Forcewinder Air Cleaners


One of the things we get asked a lot is how well the Forcewinder air cleaner from Force Motor Products works. People like it because it looks cool and offers a lot of knee clearance, but they're skeptical of it's performance because it's got a fairly small filter element and a 90 degree elbow.


Well, we've dyno tested the Forcewinder quite a bit, and this page is to share some of the things we've found. First and foremost, it's performance. The following chart compares it to a Buell "race kit" air cleaner, which uses a large 3" element under an XL style ham can. The testing was done on our 1996 Buell S1, which was nearly stock at the time ... but stock on this bike is nearly 100hp as you can see.



It actually works pretty darn good! Over a certain range, the tuned length of the Forcewinder worked better than no air cleaner at all, which is remarkable. You can see it in the torque curve, too:



We're big fans of the Forcewinders, we sell them and we use them. But at the same time, there's something to be cautious of when using a Forcewinder with a CV carburetor.


The Forcewinder on the left is an older one, the Forcewinder on the right is a newer one. See how the bowl vent area was changed? Well, we've seen entirely too many cases where the new style on the right doesn't do an adequate job of venting the bowl as the rpm's climb. As a result, the motor goes lean and runs poorly.


It's extremely easy to hog this area out with a die grinder or dremel tool and greatly improve the bowl vent. Take a look at the following:



In blue you see how this bike ran with the unmodified new style Forcewinder. In green is how it ran by simply hogging out the float bowl vent area to look like the older style Forcewinder. Here's another real world example:



You can see what a dramatic difference this little modification makes, and you can also see how well the air cleaner performs, approaching the zero-restriction configuration, which is saying quite a bit as an awful lot of the air cleaners on the market don't do this. So we highly recommend Forcewinders for a lot of high performance projects where knee clearance is needed, just be sure to make this modification if you're using it with a CV carburetor. If you're using it with a Mikuni, or with an injected bike, this modification is not needed and does nothing for you.



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