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yz250f replacement valves

By avoidthedog,
in WR250F/YZ250F/YZ250FX

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avoidthedog

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hi i have a 2002 yz250f and im looking to replace the valves and springs soon. what company should i go with for a cheap price and the best reliability. (without sacrifising performance). im not in it to beef up my hp, just to get new valves that will last a long time

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Grand Master

642MX

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hi i have a 2002 yz250f and im looking to replace the valves and springs soon. what company should i go with for a cheap price and the best reliability. (without sacrifising performance). im not in it to beef up my hp, just to get new valves that will last a long time

OEM valves/springs are as durable as anything. Be sure to have your seats touched up before you replace the valves. Also, make sure to install new valve seals. ?

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grungle

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I went with Stainless Steel valves and I'm VERY happy with how it's gone.

I got 11,000km out of the standard valves on my '03 WR - and I was pretty happy with that. I would have been happy to put them in again if it wasn't for the string of failures the '06 YZF's and CRF's had at the time of my rebuild.

Just for something different I put in the Stainless valves and uprated springs (from the TT store - Kibblewhite). I've done about 6,000 on them so far and haven't shimmed them since I put them in. It revs just as hard as it did before the rebuild. I can't see any downside so far, and they're cheaper than the titanium valves.

I've since done another '01 WR250F with stainless valves and that's still going strong as well. In my opinion (by looking at the composition of the valves, the hardening techniques and their failure modes) the SS valves *should* be more reliable than the Ti.

Just something to think about.?

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ButchWR250F

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I went with Stainless Steel valves and I'm VERY happy with how it's gone.

I got 11,000km out of the standard valves on my '03 WR - and I was pretty happy with that. I would have been happy to put them in again if it wasn't for the string of failures the '06 YZF's and CRF's had at the time of my rebuild.

Just for something different I put in the Stainless valves and uprated springs (from the TT store - Kibblewhite). I've done about 6,000 on them so far and haven't shimmed them since I put them in. It revs just as hard as it did before the rebuild. I can't see any downside so far, and they're cheaper than the titanium valves.

I've since done another '01 WR250F with stainless valves and that's still going strong as well. In my opinion (by looking at the composition of the valves, the hardening techniques and their failure modes) the SS valves *should* be more reliable than the Ti.

Just something to think about.?

Check your cam chain. The OEM cam chain is marginal at best with the lighter Ti vlaves & the lightweight springs. The kibblewhite valves are a little heaver than the stock ones, but the valve springs are MUCH heavier than the OEM ones. This puts added strain on an already weak cam chain. Once the cam chain stretches it will mess up the timing gear on the crankshaft. Once that gear is messed up, it's new crank time.

Remove the cover bolt over the cam chain tensioner & screw the tensioner in until it's all the way in & count the turns. If you turn it more than 2 1/2 turns, you cam chain is worn out.

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grungle

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Check your cam chain. The OEM cam chain is marginal at best with the lighter Ti vlaves & the lightweight springs. The kibblewhite valves are a little heaver than the stock ones, but the valve springs are MUCH heavier than the OEM ones. This puts added strain on an already weak cam chain. Once the cam chain stretches it will mess up the timing gear on the crankshaft. Once that gear is messed up, it's new crank time.

Remove the cover bolt over the cam chain tensioner & screw the tensioner in until it's all the way in & count the turns. If you turn it more than 2 1/2 turns, you cam chain is worn out.

i didn't replace the cam chain when i did the valves...forgot to order it. I replaced it when i did the piston about 3000kms ago so i wouldn't expect there to be too much wear yet.

But I'll keep that in mind, thanks for the info ?

the old cam chain was fine for the first 3000km with the new valves though. i only replaced it because i had it all apart for the piston swap (and i remembered to order it!).

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642MX

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god thats expensive. would ss valves wear faster or decrease performance?

im looking for valves for like 30-40 bucks a piece.

Let me try to set this straight for you. It seems like your confused. Titanium valves last just as long as SS.

SS valves require heavier springs. A SS valve kit, with springs cost just as much, if not more than the OEM Titanuim valves.

You won't feel any performance differences.

I always use OEM valves. They seem to hold up just fine when taken care of.

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robby111

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god thats expensive. would ss valves wear faster or decrease performance?

im looking for valves for like 30-40 bucks a piece.

I just looked at those prices real quick and guessed around $180 for the valves. If you think about it that isn't really alot of money. Think about how much you bought the bike for, spend on oil, parts an accessories, etc...And that is only the begining. You still have to get your seats drilled and all that:thumbsup:

Oh and you will save like $30 if you buy the valves here- http://www.yamahaparts-direct.com/fiche_section_detail.asp

Sorry TT store....:excuseme:

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grungle

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Let me try to set this straight for you. It seems like your confused. Titanium valves last just as long as SS.

SS valves require heavier springs. A SS valve kit, with springs cost just as much, if not more than the OEM Titanuim valves.

You won't feel any performance differences.

I always use OEM valves. They seem to hold up just fine when taken care of.

Totally agree that by the time you buy the heavier springs you're not saving much (if any) money. But I also believe it's a good idea to replace the valve springs when you do the valves anyway...

However I'm still of the opinion that the SS valves will last longer than the Ti, especially under less-than-ideal conditions (such as the extremely fine dust that I ride in). Unfortunately (or fortunately) I haven't worn out my SS valves yet so I can't make a direct comparison.

I could find very little info on the SS valves when I did mine - that was part of the reason I decided to do it. I was prepared to take a chance on the SS valves in the hope that I would get more life out of them. It's looking good so far - I'll inform the TT community when I've got some conclusive results.

If you're worried about it just go for the Ti. It's the safe bet.

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  • 5 years later...
Grand Master

J_YZ2fittyX

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Love this site, and I know they can get ya some stuff...they had a fender my brother in law wanted that NO other place he looked said they could even get them. However, I also know how expensive this CAN be...so finding the best price helps a lot of people out.  I got OEM valves (all 5) with springs and seals for $200/ free shipping. I don't know if thats a deal you will always find, just sayin its out there (got em on ebay). Guy had low feedback total (100%, just real low quantity), took the chance, had em in like 3 days in oem packaging, etc.

 

 

I bought new retainers and keepers and timing chain from rockymtn....only because i had a $25 gift card from a magazine subscription.

Edited by J_WR2fitty
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