Need Help - Chain vs Chainring not right size?
 

BFSSFG readers,

I've tried searching the forum and the internet but I can't find anything on this. I ordered a 1/8" Sugino chainring and also a 1/8" SRAM PC-1 chain from Jenson. They both claim 1/8" on their packaging. But for some reason the chain is too narrow for the ring - the chain won't fit fully down into the valleys. Now, Jenson's customer service has been pretty cool and they've sent me a replacement chain saying that the PC-1 isn't totally 1/8". However, I received their replacement chain and it still doesn't work. I took some measurements - it seems that the SRAM chain is 1/8" but that the Sugino chainring is more like 5/32" or at least wider than 1/8". I need some opinions so that Jenson doesn't send me another chain thinking it's the chain that is out of tolerance.

What do you guys think:
1) chain is too narrow - meaning < 1/8"
2) chainring is too wide - meaning > 1/8"
3) combination of both

And, if it is the chainring that is too wide, should I just file it down or should I send it back?

And again, Jenson has been cool about it with trying to fix the problem, but I think the problem is either at SRAM or Sugino - maybe a bad batch.

Thanks for any inputs!

I know every chain ring I have ever used has been tapered up at the teeth it almost looks as though that chain ring never went through that process of the production. I say bad batch on sugino

Just send back the Sugino cranks or have a professional bike mechanic look at it, dumb ass. It's obvious you got your head up your ass, otherwise you'd be out biking by now.

Anonymous,

San Francisco

Hmmm, true - it does look like the teeth are the same width as the body of the ring.

get one of those super wide bmx chains.

There was another guy last week having the same exact problem. Was it here or another f/g forum? I can't remember...

Seems someone's torn BF a new a-hole. Goes by vtho.

Recently someone came on posting about a too thick Sugino ring. Send it back.

*OP from that thread said an LBS mech told him he thinks there's another thicker size for track in Japan. They did replace it free of charge though.

Roadfix, did that guy say it was the chain or the ring?

I'm not RF, but it was definitely the ring

Yep. Sounds like Sugino put out a bad batch of rings.

HAHAHA - vtho is my gay friend in San Fran (I'm straight) and he's just giving me a hard time. I guess he literally does tear new a-holes.

I guess I'm not the only one who ran into one of those rings.

Something is wrong with those chainrings. Long story short (read my thread above for more info): none of the mechanics here in Portland knew wtf was wrong with those chainrings. Unless you're running a motorcycle chain it ain't gonna fit.

bad batch of chainring, dam that sucks

Cool. Thanks all who've responded. I'll give Jenson.com a call tomorrow morning.