Brad L 

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?

TenGrainBread 

Short answer: They are compatible

Long answer: This thread: https://www.bikeforums.net/classic-v...jis-taper.html

Brad L 

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.

TenGrainBread 

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.

repechage

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