Jump to content
Munition

RC Valve - How do they work?

Recommended Posts

I have a 2004 CR250.  Going through it getting her dialed in and fine tuned.  I haven't touched the RC valve, because at this point I don't know if I should even check it.  

So if I understand what I think I'm reading, the manual claims the RC valve functions to open the exhaust port larger when at higher RPMs.  This is done to help keep better bottom end power.  My question is how this works? The manual also talks about setting the RC valve troubleshooting, but doesn't really talk about how it works.  

There are two cables inside the RC valve, what I don't understand is how they are actuated? What is causing the RC valve to open? How does higher RPM cause the cables to pull, and open the valve.

This gif is a pretty simple way of explaining how a basic 2 stroke engine works.  I thought it would be a helpful illustration.  Perhaps as the RC valve is explained, my visual brain can make more sense of it. 

Arbeitsweise_Zweitakt.gif

Share this post


Link to post
Share on other sites

The 2 cable you see is actuated by a electrical servo motor mount in the frame, if you check in your rad shroud of if you remove the gaz tank, you will take a good look at it. The servo motor is commanded by the signal that the cdi send when it the engine past 8000rpm ( if I remember well) to open the powervalve. That's very simple. Now what you have to know is how to adjust the cable for that system work properly, fisrt check the condition of the cable, if they are kink, or have cut wire, or if they are hard to move, replace them. It's pretty cheap. After this, adjust both cable for they dont have slack, but do not over tight them, the valve is suppose to open and close freely. There some link that you can check to help. https://m.youtube.com/watch?v=PqJt_rZ7mac. http://motocrossactionmag.com/news/ask-the-mxperts-how-do-you-adjust-hondas-electric-power-valve-on-the-old-school-cr250s

Share this post


Link to post
Share on other sites

My Honda crm rc valve has been cut off and then now my bike can not pop a wheelie .  And now is like the bike is not functioning . Please can u tell me what to do

 

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×