Chain skipping??

FST4RD

Senior Retro Guru
Hey all, been riding my bike to death and realised the other day when my chain was skipping it was worn out.
So got sent a voucher from CRC and decided to use it.
Bought a new Sram 991 chain, Shimano XT cassette and Blackspire 22t and 34t front rings.
Installed the whole lot and also cleaned up the rear mech (XT Shadow in great condition) and put new KCNC jockey wheels on.

Went out riding today, shifting was flawless and rode very smooth. However when under power the chain skipped a couple times...
The B screw was wound out so the top jockey wheel is as close to the cassette as it can be (not touching the cassette however).
I didn't lube the chain as it comes with that waxy lube from factory. Can this cause it?
Any ideas? Will try and get some photo's up soon.
 
No the freehub does skip every now and then, although that makes a different noise, and the freehub only skips when I stop pedalling and coast and then put the power down again. (It's a Deore hub... and I'm 120kg powerhouse, don't go well together! :LOL: )

I might try and lube the chain up properly and see if that makes a difference.
 
You've changed a lot there:

Are the jockeys are binding or too tight and catching the chain springing the derailleur back before losing tension before it engages again.

You've cleaned the mech, pivots lubed OK?

Is the mech cage twisted or not inline?

Can you tell when it slips if the chain is trying to jump up or down a sprocket, or chain losing tension and slipping?

I think the factory chain lube is good stuff, it never seems very loose on the links but I leave it on.
 
Jockeys spin freely, I pulled the derailuer off the bike, cleaned, lubed and installed the jocky wheels. Everything was spinning freely.
My mate has a parktool aligner thing for the rear mech and used it on my bike just a couple days ago.
Bike back pedals freely as well.
Gears are fine as far as alignment and adjustment are concerned.
I think it's more like skipping under power rather then dodgy gear tuning.

I'll get some photo's up in a sec.
 
Here pics of the drive train. Excuse the dirty bike, just got back from an hour out on the track.
So can anyone see anything wrong with the setup?
 

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I think the waxy substance is a protective coating rather than a lubricant, so I always oil a new chain now, but I did find some problems with new chains previously.

As you say you have 'realised' that your old chain was worn out, it makes me wonder how you realised. In many cases, people realise that they need a new chain quite a long time after the chain should have been replaced. By that time, one or more of the rings, sprockets and/or jockey wheels may have been damaged by the chain. So there are still problems with a new chain.

If on the other hand, you realised when you measured the chain, which you do regularly, and it was looking more like an eighth stretched than a sixteenth, then it's much less likely that you've damaged the rings, sprockets and/or jockey wheels.
 
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