Chain hop

First thought is a worn chain or rear cassette. Have they been replaced recently? Has one but not the other been replaced?

I'd like to think it's a wear problem. I don't ride enough. The bike may have 70 hours of mtn bike riding in it - max. The reverse pedal chain movement is very strange - the chain is angled so much from the front to the rear that it makes sense that it would skip. It could be the chain has become less flexible. I keep it clean and lubed.

Duckwah said:

First thought is a worn chain or rear cassette. Have they been replaced recently? Has one but not the other been replaced?

hmsolomon said:

The reverse pedal chain movement is very strange - the chain is angled so much from the front to the rear that it makes sense that it would skip.

So why not shift to a gear combination that lessens the angle?

Go here sheldonbrown.comgear theory.htmlOpen ↗ and be sure to read the section titled: Chainline and Criss-Cross Gears.

Also, the only time you should pedal in reverse is when you are applying lube to your chain.

I've read that Sheldon Brown piece. This nagging problem happens in the mid front chain ring and 3rd gear in the rear - middle to middle. It skips under load and when I do back pedal, as when remounting and positioning the pedals for a hill. It slides down several gears, just as the line of the chain from rear to front would suggest.

I have another bike with similar gearing and it will not hop gears when backpedalng. I did wreck on the last ride when this problem started. So the bike may have a bent rear deraler hanger! I'll check tonight.

Thanks for the ideas.

Scotty_Dog said:

So why not shift to a gear combination that lessens the angle?

Go here sheldonbrown.comgear theory.htmlOpen ↗ and be sure to read the section titled: Chainline and Criss-Cross Gears.

Also, the only time you should pedal in reverse is when you are applying lube to your chain.

It turns out the hop was due to the downward angle of the bike in my stand - front crank way below rear cog. When level, a minor rear derailler adjustment - so that the shift moves the chain quickly and just shy of an overshift - cleaned up the entire problem.