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Kibblewhite Intake Valves with OEM Springs?

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Is it ok to use KW Black Diamond Intake Valves with OEM springs, stem seals, cotters, retainers and seats?

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My problem is I have a TRX OEM full valve kit on the way to me and have just had brought to my attention that the intake valves are titanium.

Part number 14711-MEB-670.

If I go down the TRX OEM path with the SS valves I need part number 14711-HP1-670 but they are 36mm compared to titanium being 35mm.

Extra cutting of the seats will be required, is that done easy enough? I am using a reputable shop to do the work.

All other parts in the kit, stem seals, retainers, cotters etc match the 450X part numbers so should be ok there?

Edited by Razman11

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I am confused if you are geeting titanimum or stainless steel, but I thought when you switched out to the SS valves you need to get a beefier spring to help control the heavier valve. 

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i thought TRX valves were steel- heavy compared to stock x or r valves kw are heavy so use stronger kw springs designed to control heavy'r valves or trx springs ?

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The TRX valves, which are steel, use the EXACT same spring as the CRF's that use Titanium valves. I'm sure the reason Honda spec'ed those is that the quad isn't expected to see the same RPM's as the CRF.

If you are the type of rider that is banging the rev limiter constantly, the Kibblewhite springs would obviously be the better choice.

That being said, most of us aren't riding at 10,000 RPMs, so valve float isn't ever an issue.

We have been using that system on Baja and Desert race bikes for years without a single failure on literally thousands of engines.

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I run the trx valves with the stock springs installed by AS racing, I do hit the rev limiter but I don't live on it, I have had no problems with valve float. I have 5hrs on the motor since the install and the motor runs perfect

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I would use the Kibble white springs etc ..

Pretty sure kibble white come with double valve springs. I would not OEM valve springs on stainless valves.

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Pretty sure kibble white come with double valve springs. I would not OEM valve springs on stainless valves.

How come?

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How come?

I have installed ProX stainless valves and Fraction Mx stainless valves. Both had much more heavy duty springs compared to the OEM spring. I haven't installed Kibble White valves. But pretty sure they valve kits come with dual springs(double springs). Obliviously the stainless valves are heavier and require a higher spring rate. Edited by hondahead98

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I have installed ProX stainless valves and Fraction Mx stainless valves. Both had much more heavy duty springs compared to the OEM spring. I haven't installed Kibble White valves. But pretty sure they valve kits come with dual springs(double springs). Obliviously the stainless valves are heavier and require a higher spring rate.

You understand Honda uses the same spring whether its holding the titanium or stainless valve right from the factory, so with that being said it isn't so obvious. There is absolutely nothing wrong with running the stock OEM spring set up on a stainless valve.

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Pretty sure kibble white come with double valve springs. I would not OEM valve springs on stainless valves.

 

The double coil spring Kibblewhite uses is not due to the fact that a single coil just isn't strong enough, so they use two.

Kibblewhite uses two due to the fact that a single coil has a resonant frequency. At some rpm, the spring will tear itself apart. Using a second coil of a different size/wind negates the harmonics that can cause failure.

Why do you think that the Honda engineers use the CRF spring and the TRX valve in the TRX450R head? I imagine that they do some kind of testing as opposed to just pulling parts off the shelf...

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Pretty sure kibble white come with double valve springs. I would not OEM valve springs on stainless valves.

 

Yeah KW uses a double spring set up for their heavier valves and also consider it a performance upgrade. I would agree with you and not use the OEM springs etc with the heavier valves especially on an engine that gets raced or run hard, or on a 250.

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The double coil spring Kibblewhite uses is not due to the fact that a single coil just isn't strong enough, so they use two.

Kibblewhite uses two due to the fact that a single coil has a resonant frequency. At some rpm, the spring will tear itself apart. Using a second coil of a different size/wind negates the harmonics that can cause failure.

Why do you think that the Honda engineers use the CRF spring and the TRX valve in the TRX450R head? I imagine that they do some kind of testing as opposed to just pulling parts off the shelf...

 

It would be cool to have access to some of their tests and results.

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Yeah KW uses a double spring set up for their heavier valves and also consider it a performance upgrade. I would agree with you and not use the OEM springs etc with the heavier valves especially on an engine that gets raced or run hard, or on a 250.

Do you think I made a mistake by using OEM stainless valves and OEM springs? Do you think honda made a mistake when they designed them? Should I redo my engine? Should CRF Doc recall all of his race engines?

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Do you think I made a mistake by using OEM stainless valves and OEM springs? Do you think honda made a mistake when they designed them? Should I redo my engine? Should CRF Doc recall all of his race engines?

 

No not at all, its been done before and sounds like its worked fine for alot of guys.

  

I dont think that maybe its the best choice for everyone but it is an option.

 

Im not knocking you for having it done.

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I'm guessing only the NSA has that info...

 

Oh yeah its highly confidential :thumbsup:

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