Originally Posted by
wagonfanatic
Occasionally, especially when peddling hard, the chain pops into another gear. Also, the bike doesn't always shift when I change gears. This could be an issue with the limits screws/ derailleur, but it was highlighted after I installed a new chain.
It's not your limit screws, it's the barrel adjuster. Check out adjusting rear derailers on Park Tool's website.
Another possibility is you're describing it wrong, and the chain is jumping over the cogs under load, staying in the same gear. If this is the case, your cogs are too worn for the new chain.