After a few years with no use, I've started riding my bike again.
Replaced all the cogs front and back, the chain is quite new (only ridden once or twice on older cogs).
Adjusted stuff as best I can, but chain seems to skip, especially when it's on the smaller of the back cogs.
Any ideas what this is - adjustment? need new chain?
I used to know all this but I seem to have forgotten my most basic bicycle maintenance skills.