Square taper compatibility
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Square taper compatibility
I may be taking my 83 Gitane Interclub to Eroica California. In order to get a bit more hill-friendly gearing, I've swapped the original Simplex SX410 rear derailleur for a Suntour V-GT Luxe so I can use my 14-34 freewheel.
I'd also like to swap the bike's original Nervar crankset for a Stronglight 99 and build a "retro" compact crankset. Does anyone know it the Stronglight crank's taper with work with the bike's original Nervar bottom bracket taper?
I'd also like to swap the bike's original Nervar crankset for a Stronglight 99 and build a "retro" compact crankset. Does anyone know it the Stronglight crank's taper with work with the bike's original Nervar bottom bracket taper?

Last edited by Brad L; 01-06-20 at 11:48 AM.
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Thanks. I've seen the Sheldon Brown article on the various tapers, but in the ISO category they list Nervar together with "older Stronglight." I wasn't sure if the Stronglight 99 crankset would be considered "older" or "newer" Stronglight.
#4
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While there are guidelines and measurements, the truth is you will never be 100% sure that your crank or taper corresponds to some standard, so the only true way to know is to try. The good news is the tapers will always match - it's mostly a matter of chainline and frame clearance, not total incompatibility.
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Mostly. You are staying French so the chances of extreme mismatch are minimal
check the chainline with a true straightedge before then after you install the 99 crank- remove the fixing bolt and note the spindle engagement.
try the 99 before you purchase rings.
after you attach and secure that- remove the fixing bolt and observe the engagement - check the chainline.
you do not want less engagement and not so much that the spindle extends to the washer.
chainline can fudge- note that in the small/ small the risk of catching the big ring increases if the crank set is too far inboard
check the chainline with a true straightedge before then after you install the 99 crank- remove the fixing bolt and note the spindle engagement.
try the 99 before you purchase rings.
after you attach and secure that- remove the fixing bolt and observe the engagement - check the chainline.
you do not want less engagement and not so much that the spindle extends to the washer.
chainline can fudge- note that in the small/ small the risk of catching the big ring increases if the crank set is too far inboard