Hey guys! I recently was able to get the bike back from the owner, to take a look at what may be happening with the chain skipping.
I put the bike on the trainer, and had the gf pedal it to see what was happening.
My opinion, is that the two smallest cogs on the rear are worn, and causing the chain to slip.
So, Ive decided that the whole "freewheel" needs to be replaced. Id love you guys opinion on what I should replace it with, and where to get it. Id also like to hear opinions on if Im correct in my deducing what the actual issue is, if anyone has one.
The other gears all drive fine, it only happens in the smallest two, and under a "heavier" load. A light pedaling will not result in any slipping. Under a heavier load, one can see the chain sort of bunch up, and let a small amount of slack sort of slip at once, causing the slipping feeling.