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A buddy of mine has an '04 crf450. IF he needs new valves do you suggest stainless steel valves? If so, what company makes the best? If not, what type of valves do you suggest?

Also, I forget what the valves actually "seat" in (on?). (Yes, I am an UTTER newbie :D ). Do you suggest a new one.

What is the average cost of such adventures? Any help would be GREATLY appreciated!!!!! :)

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A buddy of mine has an '04 crf450. IF he needs new valves do you suggest stainless steel valves? If so, what company makes the best? If not, what type of valves do you suggest?

Also, I forget what the valves actually "seat" in (on?). (Yes, I am an UTTER newbie :D ). Do you suggest a new one.

What is the average cost of such adventures? Any help would be GREATLY appreciated!!!!! :)

Get a new 06 or 07 head for $230 and build it with SS valves. The newer head has better valve seat material and "shouldn't" need as many adjustments over time. Try Ron Hamp or AgentSmith, they both do good work with good customer service and price.

This link will even tell you how to do the work yourself

http://www.thumpertalk.com/forum/showthread.php?t=564710

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If you do want to rebuild your current head -- make sure you get the valve guides checked and the seats cut, if the seats aren't cut the new valves will not last.

Then you can stick in new seals, valves, and springs as the minimum. Its nice to replace the cotters and retainers as well. Retainers can wear.

I would go with some stainless valves, the last longer. Faction MX has a good kit. But the best stuff out there is Ron Hamps special coated ferra valves with his spring kit.

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Thank you so much for the great replies. It looks like I will try to hunt down this "Ron Hamps"!

Again, thank you all so much!!!!!

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I have the Faction kit in my currect CRF, no complaints here. The kit cost me $150, MX Time cut the valve seats for $65 and I did all the labor.

On my other CRF I have the Kibblewhite kit in it, no complaints either.

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AgentSmith is building my head as we speak! :-)

stock oem valves/seals/etc.

but Im using Conical Springs everything else is oem. i suggest use all oem stuff and just go and get a spring set.

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I am pretty sure WMR makes the conical springs. www.wmr1.com

Made from super clean valve spring quality wire and precision wound using conical spring technology that eliminates spring harmonics. The newest technology for your four stroke motocross motor. Price for set of 4.

They retail for $189.95 for the set of 4

This link may work, or you may have to go through their site to find them...

http://65.61.15.21/search_results.asp?txtsearchParamTxt=&txtsearchParamCat=24&txtsearchParamType=ALL&txtsearchParamMan=ALL&txtsearchParamVen=ALL&txtFromSearch=fromSearch

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Just asking, what makes the WMR springs so much better? I mean is spring harmonics that big a deal?

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thats my head!!! you bead-blasted the exhaust port didnt you ;-) now check your email and email me back the paypal info so I can pay you!!!!! :-)

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FOUR STROKE VALVE SPRINGS - CONICAL SPRING TECHNOLOGY

WMR Competition Performance has been testing and developing four stroke engine components for several years. We have introduced many new products into the market such as one piece titanium and stainless steel valves, high compression pistons, valve buckets, replacement valve seats, manual cam chain tensioners and Dual Valve Springs. All of these products have been designed to improve performance and extend engine life.

One common design challenge for all four strokes is valve train life. It has become evident that small bore four strokes have very vulnerable valves systems. Partly because of the high RPM's and excessive heat. Most valves trains will experience problems early in the motors life.

At WMR our focus has always been performance, we look at all parts of a motor to see where improvements can be made. One of the first things we looked at was valve springs. Improper spring performance hinders motor performance and can cause valve and seat damage. This condition is commonly known as "valve float" The traditional cure for valve float has been to add spring pressure, in an attempt to harness out of control valves, increasing pressure is not a guarantee that the spring will be able to control the valve. There is a very delicate balance between the perfect pressure and too much pressure. Adding to much valve spring pressure in an attempt to stop valve float can add unwanted friction and heat to an already hot running motor.

After thousands of hours on the track and Dyno testing various springs and pressures, it became very clear that the real problem was SPRING SURGE or spring harmonics. All springs have a propensity to vibrate at a certain frequency. The higher the RPM's the more likely the vibration. The less mass a motor has, the more damaging the vibrations can be. The principle factors affecting the frequency of the vibrations on a spring are the springs mass and its stiffness. When a spring is exposed to a damaging frequency as the motors rpm's increase, the vibration will rapidly build up to such an extent that the spring will no longer be able to control its own motion. So the question is, how do you keep valve spring pressure low enough while at the same time controlling valve surge and harmonics? One answer has been the use of Dual Springs. With the dual spring there is an outer and inner spring each having a distinctly different resonant frequency because of the coil and wire size. The two springs rub together during opening and closing to dampen and counter unwanted spring vibration, this is intended to deaden the vibrations and eliminate the harmonics. This concept works to a certain extent and sounds good, however the two springs rubbing together will generate excessive unwanted friction, drag and heat.

Spring surge was the driving force behind the adoption of air springs (pneumatic springs) on the 19000 rpm Formula One race engines. Formula One used Conical springs for a few years until they developed the pneumatic systems. The problem with small bore four stroke dirt bikes is, that it's not currently feasible to install air springs. If we want to come up with the perfect valve spring for the four stroke single cylinder motocross bike, then the primary goal is to find a way of eliminating surge (harmonics) without introducing destructive friction damping into the equation.

WMR has found a solution to this question, we have designed a Conical shaped spring. Using super clean valve spring quality wire that has been Eddy Current tested to eliminate impurities, our new Conical Valve Springs are the answer for the single cylinder cast aluminum, high revving four stroke motors.

The WMR Conical spring

The latest Conical Spring Technology

Eliminates Spring Harmonics

Lighter weight than stock springs

The best Quality Valve Spring Wire

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HOW WMR CONICAL SPRINGS WORK

We have talked about how proper valve spring design stops the spring from vibrating and harmonizing. If not stopped, the spring will surge and be unable to recover to its designed pressure at a specific installed height. WMR has found the best way to do this is to design a spring that has different size coils at each winding, that way the coils can not vibrate at the same resonant frequency. That is how the WMR Conical Spring is designed. The reason a conventional spring harmonizes is because every coil is the same size and for the most part equally spaced. A conventional spring is the perfect environment for the vibrations to become amplified, causing the spring to act as if it were sacked out. To demonstrate this, next time you start your bike, stand to the side and rev up the motor. You will see the seat squat down from the shock spring surging. This is the same thing that happens to your valve springs, they vibrate and squat down to the point that they no longer have the pressure needed to close the valve.

It is important to understand how critical it is for the spring to keep the cam lobe in contact with the valve at all times. If the springs are squatting or surging, they will be unable to recover to their designed closed pressure, this will leave the valve floating above the seat as the cam falls away from the valve. The combustion cycle will then slam the valve shut with thousands of times more pressure than the valve was designed to handle. Remember the valve is intended to be gently set onto the seat by the cam not slammed into the seat by combustion. If the valve is set gently onto the seat, then the seat is able to pull heat out of the valve head keeping the valves heat range at acceptable levels. If the valve is "floating" it never really gets enough time on the seat because it is bouncing vigorously before it is lifted again by the cam. If a valve does not have the ability to dissipate heat it will continue to get hotter and eventually start to deteriorate. After examining thousands of worn out KX250 and 450F’s, RMZ250 and 450’s,YZF250 and 450’s and CRF250 and 450 valve trains, it is obvious that the valves were floating and being beaten into the seats. The faster more aggressive rider will see problems earlier than a rider that shifts more often and keeps the motor in the lower RPM ranges, however every rider will eventually rev the bike and cause the stock springs to surge. Each time this happens, the valves will experience accelerated wear and can eventually fail.

There has been much talk about why it seems to always be the intake valves that have the premature failure. Keep in mind that the force causing the valve failure is happening during the combustion cycle, at that point the exhaust valves are already closed and not affected by the combustion. The intake valves are supposed to be closed also however because they are floating they are negatively affected by the unwanted forces. Exhaust valves experience more heat that can affect the guides and seats but typically exhaust valves last much longer than intakes.

With conventionally wound springs the coil size and spacing are all equal, the spring designer has little control over the springs open or over the nose pressure because he is most likely designing the spring for a desired closed pressure. For example a spring with a designed closed pressure of 28 pounds will have an open pressure of over 100 pounds. There is no control over the open pressure because all the coils are the same size. A valve spring will experience float at the lower end of the pressure range and rarely requires more pressure over the nose. It is beneficial to have the pressure as low as possible to allow the motor to rev easier and experience less unwanted forces witch act against its ability to be efficient.

With WMR Conical Valve springs we are able to control the open and closed pressures because of the spring’s unique design. A Conical spring with a closed pressure of 32 pounds can de designed to have an open pressure as low as 88 pounds. A conventional spring at 32 pounds would have an open pressure over 105 pounds. Any time you can lessen spring pressures you are helping the motor run better and be more efficient.

The way a Conical Spring operates is somewhat different from that of a conventional spring. On Conical Springs the coils become progressively smaller from base to top. As with any spring, given a particular wire size, the smaller the coil the stiffer the spring becomes. Because of this, a conical springs top coils are not only smaller and lighter but also stiffer.

While working the bigger coils at the bottom, being less stiff, compress before those at the top. As the spring is compressed during opening of the valve the bottom coils progressively settle down onto the one below. Soon as each part of the coil has settled on the neighboring coil beneath, it is removed from the effective valve mass equation as far as mass in motion and spring weight are concerned.

By the time a valve controlled by a Conical Spring reaches full lift, only the small top coils are actually being moved and the spring’s stiffness has escalated considerably. In basic terms this means that at full lift the effective spring mass is a little less than 10% of the springs total mass. That is 10% as compared to 30% of a conventional spring. So with Conical Springs, a typical 100 gram spring reacts in the valve train as if it were 10 grams. This savings can be as much as the equivalent of a steel valve versus a titanium valve.

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Now this all sounds pretty good, but it gets better. Since the top coil is smaller you can use a smaller and lighter retainer. That means, the over the nose weight savings of a Conical Spring is substantial. At 13000rpm's even a feather on the top of a valve would feel heavy.

I have tried to explain in simple terms how WMR's new Conical Valve Springs can eliminate spring surge, and valve train mass, but I cant stress enough how important that is to your engine and valve train life, especially in a single cylinder 250cc & 450cc motocross bike that is constantly operating at different loads and RPM's. The fact that a single cylinder lightweight MX motor is built for maximum strength at minimum weight actually works against eliminating unwanted resonant frequencies, there is very little mass in the motor to help combat against vibration. As the rpm's increase so does the potential for harmonics and valve spring failure. We believe the stock springs have been the cause of many of the heating issues as well as the valve train failures.

We are very excited about our Conical Valve Springs. They have proven they will reduce heat and friction, and control the fragile valve trains in all brands of four strokes. WMR makes Conical Valve Springs for Honda, Suzuki, Kawasaki, Yamaha, and KTM. You can call the shop to learn more @ 1-866-WMR-RACE

CONICAL VALVE SPRINGS - MORE INFO ABOUT WHY THEY WORK

In service bulletin 005 we began to explain how WMR Conical Valve Springs work, the following information will explain Why they work!

Let’s talk about spring Surge or Harmonics. As we stated before spring surge begins at different points for any given spring, depending on the springs mass and stiffness. The stiffness is determined by the type and size of wire and the size of the coils. For example at a given wire size, a small diameter coil is stiffer than a large diameter coil and each size coil will have a different resonant frequency. In simple terms each size coil will vibrate at a different point. Each time the cam lobe strikes the top of the valve a vibration is sent through spring downward and then back up. As the wire vibrates it losses its natural ability to recover and return to its original position.

As the cam or rocker arm strikes the valve, vibrations are sent through the spring traveling up and down rapidly. This motion counteracts the spring’s natural ability to return to its original position. Spring surge will increase as the rpm's raise rendering the spring virtually useless.

Now imagine the vibrations caused when the spring is being struck about 200 times every second plus add the vibration caused by the rest of the motor, the spring will end up vibrating out of control. When this happens, the valve will float and cause loss of power as well as excessive heat and wear. We call this problem Valve Float. Sometimes the valve head may even strike the piston and send more unwanted vibrations through the valve train, piston and to the crankshaft.

With a conventional valve spring, each coil is the same diameter, as the spring compresses, it moves all the coils together proportionately from the top to the bottom. All coils are in motion at all times, this adds to the effective valve mass (we will discuss this further below) Since all the coils are the same size, they all have the same resonant frequency therefore they will all vibrate together and will actually "harmonize" with each other amplifying the negative effect of the vibration. That's why it is called spring" Harmonics". If you have ever played a guitar you know that if you place your finger against a vibrating string you will deaden the vibration. With a conventional valve spring all the coils are free to vibrate and there is no way to stop them .One way to stop the unwanted vibration is to deaden the wire with contact from an outside force like your finger does with the guitar string. The most common way to do this has been with a Dual Spring. Dual springs consist of two constant wound springs one inside the other. Each spring has different size wire and therefore a different resonant frequency.

The inside spring is meant to rub against the outside spring and deaden the vibration. This works pretty well at reasonable rpm's but looses some effect as the rpm's increase. The main problem with this kind of spring is the excessive friction and heat generated as they rub together as well as the extra weight from the two springs. This can cause more problems in the motor than the original harmonics did.

With the new WMR Conical Springs everything I have just told you about the conventional spring changes. First since the coils at the bottom are bigger and get smaller as they go up, the bottom of the spring compress first. As the bottom coils compress they settle onto each other and deaden themselves. Now with a conventional spring this would be called coil bind and is not a good thing, but with the WMR Conical Spring it is a very good thing. The spring is not coil bound because the top coils are still in play. The bottom coils have been deadened from vibration and have also been removed from the effective valve mass.

Notice the size difference of a conical spring (on left) compared to a dual spring. Conical spring is 32% lighter.

It may be hard to see in this photo, but notice how the bottom coils have compressed and been removed from the effective mass of the spring, leaving the smaller lighter coils on top to do the work. The entire spring is used to eliminate surge.

A heavy effective valve mass is a valve trains biggest enemy, motor builders are always looking for ways to lessen effective valve mass because by doing so they will eliminate stress on the motor. Less pressure means more power, rpm's and torque, less heat and longer engine life.

It has long been conventional wisdom to increase spring pressure to lessen valve surge. This works to a certain extent, because as the springs mass and stiffness go up so does its ability to resist vibration The only problem is the stiffer the spring the more stress on the motor. Also if you were to make a conventional spring stiff enough to stop all harmonics at 13000 rpm's it would be too stiff for the valves, seats, cams, cam chain, buckets etc. The effect could ultimately be worse than the original surging valves.

It is easy to build a low revving four stroke motor such as a lawn mower, because you can run very light valve spring pressures and balance all the forces so they work together. The problem we have with the new high performance four stroke motocross bikes is we need high rpms, good horse power, torque and light engine weight. All of these things work against the old way of thinking when it comes to valve springs.

In Formula One the best engineers in the world have been working on these issues for a long time, the concept of a conical spring was born in F1 and was working very well until they invented air driven valves.

F1 motors are revving over 19000rpm's for long periods of time and engineers needed to remove valve spring surge from the equation. They were able to do that very effectively with Conical springs. With our light weight MX bikes air springs may be a long way down the road but WMR Conical Springs are here now. At 13000rpm's the conical spring will do a super job of eliminating valve spring surge and help lengthen the life of our valve trains.

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Because the spring is working more effectively and because we no longer need to increase pressure to combat harmonics, we are able to use a smaller wire size and open up the coils. This result is a lighter spring creating less effective valve spring mass. Can you imagine the forces that develop from the valve opening and closing? Just like Newton's law of motion states "An object in motion stays in motion until an equal and opposite force acts upon it" In other words, The cam is pushing on a valve in motion trying to change its direction hundreds of times a second. The heavier the effective valve mass the harder it is to change directions, heat and pressure will increase. That is why it is so important to get the "over the nose pressure" and the valve train weight down as low as possible.

Remember how the top coils of the WMR Conical Springs are smaller than the bottom ones? The smaller top coils are the only ones in play at full lift and because they are smaller they are lighter. Also because the bigger bottom coils are less stiff, they have already compressed and are no longer in play. This result is the effective mass of a conical spring is reduced to about 10% of the spring’s original mass. This is in sharp contrast to a conventional spring that sees about 30% of its original mass. When you combine the Conical spring’s lighter weight with the greatly reduced effective mass it's easy to see how beneficial the Conical design is.

The last piece of the puzzle is the retainers and keepers. If you can reduce the weight of these items you can further improve the entire system. Because the top coil is smaller than a conventionally wound coils, the retainer can be smaller. WMR offers lighter Titanium retainers for Honda, Suzuki, Kawasaki and Yamaha.

WMR Competition Performance has risen to the top as the Premier Four Stroke Motocross Race Shop on the East Coast. We offer everything for Motocross such as full bike services, modified motors and suspension, parts and accessories, riding gear, pit bikes and more. Our full machine shop specializes in head work, installing bronze seats and guides as well as repairing damaged heads and making custom components that improve the performance and handling of your machine...

We are very excited about the Conical Spring technology and are proud to be at the fore front of its development in the motocross market.

You can call and talk to a technician at 1-866-WMR-RACE toll free if you have any more questions, our visit our web site at www.wmr1.com for frequent updates.

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They seem as though they provide a bit more seat pressure as well, compared to Ferreas or Exceldyne Kobe wire. They are nice.

Did you measure the seat and full lift pressures?

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I have the Faction kit in my currect CRF, no complaints here. The kit cost me $150, MX Time cut the valve seats for $65 and I did all the labor.

On my other CRF I have the Kibblewhite kit in it, no complaints either.

Forget the Kibblewhite's. They are heavy and are 2-piece. Ferrea SS valves, springs, retainers etc......Talk to Ron Hamp. He is the only way to go. Give him a call! (989) 463-1267

theDogger:applause:

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Personal opinions...thats all nothing to get annoyed at...this was the first time i had to do my valves on my head and i heard great things from agentsmith and the pix he sent me of mine are awsome so for me to tell people he is really good to reccommend him...im sure a major engine guy like Pro Circuit, Varner, etc. im sure they do excellent work but for the price its just not in the average workers budget like mine...agentsmiths job was $75.00 and the pix i saw of my head they are deff. worth it. i spent more on the parts than the actual labor...but i work in a car dealership so im used to seeing numbers like that LoL

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Why does everyone on here always say Ron Hamp and MRD are the only ways to go?

That shit is getting annoying.

Pretty simple they have developed very good reputations on TT. I personally have a MRD exhaust that I have bent up 2 times and I sent it back to Dave and he fixed it new with no problem. For that reason alone and that the exhaust works. Ron Hamp...I have sent several people to him for head work and they have been very happy with no issues and Ron backs up his work. Ron even builds engines for some of the Satellite race team on the national circuit.

But most of all when you call either shop you talk directly to the guy who is doing the work. Not some 18 yr old kids following instructions like a Pro Circuit. No don't get me wrong PC can make some get stuff but you need to talk to the Race Shop to get the right stuff done. I have a complete PC head on my bike (ported Ti Valves and copper seats) but it was done by the guys that do the race engines for the teams not what the general public gets.

I guess the bottom line is that these are small shops that produce quality work and back it up 100% Also price wise you can't beat them!

theDogger

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