I bought a second hand SunRace MX8 and the chain is slipping on the 11t sprocket, tried all sorts to get it to work but couldn’t until I tried an 11t from an XT cassette (which works fine). I’m trying to buy just an 11t M8000 sprocket but can’t find any, I have found an XTR one from SJS, but will it be compatible with the XT cassette and hence the SunRace?

Yes

Doubtful the 11t is worn enough to slip as it’s probably the least used sprocket unless previous owner was Chris Hoy. I’d be looking at gear set up, rear mech hanger alignment etc before splashing out on an expensive cog

It could be the sunrace lockring for the cassette is slightly larger in dia than the xt version and stopping the chain connecting with the limited number of teeth on such a small sprocket – I’ve had this problem before with certain combinations of drivetrain parts.

rOcKeTdOg – Member
Doubtful the 11t is worn enough to slip as it’s probably the least used sprocket unless previous owner was Chris Hoy. I’d be looking at gear set up, rear mech hanger alignment etc before splashing out on an expensive cog

Wrong, it’s always the first sprocket to wear on my cassettes and I’m no Chris Hoy. Least amount of chain wrap and reasonably strong legs

Virtually a brand new bike and I tried the xt lockring, calibrating the gears and nothing worked. Switching to the xt 11t immediately fixed it. I can only assume one of the teeth was damaged or just worn. The rest of the cassette is fine.

I will get the new sprocket.

Wrong, it’s always the first sprocket to wear on my cassettes and I’m no Chris Hoy. Least amount of chain wrap and reasonably strong legs

you need a bigger chainring so you can use the entire cassette then

rOcKeTdOg – Member

Wrong, it’s always the first sprocket to wear on my cassettes and I’m no Chris Hoy. Least amount of chain wrap and reasonably strong legs
you need a bigger chainring so you can use the entire cassette then

Moved to a 36 tooth, for a bit. Big climbs fatigued me. Might try again but with a bigger than 42 on the rear. Can’t go double on the front as it’s not compatible.
Mostly I’m trying to change my style to spin from mash.