Wallonthefloor

When I am pedaling my hybrid with a lot of torque no matter what gear I'm in whether it is climbing a hill or pedaling down one in the hardest gear, whenever I go over a rough bumpy surface my chain makes a very instant "ping" noise. It does not fall off the gear and skip terribly, it is like one quick and instant skip that it very consistent when applying force to the pedals and riding over some bumps.

I did just get a brand new drivetrain (new cassette and chain) at 2 different bike shops. At the first shop when I got a new chain the mechanic said that my derailleur hanger needed adjusted so he also fixed that. On a different day I went to another lbs to get a cassette because I realized mine was definitely at the end of its life and the mechanic changed it but after it was put on it had too much play. He immediately noticed, took it off and said that it needed a spacer. I told him that when I bought my wheels from the other shop that they told me never to forget the spacer because my wheels are 8/10 speed compatible so I would need it. He did not find the exact spacer that it came with but said he had a box full of them and that they are all the same so he put one on significantly reducing the looseness of the cassette. I have no idea whats going on with my bike, it shifts fine, I just don't feel the stability anymore while pedaling over any surprise terrain changes.

Wheels: Shimano Wh RS-11
Cassette: 8 Speed Shimano
Chain: KMC
Bike: Giant FCR3 (aluminum)

Edit: I forgot the bicycle mechanic forums could help!

pressed001

This only occurs over rough surfaces? If so, sounds like cassette play. If you have a shimano wheelset, utilizing the proper spacer, your cassette should have ZERO play. Please let me know exactly when you hear the sound and when it skips.

In the past I had purchased a new chain for my wife's bike. I found out quickly that we also needed to swap out the cassette because it would "skip" every so often. But this happened over rough and smooth surfaces alike. And you have a new chain and cassette.

Also, I had bad cassette play once. It made a plinking sound that was pretty annoying. However, it never skipped.

There are a few possibilities here but they all lie within the chain/cassette/freehub area.