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I thought Stainless was the answer....

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After 35 hours my stock Ti valves were at 0 (both)... Oh well.

Now after putting in KW SS valves and spring kit, also getting the seats matched, at a total cost of $1000 :devil:. The friggin' left valve is at 0 again!!! (another 35 hours)

The right is still at 6.

WHY WHY WHY???!!!!

I thought stainless valves were the cure.... now I'm wondering if the valve head is going to pop off!!

Not what I need running through my head while doing 100 footers at 38 years old.

This sucks. :thumbsup:

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That sucks man.

I just had KW installed. $1000 :thumbsup: is kinda steep. Did you just bring the head in?

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Ya only the head...

500$ for the valve job and new X guides....it was a little steep. He put the valves and springs in.

And 450$ for the valves and spring from the US.

I guess I will just shim the left and see if it goes down again. :thumbsup:

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I don't know what to say but my old CRF450R was fine 18 months after I had the SS and KW stuff done. Is there a chance that the job wasn't done properly? :thumbsup:

When I have to do it again for my CRF250R, I think I'm going to send the motor to Eric Gorr. According to the web site, it seems very ligit and professional. The price is reasonable too.

The hardest part for me is getting the motor out and shipping it to him.

Eric Gorr

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That's a classic symptom of incorrectly cut seats or bowls. Typically the "machinist" cut the seat mating surface too thin or positioned it wrong against the valves seating surface. Either way as the valves sink their way into the head you'll have to adjust them. It will either stop sinking or you will drop a valve. Even if they stop sinking you've still got screwed up seats so power & longevity will be down & the only way to fix it is oversize valves & cutting the seats correctly, or replacing the seats. Either way you got burned.

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you guys need to start checking your spring pressure before installing them a stock spring is @ about 40 pounds on my tester thats not enough to control the heavy steel valve i had measure some after market springs after 8 mounths of use and worn out steel valves and they were down to 25 pounds and sacked .100 inch it would be interesting to know where your springs are @ right now.

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Now you guys have me thinking &%$#@!...

I guess there is only one way....pull the head off.

I can't picture it being the seat cutting ...it was cut on a SERDI with brand new pilots (I guess my $500 covered the cost of the new carbon steel pilots)

I'm trying to check the installed valve height, and it looks real close but I'm not being that accurate with the head in the bike.

So off she pops.....

Thanks for the help...you guys are the best

:thumbsup:

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Serdi pilots are solid carbide and are 110$ US ea.

You might inform the individual that informed the work and ask his opinion.

At least give him the feedback.

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you guys need to start checking your spring pressure before installing them a stock spring is @ about 40 pounds on my tester thats not enough to control the heavy steel valve i had measure some after market springs after 8 mounths of use and worn out steel valves and they were down to 25 pounds and sacked .100 inch it would be interesting to know where your springs are @ right now.

I took the head off and the valve is cupped just like my Ti ones were...(2 sets of Ti's went in before. Stock lasted 30hours, next set, the left was gone in 4 hours)

Ron are you saying 40# isn't enough for a SS valve? I checked the specs of the spring kit I got from WebCam and the intakes are 40# at the installed height (1.280).

I'm going to get the springs checked tomorrow...but now I don't know what to do.

Do I get 1 new SS valve and run the same springs if they check out at 40#...or do I grind the old valve and shim the spring.

OR do I put stock Ti and springs back in....? :thumbsup:

How much $$ do I have to blow on valve work...I don't even ride THAT much. I'd say I have about 80 hours on my 03.

Do I have a bad lobe on my cam, that snuck by the Honda QA team, and messes up my left side?

Should I just shim this valve and sell the bike and pass on the problem?

Any idea's of what to do now would be appreciated

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I don't know what to say but my old CRF450R was fine 18 months after I had the SS and KW stuff done. Is there a chance that the job wasn't done properly? :thumbsup:

When I have to do it again for my CRF250R, I think I'm going to send the motor to Eric Gorr. According to the web site, it seems very ligit and professional. The price is reasonable too.

The hardest part for me is getting the motor out and shipping it to him.

Eric Gorr

eric gorr and rich rohrich did my 450. it runs very strong with the stg II hotcam and jemco exhaust. and they do stand behind their work. for example, when they had problems getting my head back to me on time due to a problem not at their shop but at an outside shop they sent me a new wiseco 13:1 piston kit as an apology for keeping my head only a week longer than they stated. if that isnt a reason to send them your stuff then nothing is. and eric answers his phone just about every time i call. :devil:

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The stock CRF450R intake installed spring pressure is 28# at 1.395".

The 1.395" is the distance between the underside of the retainer and the top of the base where the spring comes in contact with those two surfaces.

The KPMI kit increases the installed intake pressure to 40#.

The stock exhaust spring pressure is 45# at 1.465" with a steel valve and a wicked rocker ratio.

I've built several heads using the conversion kit for riders out here with no problems. Those include several motard guys. One of the guys I work with made a true 54 hp at the rear wheel. I know it's not as much as a full blown deal, but we didn't make any carb mods, and the pipe wasn't that great. He raced every weekend and practiced during the week. (Doesn't anybody work anymore?) We went a full season on the head with no problems. The bike peaked at 8800 held there till til about 10,000 and at 11,000 was back to the 45 HP we started with before the mods. Of course we've sold thousands of these kits world wide to folks who tell us it's solved the problem of valve face recession they were having.

Typically when I see valve face recession on the steel valves it has to do with set up, or guys keeping the throttle pinned to the rev limiter. For instance I talked to a guy yesterday who just happened to re-check the valve adjustment on his head before he took it out for a ride (the guy who did the work set it up for him) and it had .018" clearance instead of .008". That would have beat the valves sensless in about an hour. Of course seats that are out of round, or guides that are worn will also cause recession problems.

If you keep the engine up against the limiter you'll be running the springs at their limit. The rev limiter isn't a throttle stop to run up against constantly, it's there to let you know you are at terminal speed for the components, and if you spend a lot of time there you are going to cause parts to fail.

I'm not singling you out, because for all I know you never hit the limiter. This is more an info update based on what I've seen myself, and learned from talking to builders from around the world. The consensus is that riding style can be a contributing factor to early valve face recession.

It's difficult to guess what happened in your situation, typically I would need to disassemble everything and check the heights and pressures to verify everything is where it should be, then the relationship between the surfaces needs to be checked. Finally the appropriate components would have to be checked for wear. Unfortunately a mistake that was made initially isn't always discovered, and the head is put back together with new parts, and works fine, and you never know what was wrong. It's nice that everything works finally, but it's a bummer not to know why it went bad to start with.

Mike

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Thanks for your errudite response, Mike.

I appreciate you stating the facts or what you know to be fact instead of propogating speculative highschool physics.

And there wasn't a single buy KMPI anywhere in your post!

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Klasic, What did you end up doing to fix your valve problem? What are most people doing and is it working?

Buz

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Klasic, What did you end up doing to fix your valve problem? What are most people doing and is it working?

Buz

I don't really know what to do... I just called WebCam now and ordered another valve. I guess I'll just replace the valve.

I checked out the springs and they are 40# and 42#...so I guess it wasn't caused by a sacked spring.

Two car engine builders checked out the seats and said they look fine.

Maybe I'll put in a Stage2 Hot cam as well.

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