bought a 04 wr450 and have the stock valves for sale

took delivery of the bike this week and took it to my performance shop to get the heads done before i started it. i now have the titanium valves and the stock springs and valve guides for sale. they still have the colour codings on them from the factory.

i also have the stock top triple clamps, stock alloy bars, and stock exhaust up for sale as well

Wow, I didnt think there was a better valve then the factory titanuims :cry:

anyone know if i can put them in my 99 400? :cry:

the factory items are very good yes, but i am putting in some stainless valves with titanium springs in place of the stockers.

you would have to check the dimensions of the valves to find out if they'll fit your bike. that being said and not being qualified i'd imagine that they could be cut to suit with the correct tooling

the factory items are very good yes, but i am putting in some stainless valves with titanium springs in place of the stockers.

just curious as to why? indy_wr450 has like 10,000 mi. on his,been adjusted only 3 times and just now are ready for a rebuild. mine have a 1,000 + mi. and are still at the same spec as when i checked em' after breakin! you didn't ride a CRF before did ya? :cry:

Stainless is actually kinda soft. I think these woudl wear fast, maybe not? Hey NC, what they need is some irridium valves! :cry:

My reasons for changing out the valves are a carry over from the valves in my WR250F pulling through after less than 1400k's (900 odd miles), and my mechanic Carl Batey (Cafe Racer in Bathurst, Australia), suggested it. If he can get an 2001 XR400 to double its original Hp at the rear wheel and keep the reliability intact then I think I'll trust him with my 450.

The combination of these reasons is why the work is being done and why i have the valves up for sale.

As for the stainless being soft as suggested by toyota_mdt_tech it depends what grade you are talking about, 304 grade (a2-70) has a tensile strength of 70000 psi and is one of the softer of the stainless steels used in industry. I would like to ask though with all due respect, what is it you are comparing it to in saying it is soft? the other side of the coin is that the harder the material the more brittle it is and hence more likely to shatter.

Oh and no i didn't ride a crf, ever, and i dont plan to anytime soon either.

the harder the material the more brittle it is and hence more likely to shatter.

bingo :cry:. but, has any one busted one becuase of this? i havnt heard of any.....

my question to engineers is given that ss is heavier than ti, would this effect performance?

Yes the s/s is heavier than the ti, but it isnt a great difference, and the kit the valves come in includes appropriately weighted valve springs to cope with the slight weight increase.

As far as the valves not shattering goes as simon points out, the comment was made in a general sense, albeit by someone who is not a metallurgist. The valves shattering is as yet unrecorded as far as i know, though still entirely within the realms of possibility.

Stainless is actually kinda soft. I think these woudl wear fast, maybe not? Hey NC, what they need is some irridium valves! :cry:

maybe ngk could make us some? :cry: your a regular wiseguy eh!!! :cry:

I think the stock Yamaha Ti valves are hard to beat. I cant see getting better perfomance or needing it. :excuseme:I think the WR250's have had pretty good luck with stock valves even though the riders tend to rev the engine higher then we do on the 450's. :cry:

its a reliability thing, just ask the editor of an Australian dirt bike magazine whose name i cant remember, i think it was Australasian Dirt Bike, who had to push a wr450 out of cape york when it failed mechanically, it was valve related. the other reason, is i can get the heads hi-flowed at the same time and only have it apart once

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