Superstar Narrow/wide issues

TE

Hi all. Very rare I post on here but here goes.

I fitted a 34t Superstar I/O chainring to my Stumpjumper Evo last night. The chainline looked pretty decent so I didnt feel the need to alter it.
Anyway, it hasnt even been out of the stand yet and i can't get the chain to stay on when it's at each extremity of the cassette. When in 1st, the chain rides up the front sprocket and drops onto the bottom bracket. When in 10th, the chain rides up and off, onto the crankarm. Looking at it, this is happening because unlike a normal 'old' chainring, the chain is not allowed to defect at all on the chainring in order to move across on the high and low gears, so it is simply lifting itself off.

I have played around with the chainline to no success, and also played with chainring, but still the chain will not tolerate being in 1st/10th.

My full drivetrain is pretty much new, so nothing is worn at all. The chain is a SRAM hollowpin. The only thing I can now think of is the chainring itself is the issue. Superstar poor quality perhaps?

I've never heard of a problem, and to be honest Ive only ever heard good things! I really can't think of a solution! Any suggestions would be gratefully received. (Please, no 'have you got the chain sat on the wrong teeth?' type replies)

Thanks.

peter413

IME the Superstar rings are a little less well made than other offerings. I found the chain jumped off once or twice in the stand when it was brand new but it never did this while riding. It's also a little noisier than others I've used. It's not just me, a mate agrees that the machining isn't as good on the Superstar's. It's good enough to not cause any issues normally but it's still not as good as others. It quickly wore itself in to the chain though so it hasn't jumped off even in the stand since that first time. And in fairness it never left the ring, the chain just sat on top of the teeth which was bizarre.

I've also noticed it seems to be more susceptible to mud. I use a Blackspire on my Mega (Superstar on the Cube) and a friend uses a Superstar on his bike. Riding the exact same trail in the exact same conditions his chain would occasionally derail itself because of mud build up. The Blackspire has never done this. That could just be total coincidence though.

My suggestion would be to ride it up and down the street a few times and see if that wears it in. If not I'd shoot an email to Superstar asking for a replacement.

TE

I've just been having a good study as you were replying, and you've described just what i observed. Some of the narrow teeth wont accept the chain, resulting in it riding on top of the ring, and eventually derailling in the top and bottom gears. I reckon once the sharp edges have worn off it might work better under load than it does in the stand. Although as you said, mud could be a problem. So yeah, my top guess would be sh1t-a55 machining tolerances from Superstar...
Cheers.

TheGava

Hey, had the same problem with my superstar ring on the Bike Stand kept dropping the chain! But once riding and under load, 6 months later ive only ever dropped the chain once and this was probably due to the fact I didn't engage the clutch on the rear mech!

Now I can only recommend it!

Hope yours works just as mine but if in doubt send superstar an email ...

TE

thanks for the reply buddy. I'll take it for a spin up the road tomorrow and see how it stays. Hopefully good.

stubs

They are a bit noisy at first and when you rotate the wheel by hand in the workstand you can feel every clunk as the chain drops into place. A couple of rides and you shouldnt notice anything, if you do bang off an email you might have a duff one. Seeing as SS must have made and sold tens of thousands of these (I reckon round my way almost half of riders use them) they will have the odd faulty batch.