket positioned the arm and rings. Most frames have a lot more clearance at the chainstay than that, even with standard 42t or 39t inner ring.

A 7410 Dura-Ace crankset used a 103mm JIS bottom bracket, so with the narrower Campagnolo spindle would sit within a mm of where it is supposed to. You might have to grind a couple of mm off of the ends of the spindle in your frame so that the bolts don't bottom out before the crank achieves a good press-fit on your spindle.
The difference of taper will have a JIS-taper spindle acting like it is about 2.5mm longer on each end versus the Campagnolo taper.
You would have to shield the bottom bracket bearings from dust resulting from grinding, and I don't think that the inward end of the taper will interfere too much with the edges of the bigger end of the opening in the crankarm.
I've done this and used a 6" grinding wheel on an electric drill mounted on an arbor accessory made for this purpose. I only needed to grind of 1mm in my case and the bolt never bottomed out on the end of the spindle.
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