Only a small job by the standards of many, but satisfying nonetheless. Sprint back on the road for £57 - the price of two used peg hangers plus overnight courier from Wales - and maybe 3 hours in the garage. Exhaust end can has a dent in it but I can live with that for now. Whilst I had the bodywork off, I noticed the coolant was a little below the MIN mark. I topped it up and then went out for a 20 minute blat. On my return, I noticed coolant on the chain garird and various parts of the frame. I was half expecting this because when I first go the bike (20 months ago) it would do this. On closer inspection, I can see that it is escaping from the filler cap on the expansion tank. The 'cap' is a rubber affair - it seems a good tight fit, but clearly once the pressure builds in the system, it is insufficient to stop it from blowing past. I guess I'll have to see about getting a new one.