rumrunn6

rear der doesn't like staying in 2nd smallest cog. I thought I had chain hop requiring chain and freewheel but The condition did not go away after changing both.

when I'm in the 2nd smallest cog it wants to jump and then does jump into the smallest cog. so I've been staying away that cog and just using the smallest one and then the next larger one after #2

suggestions please

bentonville

have you adjusted cable tension?

rumrunn6

to some degree, I think so. when the chain and freewheel were changed the shop also replaced the rear der cable.

bentonville

Did they replace the housing as well?
Was it taken to the shop for this problem?

rumrunn6

yes it was taken to the shop for this issue. I'm not sure about the housing, it may be the original housing because I don't remember seeing "housing" on the receipt.

fietsbob

there is an eagerness of the new tooth profiles to shift, whereas the older cogs with tall teeth and no ramps
in the faces, tend to stay put .. it could be a side effect of the indexing mech..

Shimano, note, has lateral float in the guide pulley , perhaps there is a combination of the parts of the indexing scheme,
adjustments, fine and , like dropout alignment, cable clamp slip and the return spring in the rear derailleur, all working against you..

bentonville

would try adjusting tension first. turn the der barrel CC 1/4 turns until it shifts up to the second smallest and stays(testing after each turn). Also make sure it will still drop into smallest ok without any noise. it is possible cable stretch is mimicking the original problem but then again it could be something else that was missed. Once it it shifting properly test all of the gears.