Rad valve for KDX200?

[peterryan01]

Hello,

I was browsing the internet and stumbled across some information regarding rad valves. I did a search on this site for info, but only found a bunch of stuff about CR250's. I already have Boyesen reeds in my '01 KDX200, so I am wondering if a rad valve would actually give me significant power gains. I already have an FMF Gnarly pipe and Boyesen reeds installed. I am just wondering if it would be better to buy a Boyesen Rad-Valve, or skip it and replace my stock silencer and get the FMF Q (or Turbine Core II) silencer/spark arrestor. I am looking for low end since I pretty much only do trail riding. Which do you think is better?

Thanks,

Peter

 

[wibby]

I'd read this: http://justkdx.dirtrider.net/ Look at KDX Hop-Up Guide
in tech tips

Some people, have not been very impressed with the Rad Valve

 

[procircuit21]

I have the RAD valve on my '91 and I like it a lot, but I've heard a lot of people say the V-Force system is pretty sweet too. If I were you I would get the V-Force setup just because of all the feedback I've been seeing on them.

 

[skipro3]

Hi peterryan01
I had boyesen reeds then switched to VForce Delta. The only difference I can tell is that the boyesens produced a fluttering sound around mid band. Performance could not be determined. If the VForce is better, I couldn't feel it.

In searching for low end performance gains, first be sure your jetting is correct. The single biggest gain I made in low end performance was adding a flywheel weight. I was skeptical (I know, I can't spell and too lazy to use spell check) of spending $100 for a simple disc of metal, but once I did, I was amazed. The thing grunts up just about anything without stalling now. It is much easier to control and has turned single track side hill steep trails from terror to tame. As long as you can keep ANY forward motion, it doesn't stall. It also seems to kick start easier with the extra mass. Spend some time searching and reading the historical threads here and you will start to get a feel for what different options can do for your bike.

 

[weber.s]

A rad block does work, my mate has one on his 2001 kdx 200, bike goes well. I would get the power core 2 silencer anyway, the Gnarly, power core combonation is great, I have it on my 2002 kdx 200, and am very happy with it. If you are looking for bottom end power, try using your stock pipe with the power core 2 silencer, you will love the low down power, but be prepared to lose mid to top end.

 

[canyncarvr]

Note the terminology. A mototassinari vforce delta and the vforce delta2 are not the same thing.

If you notice a large difference upon radvalve install, chances are it's mostly that your reeds were shot in the first place.

Correct jetting is the single best thing you can do for your bike. Period. About the cheapest thing you can do, too!

 

[dirt bike dave]

I had a RAD valve on my '90 KDX200 (paid retail) and also on my KDX250 (buddy gave me a great deal on a used one).  The differences between the RAD valve and just having Boyesen reeds are subtle, to be sure.   My current bike has a V-Force on it, but it was that way when I bought it, so I can't say what change it made. 

I'd save the money you were going to spend on the RAD valve and put it toward jetting, suspension revalving, a steering damper and fresh tires.  All those things will improve your speed way more than a RAD valve, IMO.