I have an 08 450x, done over 100 hours, 50 hours since Ive owned it. I'm having trouble with an inlet valve. Couple months ago I checked the shim tappets & found one of the inlets was completely closed up. I was having allot of trouble with starting it. So I got them set spot on. Now only about 10hrs of riding later its very hard to start again. I tried just now to go for one last spin but the bastard wont start at all. I know the cause of this, the titanium inlet valves pulling & closing up the valve stem clearance. Ive also heard the go is to replace them with Stainless valves. So I went to the local Honda dealer yesterday & talked to the guy there & he said that rite now my only problem is pulled inlet valves but if I replace with stainless I might it cause damage/pounded valve seats. I should really get new valve seats to suit the SS valves too. What are your thoughts on that? Those of you who have simply replaced your OEM inlet valves with SS valves, have you had any more future trouble? Should I just order a pair of SS inlets & a head gasket & do it myself? Or should I send it to a specialist in Australia & get it ported & polished & get them to replace the valves with what ever they recommend? Havnt found anyone yet, gona a look in a bike magazine for cylinder head work adverts. Anyone in Australia recommend where I should get the head work done? My experience: Dad's a mechanic & I'm a Machinist/fitter of 7 years & ex-cylinder head re-conditioner, have a workshop manual, fully capable of doing my myself. But may be worth getting the Pro's to do it? Thought? Cheers, Paul.