[Closed] Indexing or something else?

worn cassette

1 Check mech hanger.

2 Is cassette worn?

Edit: Damn you bruneep!😁

I did check the cassette but it looked fine. None of the shark fin shaped teeth. I have a spare 9 speed cassette which I will try out.

I did eyeball the hanger, didn't look bent or out of alignment, bike hasn't been crashed or dropped. If changing the cassette doesnt do anything I will change the hanger.

all our hangers were not straight

probably either cassette or hanger, I've also installed SRAM chain links upside down before, so worth glancing at that as well. (although I think this is something that only really effects 11-12 speed chains or those with single use links)

Worn cassette and chain - most likely...chain more so than cassette.

outside possibility but had something similar recently and freehub was loose (but not that obvious) because cones not tight enough...def got big knock jumps on small out back

most likely…chain more so than cassette.

Except he changed the chain! Cassette might not look worn, but might be worn enough to not mesh properly with a new chain. Could be your chainrings if not cassette, less of a chance if it skips in all three usually it's the middle one that wears fastest through most use.

Totally slipped my mind but before all this happened. One day all of a sudden my chain went all loose. Like it was too big. It had been fine for months. This is the old chain I'm talking about. Thinking what the hell I removed two links and the gear problem was still present. Removed the derailleur, looked ok, the spring was fine, compared it to another derailleur I had and it seemed fine. That's when I changed the derailleur and chain. I tried the limit screw, checked everything by searching similar threads but nothing seemed to work. In the small chain ring and the hardest gear the chain was actually touching the chainstay.

The derailleur is the only thing that takes up the chain tension, so that must have been knackered in some way. As you've replaced it, I think you can rule out that unless it's come to you broken.

Thinking about it, is the B screw badly adjusted so the top jockey wheel is miles away from the smaller sprockets? Could be there's not enough chain wrap, worth a try before the new cassette.

The freehub is tight. Changed wheelset so double checked.

Followed the videos, small gap between jockey wheel and smaller sprocket.

When you say the chain was loose, was that during freewheeling? If so it would point to the freewheel binding and dragging the cassette slightly, which would cause the chain to sag if not pedaling.

Similarly, if the slipping has a metallic pinging/cracking noise that could be the freehub pawls slipping.

Other than that, does sound like the classic new chain slipping on old cassette problem.

First thing I'd do is put the old chain back on, it's worn the same as your cassette. If it fixes the problem, run the drivetrain until it's knackered.

New bike day....

In the small chain ring and the hardest gear the chain was actually touching the chainstay.

need to get that thru my brain...don't think should happen...cross chaining was banned in our household just after we converted to natural gas so hard to picture...what happens big front with small back? ...seems to say to me need to check for bent hanger (if already ruled out I missed it)

A bit of an update.

I tried a different cassette and the problem is still present.

Have ordered a new hanger.

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