On my shimano 2300 8 speed gear set I replaced the chain after it started slipping. Thing is the new one has failed twice (bent links, failed pins). Repaired the bad links with some 9 speed links left over from my mtb chain. They fit in fine and work great. They look almost the same size as well.

Thus... would my drive train care if I dumped this weak chain and just put in a quality 9 speed chain? Its getting harder to get quality 8 speed chains these days.

No harm.

Your drivetrain might even perform slightly better.

IDK about retail in Korea, but in the states there are nice quality chains available to us in all widths .

Rohloff and Whipperman from Germany make 3/32" bushingless derailleur chains .. ie 6,7,8 speed ..

KMC is OK , I think they are a Taiwan company.


NB , perhaps just replacing the chain is the problem , you left the worn cog teeth in place ,
buy a new freewheel or cassette and the chain together.

No. Replaced the 12-25 with a 11-34 (an adventure in itself!) at the same time. Besides worn teeth don't bendinks like pretzels.

here's the difference (courtesy of wikipedia)

• 6 speed - 7.8mm (all brands)
• 7 speed - 7.3mm (all brands)
• 8 speed - 7.1mm (all brands)
• 9 speed - 6.6 to 6.8mm (all brands)

Don't take this as gospel, but it's a good guideline for comparison. You'll note that there's only a very tiny difference between 7s and 8s chains.

There's also a decent amount of latitude, but here are the drawbacks to going off spec. Wider chains are more finicky about trim in the rear, and more likely to brush the outer chairing when coming from the outside rear to the inner ring. OTOH narrower chains can sometimes snag behind the teeth of the inner chairing when downshifting.

So feel free to fudge, and if you don't have problems so much the better. But if you experience problems you know why.

"On my shimano 2300 8 speed gear set I replaced the chain after it started slipping."

Maybe, since the RD-2300 spec's a max 26T cog size, a 34T cog just MIGHT be causing problems?

I'm not sure what your options are in Korea but over here there are still plenty of options for a good 8-speed chain. I can pick up a nice KMC or SRAM chain on ebay with a replaceable master link for $13-20 all day long.

Actually the 34 works. I was shocked but it works. If you go to Shmanos website they list the 2200/2300 as supporting up to 30t. Bit of a stretch but thats what I do best. Chain tension is fine and theres no circumstance I xan think
if that would twist a chain link 30 degrees off kilter unless its weak to start with.

Phil Shop Korea is a great resource for stuff like this. (They even sell Chain-L).

You can shop the site if you can read Korean, but the owner Phil speaks excellent English also.

I WENT to the Shimano website!
https://techdocs.shimano.com/media/te...9830673817.pdf

It supports 30T of chain wrap.

And it works just fine. The only issue possible is the guides.and the gear meshing...which they do not.

I've been running a Sram 830 on my 9 - speed xtr. Main rub point is when in small chainring and second biggest cog. The chain rubs on biggest cog a bit but hasn't snagged or ghost shifted yet.

Went to the 830 after snapping a KMC 9.93, IIRC.

Got a Sram 9sp chain but dunno if I'll use it on this bike, since the 830 works so well.

Thanks for the info. I got a 9 speed dura ace/xtr chain and tried it out. Smoother, shifts better, and allows for tighter tolerances.