2009 yz450 valve questions

i have a 09 that is nearing 100 hours and the valves have been shimmed twice so i think its time to replace them. So here is the questions do i get s/s kibblewhite valves or the oem titanium valves? i would like these to last another 100 hours i am going to be on this bike probably for another 6 months.

no body has a opinion on this subject?

Most people say to go with the OEM titanium. The SS will probably last longer but will rev slightly slower because of the added weight of the SS over titanium. I'm rebuilding my head (and hopefully selling the bike to get something newer) with the OEM titanium. Don't know if this helps much. Just my $.02:thumbsup:

The SS ... will rev slightly slower because of the added weight of the SS over titanium.

You will neither notice nor be able to measure any performance loss with stainless. However, SS valves do need heavier springs, and in the case of the Kibblewhites, their spring kit is so expensive that it brings the price of the whole set up up to the same level as the OEM stuff.

Also, there's objective proof that I know of that the SS valves will outlast OEM Ti in a YZF. It's sort of a toss up, really. If you can get valve springs from another source without having to pay for KW's Titanium spring retainers, it would be much less expensive to go with SS valves. Before you ask, the springs for the 400/426 with SS valves are the wrong physical dimensions to fit the 450 head.

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