Thanks, Mike. That helps a lot.

Chris

 

YYY.Guy,

Nice explanation! Good Job!

One of the things I found interesting when I pulled my carb apart is the fact that the KLX250S has a slide that is made from phenolic resin and not pot metal.

My KLR250 has a pot metal slide. The KLR650 has a pot metal slide. Most Harleys that use the CVK style carb have a pot metal slide.

"ThunderSlide" is an updated kit for the Harleys to provide a quicker throttle response. I've been wanting to get one for my KLR650, but after talking to some folks, they say the bike might start oscillating with it in. I'm still thinking of finding one and playing, if I can find it priced right. Maybe need to start watching EBay.

Once the pumper carb comes in, the KLX carb will probably wind up on the KLR. I want to see what difference the phenolic slide makes.

 

Yes, good explanation, YYY.Guy. And this also is a good place to contrast with one of the main differences between the CVK and the FCR pumper carb. Aside from the obvious difference that the pumper incorporates a pump to squire raw fuel directly into the air stream when you open the throttle to compensate for that extreme lean condition, the other very big benefit is that there is no butterfly valve. The slide is directly connected to the throttle cable. Thus, when you twist the throttle, that opens the slide to allow more air/fuel instead of having to wait for the vacuum to do it. So while enlarging the whole improves throttle response on the CVK, this is not even an issue on the FCR since the throttle response is as fast as it possibly can be since the throttle cable pulls open the slide. The only way to get faster is probably fuel injection where the injector can probably respond faster than sucking the fuel up from the carburetor bowl. But then again, the FCR has the accelerator pump to compensate for that.