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The valve fix... I hope

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Okay Guys... I've been waiting to talk about this until I knew it was really available. Here's what I've done for my valve fix.

First... I needed the stainless steel valves. I called Ferrea ( www.ferrea.com). I got a set of stainless, including shipping and everything for $140. Actual charge was about $33.70 per valve!!

Then... I hooked up with WMR. I did the head swap for $325 as a precaution. I liked the idea of the oil groove being machined into the intake cam journal, and the copper/nickel valve seats were just a plus.

And the last piece of the puzzle... WMR has just released their bee-hive valve springs for the stainless valves. I don't know the price yet (...the bill will be in the box when it arrives Monday). I'll try to explain what they told me about these springs. Normal springs, turning at such high rpms reach a point where they start to experience a harmonic vibration. All the coils being the same size will cause them all to vibrate at the same level, resulting in a spring that is more or less just quivering as opposed to expanding and contracting. Everyone tries to combat this by using stiffer springs, but the problem isn't cured. By using springs that have a different size coils through it, it eliminates the harmonic vibrations. Without having to fight the vibrations a ligher spring can be used, resulting valve springs with a tension almost similar to stock.

Now... I'm not an engineer by any stretch of the imagination. But, if what they say is true about the springs, I'm thinking this SHOULD be the end of the valve problem.

If you don't do the head swap, and the springs are $200 (shooting high), it's still a potential fix for around $340.

As soon as I get it bolted together and get some seat time, I'll post the results. But the potential is there for no loss in performance and a huge gain in reliablility.

...and maybe I can stop bagging on this otherwise great bike. :cry:

~Tex

RMZ+SSv

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I'm still lost on the spring issue, Like I stated before most of our f's are over the year mark now, and we were running the stock valves and springs with no problems, I've heard just about everyone on here talking about spring failure or not enough tension, We litterally run the piss out of these bikes, Maybe its the castrol 20/50 acteivo, maybe our time is comng soon. Good luck on the fix Keep us posted, Where did you get the stainlee steel valves from, got a number.

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The spring issue with stainless steel valves is getting them strong enogh to keep those heavier valves moving as fast as they need to, without being so strong that they more or less get in the way and slow down the works.

With the stock valves, I don't know about the whole heavier spring issue. Though I haven't really studied it out there, I don't know that I've seen anyone's valves last longer with heavier springs.

I'm looking for bulletproof, and I think this will be it. I had ZERO problems for 9 months. Then had to replace a valve and it lasted 2 months. Now that I'm doing this a third time... I want it to be the last time. My yammies ran well over a year without so much as a peep from the valves. This remedy will either fix the valve issue, or will make the bike a better trade in on a blue bike.

~Tex

RMZ+4ss

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tex cant wait for your post on your setup think you are onto something iv been thinking about stainless valves for a while now and now someone has had the balls to go to stainless valves shows your dedication the the green machine hopw al goes well and the kawaka rides and revs and pulls as hard as it did with the stock valves and and springs if it does i will be getting your number and calling to get you to order the hole setup and sending it to australia for me cheers goodluck

Brad

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When I spoke to bob at WMR, he told me that the springs might effectively cancel out the weight of the stainless valves. The springs and retainers are part of the effective weight of the valve, and the retainer and spring are much smaller with the beehive spring setup.

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Makes perfect sense to me.

I believe ferrea has a picture of similar springs but for an automobile.

Congrats on the find and hopefull fix.

And please,,please keep us posted. Not that you wouldn't. :cry:

Joe

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The spring theory makes sense to me now, I was wondering what companies were trying to achieve. The stronger spring seems like it would put more force on the seats and be bad, yet if it started to resonate, that would be worse. So its like they picked the lesser of two evils.

Actually resonance is more like the spring going nuts and expanding wildly and way too far. Like some past bridges have done before they collapsed.

The spring is just lost energy your engine has to overcome to run. Some power has to be used to squash all the springs every revolution, and you don't get that back when they expand, well maybe a little bit. You can easily feel the difference for yourself. Take out the cams and spin the engine over with your hand on the kicker, its easy. Now put the cams in and its way harder. thats what you engine has to fight against. Maybe some day pneumatic valves or something will help even better. Ducati doesn't use valve springs, they mechanically drive the valve both directions, thats a pretty cool setup. So they dont have the power loss from it, I assume thats one reason why they do it.

Anytime you have something moving and add mass to it, it will be a bit harder to get to move quickly. So heavier valves will have some flywheel effect, now those who wanted a flywheel weight may not have to. They are moving pretty fast, so a little weight may go a long ways. You might like it better, who knows.

One thing I find odd about your experience, and I have read it several times on various posts, haha, is that after the new valves, it didn't last as long as the original. Why would this be? More hours on the bike, more high rpm riding? What changed between original and after the shop did the work? Maybe they ground the seats and did a crap job? Or maybe they lapped the valves a bunch. I think it should have lasted as long as original, you got some bad luck there.

I am also curious about the hard coating as people call it. Now I know it is done on steel parts, carburizing it's called. But I don't know what they do for titanium, maybe its a similar thing. I will have to ask around at work, maybe someone there knows more about titanium than I do.

I don't know the theory on the new seats. You don't want a soft seat because it will just smash and be just as bad as the valve problem. Maybe its more springy, so it hits the seat and can deflect some, yet spring right back to where it was. The valve seat shape seems important to me, they seem like such a skinny contact area per spec. If its wider it should spread out the load and help. Maybe it doesn't seal good that way, maybe it had to deform a bit to seal, I dunno.

Anyway, :cry: thumbs up to you for trying this. I hope it goes well. I have heard good things about the stainless valves in other engines. I hope the quality of the parts are good. Springs may be a bit tricky to make last well. But it sounds like they know what they are doing. It looks like you made a good choice.

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Ducati doesn't use valve springs, they mechanically drive the valve both directions, thats a pretty cool setup. So they dont have the power loss from it, I assume thats one reason why they do it.

man, that desmodromic design must slicker than a perpetual motion machine. :cry::cry: i guess ducati must operate in a different universe if they can avoid a power loss (ie using enery) to open and close a valve.

p.s. Mr. Hooke says you get more than a little bit back

http://scienceworld.wolfram.com/physics/HookesLaw.html

and

http://scienceworld.wolfram.com/physics/Spring.html

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Somehow I think you are trying to make fun of me. But what you said doesn't make sense.

I didn't say Ducati takes zero energy to run its valves, I said it doesn't waste the energy compressing a heavy spring like most engines use. You were way off my point if you thought I was trying to say someone made a perpetual motion machine. Quite the opposite actuaally. Had to much to drink when you read it? Not enough sleep? :cry:

You site those equations, but not how to apply them. Hey man thats about meaningless. I know about those equations. Sure a spring gives back the energy when it is released, in a perfect world its 100%, but its never quite 100% in reality, so there is a small loss right there.

My point was how it works in an engine. In an engine the cam pushes on the spring to compress it, and that takes energy. Do you think the spring helps spin the motor on its way back up to give the energy back? That was my point right there. Maybe I should have put a question mark in my previous post. It seems like it would only help spin the motor for a little bit as the cam lobe passes its largest diameter.

Since you are getting down to equations and such, I may as well go further, you also have losses when trying to scrape a cam lobe across the bucket, even higher friction when the spring is stronger.

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OK... enough squabbling... let's find a fix.

Now... I have a serious question. I have two of these bikes and they are both eating the same intake valve. I agree that the light valve spring may be allowing the valve to float, causing the damage. I also agree that stainless steel may be the way to go. So, here is my question:

Without a proven fix out there, why should we experiment with all 4 valves when only one valve gives us problems?? I am thinking about a new valve spring and/or a new stainless valve... but just one!! After all, the other 3 valves are working just fine.

Does this sound crazy?

Jimbo

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jim_bo,

it is more than just the one valve. both intakes in texlabo's head were ruined. the left intake just wears out faster. the right one can and will fail in the same way, it just takes a lot more time. in his situation, it took about 11 months for the right one to wear out.

on a kxf that was in the same shop that texlabo's cases were split in, all 4 valves were ruined. yes, even the exhausts. they had the same valve face cupping that most see on the left intake. the intakes were still in the head because the stems were mushroomed to the point they would not go through the guides. the stem were going to have to be cut off for their removal.

all 4stroke motors (even ones in cars) can have these exact same problems. however, most motors don't spin 13,000 rpm and put out 30hp with only 250cc's. that's 120hp per liter and means a '04 mustang should produce 570hp in oem stock trim. the problem is that either suzuki or kawaski cut some corners in the design and manufacturing processes of this motor. those short comings are being seen by a LOT of the customers. this is a very unfortunate situation.

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Jimbo... here's my take. There's no proof that it would cause any problems to install 1 valve. BUT.. I would think to keep things balanced, do to the high stress of this motor, I would do both intakes or both exhaust or all 4.

At $34 a valve, it's my belief that replacing all 4 valves is the only way to go. Valves and springs will run around $300. If you only do 1 or 2 valves, it's only a matter of time before the others go. If you're lucky you'll just end up buying the other valves anyway... if not, you'll be buying these valves and a head and a crank and a piston and a.....

Just buy the valves and springs and be done with it. "pay me now... or pay me later..."

~Tex

RMZ+ssv

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Spend $300 now... it's cheaper than $1200 when the valves come apart and you have to replace the entire motor.

Save up... buy a couple parts at a time while the bike is still running. At the very least, buy the two intakes and 2 springs. It sucks. But ignoring it will only cost more down the road.

~Tex

RMZ+ssv

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I would like to thank all of those who have shared helpful information so that our kxf/rmz's keep running and riding as good as possible. This forum helped me with alot of the prep i did before i even rode the bike ie; airbox re-seal, cooling system mods , suspension fixes , jetting and such. the bike has been a blast to ride! now i will pick my words carefully 'cause i'm more than pissed. i haven't ridden my bike more than @12-15 hours since i bought it in may because i work alot. due to low hours and the fact that i take very good care of my things it is in showroom new condition. it runs great. it carburates so well that a half hearted kick will bring it to life and it never hiccups or backfires.it now runs so cool that it may run too cool when winter comes. i just can't accept that i and not kawasaki/suzuki have to shell out 300-700 dollars to fix a problem that they created with poor manufacturing and poor quality control. i have a thought of trying to get suzuki ( mine is the rmz) to take the bike back and give me a 125 or 250 two stroke. it is now very apparent that premature valve troubles are not isolated events with this bike and also there seems to be consistent pattern and plenty of evidence from owners such as Tex and others. sorry but i had to rant! i want out . my bike is for sale and i will come back to the four strokes when #1 suzuki actually makes the whole bike, #2 when they are as reliable as the yzf's seem to be. best of luck to all and happy riding. mike. oh yeah, this is the best forum on the web.

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When I spoke to bob at WMR, he told me that the springs might effectively cancel out the weight of the stainless valves. The springs and retainers are part of the effective weight of the valve, and the retainer and spring are much smaller with the beehive spring setup.

Allow me to spread a little more light on the issue of Effective mass.

The basic way to establish effective mass is to add the weight of each component in the valve train being affected by the cam. You have,

1)The valve

2)The spring

3)The retainer

4)The keepers

There are also buckets and shims, but for this exercize we will not include them.

If you can reduce the weight of any of these items you are reducing the effective mass.

The effective mass of a stock intake valve is 47.5 grams. When you change to stainless valves with stock springs, retainers and keepers the effective mass becomes 57.5 grams. Now when you go with the lighter WMR Conical Springs and Titanium retainers, your effective mass goes back down to 48.5 grams.

It is easy to see how the WMR Conical Spring almost cancels out the weight of the stainless valves. We are currently working on even lighter retainers and keepers that will bring the effective mass below that of stock.

To fully appreciate the benifit of the WMR Conical Spring you must not forget the fact that harmonics are eliminated and the over the nose weight is one third of a conventional valve spring due to it's unique design. The bottom line is a lighter over the nose weight and a controlled valve. This is very good news for anyone who owns a modern day high revving four stroke. You can go to the Tech Tips section at www.wmr1.com for more info and frequent updates and testing results.

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flarmz, have you actually had a problem or do you just like wishing for the impossible. nobody will take a used bike and give you another new bike. I don't care what company you go to. If you don't ride much you're probly one of those guys that sits on the thing and pins it before it's broken in, try doing that with your car and then ask them for a new one cuz it doesn't perform correctly.

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the one thing that takes away from the usefulness of these forums are useless personal replies. the internet allows some too much freedom to say what they wish who might not otherwise. don't suppose a thing about me or my knowledge. ask Tex wether or not he was concerned about his motor 7 months ago. if this bike were a car it would've been re-called. i choose to get rid of the bike before it costs me a pile of cash. i won't reply again. say what you wish if it makes you feel better.

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OK... let's save the whining for the Off Topic forum.

I think I am going to try the stainless route with a new spring kit. It should end up being a $300 job... I just hope the problem goes away.

I'm not going to send my head in for a bunch of work that I am not convinced is needed.

Jimbo

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