Stainless Steel valves Vs. Titanium valves

[bluchevon20s]

Ive a hard time decide between stainless steel valves and titanium valves. i know if i get the stainless steel ill have to get springs. which adds to the prices. but titaniums are so much higher. give me your opinion?

[cmepasu]

stay with ti valves. the yfz is designed with these valves for a reason, they are way lighter and help the engine rev faster. stainless valves are good if your driving a sunday street cruiser and still want to have some fun, but if your looking for seroius performance then TI all the way.

[newatnothing]

Originally Posted by cmepasu

stay with ti valves. the yfz is designed with these valves for a reason, they are way lighter and help the engine rev faster. stainless valves are good if your driving a sunday street cruiser and still want to have some fun, but if your looking for seroius performance then TI all the way.

X2^^^Stainless will work just fine but i hear it drop the compression stick with ti

[Narmasil]

If you run with Stainless it will give more stress to the top when high revving. I would rather do it once and do it right...... Titanium :)

[nickmell]

Stainless valves will not lower compressioN. But you may notice a littlEless preformance Since they are heavier.stainless. Valves will last longer than tI valves thoUgh.

[rednbluerider]

Are you talking about oversized valves or standard sizes?

[kb motorsports]

I'd go with Ti Factory valves for reliability and performance, and if you wanted to save a little and go Kibble White Stainless Steel Valves. Over half of the people who buy kibble white valves off kbmatv.com does not buy the spring kit. I personally called a couple of those guys myself a few months later, and asked them which springs they decided to run and they all told me the original factory springs.

[nickmell]

I have read if you use stock springs with stainless valves, the valves will float at high rpm. I have never tryed it though.

[cmepasu]

i definetly wouldnt chance it, id be buying springs to go with ss valves, but like i said stay with ti valves regardless if they are standard or oversized valves

[bluchevon20s]

Im going to go with Ti

[ridehardyfz]

titanium less life, lighter, rev faster. stainless rev slower, longer life. completely opinion, also depends what kinda riding you do.

[cantcatchme3288]

hey guys i know this is a little older of a thread but instead of starting another i figured id just bring this one back.... here is my ? other then weight why is TI so much better then SS. i have herd that you cant rev SS as high or you will bend a valve or beat the seats right out but i cant seem to wrap my head around why. her is my situation, i have a full 1+ head with KBW SS valves and KBW dual springs. i was told to bring the REV down to save the valves and seats. after talkin to my dad (drag racer 700HP 9.70 car/mechanic) he is running SS valves in the car and it turns 8500RPMs with more compression and he doesent see a prob other then SS has a different heat disipation rate then alum, and that they are heavier. but with good springs would any of you be scared to run the bike on the stock limiter? i dont need more then stock as i dont drag race. just mx. i just want to put my bike in any danger but dont see spending the money for TI valves when i have 5 perfectly good valves in the head. also is there something i am missing?????

[lbyfz450]

I wouldent go replacing them if there fine.
And also the power is not at the limiter, when your riding you wont hold the throttle pinned anyway so I would just run stock limiter, you have the springs to controll it, so whatever.
Ti are lighter, making less wear on parts, and the ability to rev higher then ss, but I don't Beleive ss has hit it's limits on the stock Cdi..
Run your ss and don't worry about it.

[nickmell]

Most of what you heard bad about stainless not being able to rev as high probably came from people who used the stock springs. Ss valves require heavier springs to keep them from floating at high rpm.

[lbyfz450]

Very true.
But going even higher then that, ti will be able to rev higher, like gsxr 1000 wouldent be able to rev to 16,000 on ss, well maybe but the limit is lower on ss..

[cubanaso]

idk but ive heard from different builders that Ti is lighter however it makes only make a little more power and rev a little faster but wear out faster. personally im running KW SS +1 valves with HD springs.

[upon2passingyou]

The ones who are saying SS last longer are contradicting themselves when speaking in high rpm applications. The Ti valves will last much longer in these 450 engines than stainless. Maybe in an engine that at most sees 7500 rpms, stainless might edge out titanium. But titanium is some tough stuff regardless. And the reason your dad doesnt have a problem running SS in an 8500 rpm v8 is because of just that, its only 8500 rpm's at 2 valves per cylinder. Were talkin engines that are always usually between 9-11k. Besides, why would anyone want to give up the already proven stock valvetrain in the yfz? I have a 2004 wr450 head on my bike right now with the stock valvetrain and shims in it. It hasnt needed a valve adjustment since I built this motor in 2007. Once you get the wr crank in there and the oil modification done, and you run good oil not the cheapy stuff; you got the most reliable 450 engine available!

[cantcatchme3288]

ok well the head is at the builders now as cause i wanted it reported and polished and wanted to try something different but i will not disclose the builders name until i get the head back anyway the info i got was from him and i take his word as the BEST word in the business and i am not contridicting what he is say i just wanted to understand it myself. but he had asked me to bring the limiter down on the bike from stock to 10,000 so there wouldnt be a high chance of problems and thats the reasoning for my questions. will stock be ok for an mx bike ( panic revs and WOT shifting) TIA guys

[climb-101]

Originally Posted by nickmell

Stainless valves will not lower compressioN. But you may notice a littlEless preformance Since they are heavier.stainless. Valves will last longer than tI valves thoUgh.

the stainless will lower the compression a little since they are dished inorder to loose some weight off the valves compared to some of the Ti ones that are flat faced on the falve

[Narmasil]

Originally Posted by cantcatchme3288

ok well the head is at the builders now as cause i wanted it reported and polished and wanted to try something different but i will not disclose the builders name until i get the head back anyway the info i got was from him and i take his word as the BEST word in the business and i am not contridicting what he is say i just wanted to understand it myself. but he had asked me to bring the limiter down on the bike from stock to 10,000 so there wouldnt be a high chance of problems and thats the reasoning for my questions. will stock be ok for an mx bike ( panic revs and WOT shifting) TIA guys

With right gearing etc you dont need to ever go to the rev limiter. The bike has noticeble much more pull around 8-9000 rpm than 10.000+. The thing i would like the high rev limiter to be as a bit of safe thing in case you take a dive in a jump, the few times it happens i kick up the shifter a notch and panic rev. Only works on big jumps ofc.
Edit: The most common wrong things people do wrong when accelerating (for holeshots etc) is that they shift too late, thinking high rev = high power. But thats wrong :)

For MX racing Stock valves works fine unless you go A-Class Pro riding


Would be fun to see how long a bike lasted ON the rev limiter until it breaks. I know some guys did a test on a Honda 450 4 stroker some years ago. After 40 minutes!!! they couldnt be arsed to wait so they bashed it with a big sledge