Hi.
I picked up a very cheap bike, Gary Fisher, to get me to work.
It rides OK except for the 3 smallest rear cogs where it seems to jump. I have cleaned everything up and re-lubed, checked the chain length and it seems fine. The cassette all looks the same no difference in the teeth large to small. The derailleur seems straight but obviously i'm a newbie so cant be sure, I have attached a pic.
It doesn't do it when on the bike stand, only when under load. Seems to get then jump then go and then jump again. Shift into 4th smallest and it stops.
Can anyone offer any ideas on the jumping? its very annoying.
by dorkingwed
2 Comments
Either a worn chain or bad indexing.
https://youtu.be/UkZxPIZ1ngY
Is the cassette new? If not the three smallest sprockets may be worn out. This is likely to be particularly bad if you’re using a worn cassette with a new chain.