Acquired an old raleigh 'milk' racer recently and having problems with the gears. As my name suggests I'm a complete amateur and don't know where to start with the issue though very willing to learn how to fix it.

The problem is gear clicking when I change out of 3rd gear. 3rd gear is fine.. no clicking at all.. anything else and the clicking starts, with the feeling of friction (though this could be a placebo of having clicking gears).

Any ideas?

The gear set is sachs huret. However, I have a feeling the problem may be with the chain being too big rather than the gears.. not entirely sure however. How could I tell if this is the problem?

Cheers