Derailleur setup question (skips )

[metalMTB]

My derailleur is set up perfectly. Both tension and limit screws. Chain is correct length and everything and the derailleur hanger is straight up and down. However if I look closely it looks like the hanger is slightly (can't tell if it's the derailleur or hanger because its so small) bent outwards. It's hard to explain but it kinda looks like this from above / . Except its not that bent. Would this explain skipping in 4th and 5th gear?

[mcoomer]

If the derailleur or hanger is bent it can affect the ability of the chain to roll on the cassette. If you have access to a derailleur alignment guage I would check it and if the hanger is bent slightly you can probably bring that back to true.

The last time I had trouble with the chain skipping it was simply that the chain needed a good cleaning and lube. If there is anything that causes the chain to kink that can cause the chain to jump as well.

Hope this helps,
Mike

[oldfart]

Assuming all the parts are clean and not worn too much, I would suspect a bent tooth on the cassette. It might be one link is damaged and it only catches in those two gears. If it were a stiff link it should skip in any gear. A slightly bent hanger shouldn't cause it to skip in only two cogs. There is enough play in most derailleurs to make a slight bend irrelevant. It must be something with those two cogs and how the chain meshes with them.

[metalMTB]

Yep, it was stiff link. I didn't expect it since I was riding on it for a couple weeks straight and i didn't touch my chain. Oh well. Works great now.