dirtyphotons

first, yes, i've searched. i've also talked with several people i trust and have received wildly divergent advice every time i've sought it. sorry in advance for the long winded post.

i've got a nine speed drivetrain on my bike. with a mountain cassette in the back, i'm getting a little bit of rubbing in my fourth gear (the chain rubbing the next larger cog on the cassette). i've done the obvious, adjusted the rear derailleur: cable tension, limit screws and b screw. that's not it, it's rubbing on top of the cassettte. i've gotten a longer bottom bracket, which reduced the rubbing from annoyingly audible to barely noticeable.

i've ridden with the (now faint) rub for a bit now, and it's not even something most people would notice. but i know its there, and it's almost time for a new chain so i did some research into folks who've used 10 speed chains on 9 speed drivetrains, thinking that a narrower chain might finally put the issue to rest.

for the most part, people say it can be done in practice and i've found relatively few people who claim to have tried it and had difficulty with the setup, but i thought i'd ask you all.

mostly i'm looking for folks who have actually tried this and have had problems with it, as i'm more or less convinced that it's worth a shot. i know ten speed chains are more expensive and that the difference in width is small, but i can get one cheap and haven't much to lose.

so who's had problems with this setup?

stapfam

Only problem I had was with wear. 10 speed chain will work and I tried one on the MTB. Lots of torque required on parts of the ride and the chain had too much wear after about 400 miles. Normally I get 1,000 out of an XT chain (Same grade as ultegra). Then on the 8 Speed Sora with a cheap 8 speed chain- I only got 600 miles on the road.