I’ve recently replaced the drivetrain on my bike. Set up is sunrace mx3 11-42, superstar oval 32. New chain and new jockey wheels. All components replaced at the same time. Long cage mech and triple cranks with one spacer moved from drive side to non drive side, so with the offset chainring it’s quite a long way inboard
The chain was not shortened at all and could probably cope with an extra couple of links without being too long.
In the 42 there is a clicking which is caused by the chain riding up and off the bottom jockey wheel as if it’s being pulled across too much. Doesn’t happen in any other gear.
I’m not sure if this is par for the course, and will improve as the chainring wears in, as it does seem to want to hold onto the chain as it comes off the bottom.
Or should I just put some extra links in the chain?
Anyone else had this?
It’s a fs vpp bike so a bit of chain growth but that doesn’t seem to be affecting it.

Try adding a power link?

Could be a bent derailleur / derailleur hanger perhaps, had this on a bike I was working on a few weeks ago.

Bent hanger, I had the same prob on my mates bike

Mmm. Mech is quite old. Might be goosed.

Another vote for alignment issues, or pivot slop.

Update:
Fixed by adding 1 link and a quick link so 2 whole links to the chain.
Probably because it’s a long cage mech. Just slightly too tight in biggest sprocket.