Sorry for treading on this subject. "Cambio" means "change" too...
Well, now back to the subject. When Ignacio asked about performance, Mike Rieck inmediately came to mind. But as long as he only want a valve work, I'm positive the cost of sending the head and the postage back from the US will easily exceed the cost of the labour of any decent machinist.
Ignacio, I took my CB350 head to a local shop near Madrid. They charged 30 euro per each cylinder lapped, 3 euro per each valve seat cut, and 4 euro pear each valve grinding. You can buy springs and valves from spanish Honda, I buy a lot of things from them, but be ready to pay the price. Valves are pretty much standard, and many pistons and rings are too. Many machinists have catalogs from different manufacturers; as long as the piston, valves and rings dimensions fit, you are good to go.
Look in the yellow pages for "talleres de rectificados". Once you go there, have a look around. If they don't have a counter, are located in a suburban area, and have lots of multi-cylinder heads around, that's the place to drop your engine head. The shop I took the cylinders and head even welded a broken fin. Not a brilliant job but enough for me.
Raul
