[mmckinlay]

I just bought a 2004 CRF450R (A little difficult to start when cold, push start works every time, however, when warm, not a problem); took it on a couple of rides and decided to check the valve clearances. Upon inspection I found the exhaust valves to be with in limitations but the intake valves are always open. I couldn’t even fit my smallest feeler gauge in there. I have been told by the local mechanic to go with SS valves, cut the seats and go on my way for 4000 miles without messing with anything(I'm skeptical). He also told me this is a very common problem and that Honda fixed it in the 06/07 model. I am an intermediate level rider who enjoys the desert and the mountains, not the track. I want to do the right thing but don’t want to spend a ton of money. I can do the work myself so labor is not the issue. I have been told that if I re-shim it the same problem is going to happen after a couple of rides. How could that possibly happen?

New Valves, TT or SS? New Head? Or, just new shims?

Opinions? Thanks

[JAWS]

Your mechanic is correct. The titanium valves have a coating that wears over time. When they begin to move, the end is near and the frequency of shimming accelerates quickly.

Go with the stainless if you can afford to. The Kibblewhites are what most are using for the 450r. You must buy their springs though and that about doubles the cost. Worth it in the long run, though. You can go with stockers if you want, but you will be doing this again sooner than the stainless ones.

Keep your filters clean, oiled and sealed for the most longevity in your valves.

Joe

[mmckinlay]

I don't understand how it expands so quickly? I willing to bet the bike has never been re-shimmed before. Would you say its safe to re-shim it for now and do the stainless in about 20-40 hours? The only thing I'm loosing is HP correct?What I am afraid of is doing any internal damage to the engine.
I suppose I could pull the shim out put it all back together, measure the distance, order the correct shim and see what the difference is.

Thanks,

[JAWS]

If it's never been shimmed before you can get away with it for a while depending on its condition. The danger comes from trying to make it last just that last little bit. You may get more than a few rides out of it in the beginning, but soon you will have to shim every ride.

Shim now if it's the first time and start saving your money, or order the parts and just wait.

Joe

[mmckinlay]

ok thanks, will do.