I bought a barely used KHS Montana Sport. I cleaned it up and made a few adjustments, and took it out for an asphalt spin. I noticed at times when I would coast, then the rear cassette or the cranks would just spin, some times for a half a crank, sometimes for up to 2 cranks before it seemed to "catch" again and i could pedal. If I didn't coast it didn't slip.
It actually seemed to get better after a little bit of riding. Tonight I took it out to the woods where it got much worse. It would catch sometimes quickly, sometimes spinning for 10 seconds before clunking then catching.
Where do I start the diagnosis? The rear or the bottom bracket? What do I look for, just something loose?
This bike has such few miles that the front tire still had a fringe of rubber down the center.
Thanks for any help you can give.