Thunder Products KTM 250SX Quad Flow Torque Wing – Motocross Action Magazine

The Quad Flow Torque Wing was conceived, built, tested and patented by Lonn Peterson at Thunder Products, Inc.

We have worked with Dick Wilk at Dick’s Racing for many years.  He is our California dealer and a great tuner.  Dick brought our product to MotoCross Action Magazine for testing.  The magazine has a policy of giving credit for a product to whoever brings the product in.

We have Quad Flow Torque Wings for most makes and models of off road motorcycles and snowmobiles.  Note: you must know the maker of your carburetor and size (usually in mm).  Once your carburetor is removed, it’s an easy ten minute installation with normal hand tools (no machining required).  Re-jetting is not usually necessary.  The Quad Flow Torque Wing gives the same results on any engine regardless of make or model for $99.00 per carburetor.  EFI models are available for $125.

Patent #9,464,605

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MXA Torque wing photo

WHAT IS IT?  The Quad Flow Torque Wing is an intake-tract winglet for the KTM 250SX two-stroke that changes turbulent airflow into laminar airflow to improve throttle response.

WHAT’S IT COST?  $99.00 each Carbureted or $125.00 EFI

CONTACT? at 320-597-2700 or  at  (916) 722-2373

WHAT STANDS OUT?  Here’s a list of things that stand out with the Thunder Products Quad Flow Torque Wing.

(1)  History.  TPI’s Quad Flow Torque Wing is not the first winglet to be installed in the intake tract to improve air velocity.  You might have heard of Swirl-Up, Power Now, FMF Snap, Tornado, Intake Twister or the Boyesen X-Wing.  All of these ideas focus on realigning the airflow through the carb throat.

(2)  Concept.  Motorcycle engines are air pumps.  Air is drawn in, compressed by force, expanded by the combustion and expelled by the exhaust.  Contrary to popular belief, fuel does not explode in the combustion chamber.  Instead, the engine processes air, mixes it with fuel and burns the fuel mixture in a controlled manner to expand the air, which in turn pushes the piston downward to draw more air in.  Once you accept that an internal combustion engine is an air pump, you can begin to understand how important the transition of air through the system is.

(3)  Winglet theory.  Intake-tract winglets work like an airplane wing.  They take tumbled air and straighten it out.  Their goal is to achieve laminar flow.  Laminar flow is the smooth, uninterrupted flow of air over the contour of the wing.  The Quad Flow Torque Wing is designed to reduce drag at the air’s boundary layer, reduce surface-friction drag, equalize the pressure gradient and increase air velocity.

(4)  Differences.   Virtually every intake winglet is different.  Some, like the FMF Snap, mount in the air boot’s velocity stack.  Some, like Power Now, mount in the bell of the carb, and some, like the Boyesen X-Wing, extend deep into the carb’s venturi.  The Thunder Products Quad Flow Torque Wing is unique in that it mounts on the cylinder side of the carb’s venturi instead of the airbox side.  Why?  Because it does not want to split the airflow at the fuel nozzle or disrupt the atomizing process at the source.  Instead, the Thunder Products Quad Flow straightens out the air as it exits the carb.  Additionally, it protrudes into the reed-valve area to keep velocity high and eliminate back-pressure turbulance from the flapping reed valves.

(5)  Performance.  Every test rider felt increased throttle response at low rpm, a smoother transition from the low end to the midrange, and a more flexible powerband across the range.  Power take-up felt crisper, and, best of all, the dips in the power curve were ironed out.  The benefit of increasing air velocity is that more air carries more fuel, which results in more effective combustion.  It is a win-win.

(6)  Installation.  You can purchase from Thunder Products or send your carburetor to Dick’s Racing to have some minor machining done to fit the winglet into the front side of the carb throat.

WHAT’S THE SQUAWK?  You can send your carburetor to Dick’s Racing to have some minor machining done to fit the winglet into the front side of the carb throat.  They can be installed at home in about 10 to 15 minutes.

Patent #9,464,605

MXA Torque Wing stars

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