ghost shifting

[DebW]

Quite often you'll get more skipping with a new chain and old cassette. We'll typically replace the chain, then ride the bike to check for skipping under load, and replace the cassette if necessary.

[aicabsolut]

Quite often you'll get more skipping with a new chain and old cassette. We'll typically replace the chain, then ride the bike to check for skipping under load, and replace the cassette if necessary.

Yeah, if it's shifting fine and then you run into problems under load, it's likely your cassette. You might also want to take some WD40 and really lube up where the cables run underneath your bottom bracket as well as inside your shifters. That ought to get rid of any unnecessary friction on the cables that could cause the autoshift to occur when the frame flexes. You might also want to get the shop to check your rear derailleur and derailleur hangar. Make sure the hangar isn't bent. Finally, if you *still* have problems, make sure there isn't a lot of lateral play in the derailleur indicating that it's getting worn out and needs overhauled or replaced.