Rubbing chain
 

As it says really, after adjusting my chain yesterday I have obviously got something wrong!

There is a metal plate on a bracket behind the rear mounting hole for the chain guard. The chain is rubbing against the plate. I now have brightly polished rivit heads.

When I adjusted the chain I tried to ensure that I moved the wheel back evenly both sides, but I must have failed!

So, experts of the org, how do I put it right?

Many Thanks.