Chain jumps @ high power

[kfjatek]

Put the bike back together after the PL trip and went for a quick ride yesterday. Purrrrrs like a kitten, except for hills, where I need to put more power to the pedal - that's when I feel/hear the chain "jumping" every couple of seconds.

- Doesn't seem to be gear misalignment, as the shifters work fine and switch gears smoothly, plus the chain doesn't jump from gear to gear, just over the
- I don't *think* it's a stiff chain link, as that would manifest itself all the time I think, rather than just on the hills. Will check just in case, but this shouldn't be the case
- Shouldn't really be chain wear, as the chain has less than 1k kms on it. Plus, it wasn't doing it in Poland, which would suggest I screwed something up when I was putting the bike together after the journey back

Anyone's seen anything similar in the past? Any thoughts as to what could be causing it?

[Jack Hughes]

Not really convinced that I get what you mean by "jumping". Is it the derailleur "sticking", and creating a loose chain?

Only up hill? Only in a specific gear (one of the lower ones?). Only with chain on smallest ring?

Can you reproduce it on turbo?

[kfjatek]

Difficult to explain. Feels a bit like the chain was losing grip on the sprockets for a split second, then goes back to normal. Haven't put it on the turbo yet to check if I can reproduce it - will do today/tomorrow and report back.

I was doing some power-ups during the ride yesterday (20s max acceleration from low speed on high gear) and it jumped then a couple of times, plus every time I was in relatively heavy gear when going uphill - but disappeared when I switched down and/or at my standard cruise-speed gearing.

Odd.

[Jack Hughes]

Wheel slip?

[kfjatek]

Wheel slip?

Joker.

[Worrying Will]

Daft question is it the same sprocket and chain.

It sounds like a new chain old sprocket issue I had whe n I replaced the chain

Could be complety wrong

written using my bestist willglish

[Jellybaby]

Sounds to me like you've put the chain on backwards

[moose]

Free-wheel not loose, might have vibrated loose at little and then put under power it's slipping a bit??...now what that be tightening it from already being loose in which case the problem will resolve itself or is the at loosing it so eventually the free-wheel will drop off, I guess it would best if it's not that then

[kfjatek]

Sounds to me like you've put the chain on backwards

I actually might have. Or rather inside out, so what the sprockets are getting is what used to be the outer side of the chain before..

[Jellybaby]

I was rather taking the piss. If it's had less than 1k kms on it then it's not going to be that. I'd hazard a guess that you've maybe nudged the derailleur ever so slightly, or the cassette being ever so slightly loose. Is it happening on all the cogs on the back, or just a couple?