My 1WG keeps going down on a cylinder, but the problem seems to go away after tweaking the HT lead a bit. I'm going to try cutting the lead back and screwing the end back on. If this doesn't work where's the best place to get new plug caps? Or am i best off just going for new leads?

I think your doing exactly the right thing and it should sort out the problem.

If you still think it's a cap then change the suspect one with a known good one. If you replace them then try to get a NGK part number or buy them off ebay (I'd use FZR600 or Thundercat ones), but Halfords also stock caps. I'm not sure if you can replace just the leads, maybe you need a replacement used coil

on mine the lead pulled out (with a little persuasion!) and pushed back in onto a 'pin' for want of a better word to make the connection. just make sure the lead is the right diameter, ive got a set of coils i think if you need any.

Ok thanks. I'll let you know how i get on