CV Performance Products Review

Hi, I'm Bob LaRosa. Welcome to "Fix My Hog." What I have on the table here is one of my favorite Harley-Davidson items. The CV carburetor, constant velocity. What this carburetor did was revolutionize the way the carbureted Harley-Davidson engine ran. Prior to this, it was a Keihin butterfly carburetor. That meant it had a butterfly in the venturi, and that was what operated the entire fuel circuit system inside the carburetor. In 1988, Keihin, the same maker of the true butterfly, introduced the CV carburetor. Although it had its defect, without coming equipped with an accelerator pump, they were able to overcome some of the issues with that particular carburetor in '88 by making available a special needle that went into the venturi or the mouth of the carburetor. In 1989, they introduced the CV carburetor that you see here with the fully functional accelerator pump. Now, constant velocity means as the air flows into the opening of the carburetor, it allows the slide to lift. By allowing the slide to lift, the needle that's down into the emulsion tube allows fuel to climb the emulsion tube, atomize, and exit the carburetor into the engine. And even though there is still a butterfly behind what's known as the vacuum slide, this carburetor works basically flawlessly. Most people were able to take these carburetors from 1989 right to 2006 on the Twin Cam engines, obviously, '89s were Evolution. They ran right to '06 on the Twin Cams. You were able to jet 'em, you were able to upgrade 'em, make 'em fit a number of performance applications, from custom air cleaners to wide open free-flowing exhausts. The carburetor is basic. There is a number of components must work correctly, must be installed in the correct direction. They're very easy to jet, they're very easy to maintain. Typically, when these carburetors stop working correctly, they're telling you they need to be rebuilt. CV Performance is making an extensive line of products to not only rebuild, but upgrade the CV carburetor. Whether it's an idle mixture screw adjustment, it's an upgraded fully brass fuel inlet elbow, which when adapted with a 5/16ths fuel line can offer 40% more fuel to the float bowl. This stock plastic elbow had a couple of issues. One, the plastic became brittle and hard, they would have a tendency to break if you happened to over-tighten the clamp. And a very hard 90-degree turn in was restricted to flow, especially when you're getting into a bigger-inch engine and fuel requirements, fuel demands greatly increased. They make a number of high-quality stainless steel fasteners not only to attach the float bowl to the carburetor, but also the accelerator pump body to the base of the carburetor. All of their rubber components, from the manifold spigot seal to the accelerator pump diaphragm, right on down to the boot that covers the accelerator pump arm itself, are all made of high-quality rubber. You don't need to worry about today's fuels causing any type of rubber degradation or premature failure. When it comes to the CV carburetor, best advice I can offer you is to make yourself educated. Always work in small increments. Don't go into a carburetor, for example, that as a #46 slow jet, and increase it by any more than one size per time. What you need to do, like anything else, know where you start and know where you finish. That way, if your finished result isn't acceptable, you can always revert, return back to the starting point. Again, CV Performance, their website is just a plethora of knowledge pertaining to the CV carburetor. And this carburetor still has its place. Believe me, there are a lot of carbureted motorcycles out there. There probably isn't as many these days as there is true fuel injection, but what's out there carbureted has to be maintained and serviced just the same. And when it comes to correct products to keep your carburetor working correctly or upgrade it for any type of performance application, CV Performance is the best source for this type of component.