Hi,

I bought a second-hand bike recently (apparently not ridden much, a Ridgeback Comet) but there is an issue with the gears, or at least I think there is, because I haven't ridden a bike since I was a child and am not what normal is.

The issue is, when I change up a gear the pedals will always jerk forwards as the gear changes. I only use the top four gears and this is quite disconcerting when going at speed on a busy road.

I got the rear wheel off the ground and had a look at the bike.

I can see that when I change up a gear, the chain comes off the rear cog until the chain is still hooked on the old gear at the top of the cog, and then drops onto the higher gear, and its then that the pedals jerk forwards.

Appreciate any help for a beginner.

Thanks.