I have converted a slx crank set to 1 ring on the middle ring tabs. I also have a superstar dual chain guide with a slx gs RM.

When i’m riding at speed in the smallest cog the chain keeps jumping off, i have checked the chain length and it is the biggest cog + 1 link.

Please help

Dual ring guide and a single ring?

I assume from the brief description that’s your fault.

If you’re using one of THESE (only mention of dual or double I can find on any S* chain guides) with a single rings there’s nothing to stop the chain bouncing off the top which will drop your chain the fastest.

You want either one of THIS TYPE or THIS TYPE to act like a front mech and guide the chain onto the ring.

Or one of those fancy chain rings of course.

Hope that helps.

Gaz

The double guide is doing nothing for you. You need a proper top guide/bash+jumpstop/xx1-style ring.

Edit: or what ^he said.

I meant a guide that has a roller as well as a top guide, sorry for the confusion.

I cannot recommend a magic thick/thin chainring too highly. Mine is Works Components, others are available. I’ve sacked the chain device on my hardtail now after trying it out at fort william and all over the dh and enduro trails at innerleithen, it stays on even while crashing which is more than I could say for the old E13 guide ring even with a chainguide. It is properly gamechanging.

I had this issue and it was happening with two different rear wheels and cassettes. I knew that the cassettes and chain were not worn, chain was the right length too. It was resolved when I fitted a short cage mech, I think I was running a long before.

Cheers will try a thick thin chain ring to see if it helps

Post a picture of your setup, someone may be able to debug it without you having to go to the expense.

I can vouch for the Raceface thick/thin chainring, been down some proper bumpy trails with no chain jumping at all. Magic.