I did the 12k service on my bike at the weekend. I had a Triumph trained mechanic come around to show me how to check the valve clearances. Now I've done it once I'm happy to do it again as it's not as scary as it seems. One out of 12 was 1 thou out of tollerance. Not worth changing the shim for that. I saved myself a few quid there as it had new chain, air filter, plugs, oil, oil filter and brake pads all round. The parts alone cost me £200 but I've saved over £200 on labour although I did bung the mech 20 quid.