Chain / chainring i...
 

[Closed] Chain / chainring incompatibility - different pitches?

Posts: 6934
Full Member
Topic starter
 

Ordered a new NW 30T chainring for my kid's bike and it doesn't mesh with the 7 speed chain. It looks like the teeth spacing is wrong, like the chain pitch is v slightly different. Is this the case between 7 and say 9 or 10 speed?
The previous chainring I just ordered randomly off amazon and it fits fine, so wondering if there's some obvious compatibility issue I've missed with the new one, or if it's something else.


 
Posted : 30/05/2017 9:43 pm
Posts: 57
Free Member
 

It's not the pitch, it's the width. The fat teeth are probably too big to go into the gaps for a narrow chain - unless you've got the NW out of sync


 
Posted : 30/05/2017 9:48 pm
Posts: 41395
Free Member
 

7 speed chain wider than 9/10/11.

Wear?


 
Posted : 30/05/2017 10:53 pm
Posts: 6934
Full Member
Topic starter
 

Thks for the replies, I Had another go at this today and it's a bit of a puzzler. Taking the chainring on its own and wrapping the chain round is a perfect mesh. On the bike though, it isn't, Doesn't mesh and jumps up (looks like the pitch is wrong, hence the initial question) . The tension in the chain must be causing problems.
The puzzling thing is the other 32 chainring is fine on the bike. So it's not like there's something dramatically wrong with the chain line or anything like that.

Any ideas on what might be going wrong?


 
Posted : 03/06/2017 5:43 pm
 beej
Posts: 4195
Full Member
 

How old is the chain?

If you are just putting on a new chainring with an old chain, chances are the old chain will have stretched. Have you got a chain gauge?

Try a new chain too.

That'll then skip on the rear cassette (probably) as that will have worn too. So you'll need a new cassette too.


 
Posted : 03/06/2017 5:48 pm
Posts: 57
Free Member
 

You haven't joined the chain with a half-link, have you? That would stop meshing after a complete circuit of the chain


 
Posted : 03/06/2017 5:50 pm
Posts: 6934
Full Member
Topic starter
 

The chain is more or less new, just a couple of rides. Shouldn't be a problem, although I agree it sounds like it is.


 
Posted : 03/06/2017 5:54 pm
Posts: 0
Free Member
 

Is it a superstar ring by anychance?

I fitted one the other day and have had the same issues with a 9 speed chain on it.


 
Posted : 03/06/2017 6:27 pm
Posts: 7998
Full Member
 

I had a 32tooth superstar that seemed to need bedding in. Took about 75miles or so of riding for it to settle down and go quiet and smooth (from brand new also with brand new 10spd chain and cassette).

My 34t hope retainer ring is similarly grumpy (newish setup again).

Not sure if that helps or not.


 
Posted : 03/06/2017 11:04 pm