Hello all!

Regarding my build, a 2016 Fuji Touring overhaul/respec: I now have a complete bike, minus the shifters I’m waiting on (some super-sweet Gevenalle CX shifters). I have converted the rear to 10 sp. with An m592 RD. I lined everything up initially, and all looks good in compatible without a doubt.

Now, according to The Late, Great, Sheldon Brown, and my very careful calculations, I should have no problem running a 10 speed chain on this 9x3 crank With its 9x3 FD.

There seems not to be a whole wealth of information on this subject, so it is quite nerve racking. Here’s my thought process.

Given that the FD is operated by friction shifter, I foresee no problem with chainring spacing and indexing.

the chainline will remain the same so no problem there. And given the identical cassette width between 9 and 10sp, no foreseeable issues with chainrub are present (especially given the ability to trim to my heart’s content).

10 sp chains have the same inner width, and length (roller to roller), so the chainring will operate the chain and seat correctly.

the derailleur, being that it will manually move the chain from ring to ring and trims to my will, will also not be a problem.

i also don’t imagine the pickup ramps to be designed much different between 9/10 speed, being that the 2 chains have only a fractional difference in design (being only the outer width of the chain).

i am fairly confident that this will work exceptionally well. The problem is that the ONLY confidence-inducing information I’ve got on this very specific subject beside my own common sense is from Sheldon Brown (which is best case scenario, IMO). However, in scouring the forums, I’ve found very little. Those threads I’ve found which talk about it are very vague.

Some say it doesn’t work. Then again, none of them mentioned weather they were using indexed shifters. Being that (obviously) it didn’t work, I have a feeling that their problem was that they are using Indexed shifters to attempt this. In this case, why would I even bother batting an eye to those threads. Chainring/indexed spacing is OBVIOUSLY different between 9 and 10 sp cranks/Front mechs.

Can someone please confirm that I can use a 10sp chain on a 9sp triple crank with friction shifting and a 9sp triple FD?

thank you!