Chain jumps on smallest cog.

chips_44

Hi guys,

I had some difficulties converting my 3by setup to a 1by, managed to solve most of them, but the chain still jumps on the smallest cog. I have a new crankset, chain and cassette (4-500km), so it should not be worn. Anyway, I just upload a pic of my smallest cog. 2 more to judge the length of my chain, maybe i could shorten it a little bit. I am out of ideas.

keef66

Yes, you could shorten the chain a bit. Have you checked the chain for wear using a tool or by measuring it?
What exactly do you mean by jumping? Does the chain skip forward when you apply power to the pedals? Does it happen only when pedalling or can you see it when you turn the pedals by hand?

Is it possible you've fitted a 12t lockring with an 11t cassette? That can foul the chain preventing it from fully engaging the smallest sprocket

chips_44

Yes, that tool should fall in entirely, right? It does not.

Yes, I meant that and only skips when I apply power to the pedals.
The lockring should be ok, came with the cassette.

keef66

chips_44 wrote:

Yes, that tool should fall in entirely, right? It does not.

Yes, I meant that and only skips when I apply power to the pedals.
The lockring should be ok, came with the cassette.

Well in that case I'm stumped too. The symptoms sound like what happens when a new chain is fitted to a worn cassette, but you say the whole drivetrain is fairly new...

milemuncher1

Try increasing the angle of dangle by turning the ‘B’ screw on the rear mech clockwise, when on the smallest sprocket. Be careful that it doesn’t choke at the largest sprocket though.

02gf74

Stating the obvious but you have adjusted the limit screws, and checked the chain is centred on the smallest sprocket.

Generally 1x systems use a clutch rear mech, the one fitted does not appear to be one, if it is, then make sure that the clutch lever is in the on position.