RAD - Equal Air Seems Fair

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-RAD-

Equal Air Seems Fair

The Question - What about the RAD valve from Boyesen, is it worth it for a Banshee? What about a boost bottle - does it help?

The Response - The RAD valve works best on engines that have the carburetor angled (either to the right of to the left) and are attached by a curved rubber intake boot. An engine like a TRX250R or a Blaster has its carburetor angled to the left to make clearance for the rear shock. These engines can benefit a great deal from such a design. The idea behind the RAD is to even out the amount of mixture that will pass through the previously designed (symetrical) reed cage openings. This would (be more likely to) allow both sides of the transfer port tunnels to receive the same amount of mixture. A look inside the TRX250R RAD valve reed cage shows four different sized tunnels.

The Banshee already has its carburetors mounted directly in front of the reed cages with no offest what so ever - therefore there is little to gain from the RAD concept - and that cage shows no such changes. Unless there is a significant increase in the amount of reed petal surface of a replacement reed cage - little will be gained. The Banshee comes with a small, poorly designed reed cage, and I have seen few aftermarket designs that can improve on it that much do to the lack of space required to do the job properly.

The boost bottle improves throttle responce and fuel mileage at very low RPM settings. For the person who drives the Banshee at 3000 - 4000 RPM - buy one.

Rick

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Equal Air Seems Fair
The Question - What about the RAD valve from Boyesen, is it worth it for a Banshee? What about a boost bottle - does it help?
The Response - The RAD valve works best on engines that have the carburetor angled (either to the right of to the left) and are attached by a curved rubber intake boot. An engine like a TRX250R or a Blaster has its carburetor angled to the left to make clearance for the rear shock. These engines can benefit a great deal from such a design. The idea behind the RAD is to even out the amount of mixture that will pass through the previously designed (symetrical) reed cage openings. This would (be more likely to) allow both sides of the transfer port tunnels to receive the same amount of mixture. A look inside the TRX250R RAD valve reed cage shows four different sized tunnels. The Banshee already has its carburetors mounted directly in front of the reed cages with no offest what so ever - therefore there is little to gain from the RAD concept - and that cage shows no such changes. Unless there is a significant increase in the amount of reed petal surface of a replacement reed cage - little will be gained. The Banshee comes with a small, poorly designed reed cage, and I have seen few aftermarket designs that can improve on it that much do to the lack of space required to do the job properly. The boost bottle improves throttle responce and fuel mileage at very low RPM settings. For the person who drives the Banshee at 3000 - 4000 RPM - buy one. Rick