Hi

I recently bought an old racing bike, a 10 gear 'Cyclops Sprint' (It also has a sticker with 23 on it) and after spending the cost of the bike in repairs and replacement parts I've managed to get it down to one problem .

When I ride the bike on the smallest of the Derailleur gears the pedals 'click' or jolt forward with a delightful metallic clanging sound, making riding rather unpleasant. As I shift through the larger rear gears, this jolting occurs less and less frequently, with the largest gear riding smoothly, with no more than a slight crunching sound. I have already taken the bike to the repair store, where they told me that the gears are fine and shift without problem. They said they'd clean it up and replace the gear cable and that should clear the problem up, but it hasn't.

I am an absolute novice when it comes to bikes, so any light you could shed on what could be causing this would be great.