[Closed] Rear mech tension issue

First things first...

Did you shorten the new chain to the same length as the old one?

The chain has been shortened enough to keep the chain running on the smallest and biggest rings. I will say I'm not 100% certain that the chain is short enough- I have used the mech position on the big ring to guide the chain length- mech lower jockey wheel sitting at the 5 o clock position.

Picture might help. Chain length should* be determined by wrapping around the large chainring and largest sprocket, then add 2 links.

* (May not apply for full sussers which get longer under compression)

I had never heard that rule- that would put my chain at 74 links (42+30+2)? That seems miles too short to me.

I'll try to get a photo of it- I haven't had this problem on my hardtail but I do need to check what the rear mech position is on that as well.

no, tthew means just set up as usual, but miss the nech out, be in big chainring/biggest cassette sprocket, pull tight and add 2 full links. If on a full suss, let the air out of the shock and measure in the longest chain position.

What kind of mech?

Chain length is normally big-big+inner and outer link, sometimes 2 inner and outer. Campag is small-small and 8-15mm gap between the chain and chain return around jockey wheel. If its a full suss size the chain at the point of greatest chain growth.

Chain length is normally big-big+inner and outer link, sometimes 2 inner and outer. Campag is small-small and 8-15mm gap between the chain and chain return around jockey wheel

Obvious when you put it like that! 😁

Sounds like chain far to long to me as well

big/big plus 2.

https://goo.gl/images/i1yHCS

if you look at the pic for that gcn vid you can see how the chain is wrapped around the cogs but avoids the mech, or just watch the first two minutes of the vid

Most Shimano

Some shimano (road less than 28t?)

Sram

Campag