[Closed] New drive chain - chain length

Depends how much chain growth your particular bike produces.

12s in general is quite fussy about chain length/b screw

https://dansbikeblog.com/article/how-calculate-correct-chain-length-shimano-12-speed-drivetrain

This also depends which 12 speed drivetrain you’ve fitted. Shimano has one way of sizing detailed in their user guide, whilst Sram have a different way (on full suss it has to be sagged to the position where it has most chain growth).

Let the air out the shock and see what it’s like.

Let the air out the shock and see what it’s like.

Obvious advice is obvious.

Shimano 12s is definitely different, as above. With 10/11s I've always let air out of shock, fully compress, big/big, add two links. But the chain was far to long on the Mrs new bike. So went with the normal but uncompressed and it's fine (like the above link actually).

Slight variation on this theme - if i change from a 32T 12Sp Eagle chainring to a 30T chainring - How many links should i take out of the chain? 2 (1 wide/1 narrow) or 4?

Slight variation on this theme – if i change from a 32T 12Sp Eagle chainring to a 30T chainring – How many links should i take out of the chain? 2 (1 wide/1 narrow) or 4?

Well, you've gone from 16 teeth forward of the BB to 15. Everything else is staying the same, except a tiny angle change. I'd start with keeping it as it is. If it's too long then take out one pair of links.

@luket thanks - will give it a whirl

Drive train....

Slight variation on this theme – if i change from a 32T 12Sp Eagle chainring to a 30T chainring – How many links should i take out of the chain? 2 (1 wide/1 narrow) or 4?

I did just this last night on my wife’s bike. Using SRAM’s wrap around and overlap by 2 method I took out a complete link (one narrow, one wide). I didn’t try it before shortening so don’t know if it would have been OK or not.