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The Boyesen Power X-Wing is the simplest, most economic way to maximize the power and efficiency of your HD's intake. See the benefits of releasing the pure and simple potential trapped in your bikes engine.

» Acceleration gains from idle to wide-open throttle
» Max power gains up to 4Hp. Dyno tested
» Max torque gains up to 5ft. lbs. Dyno tested
» Compliments popular airfilter upgrades
» Smoother, broader power
» Up to an 8% MPG improvement
» Consistantly ride in a higher gear
» Dramatic improvement in ride-ability
» Simple bolt-on, no modifications needed

The Cause and Effect of the POWER X-WING

In order to understand the benefits of the Power X-Wing, you need to be aware of the importance of air velocity and how it relates to your engine’s power. As air velocity (speed) increases the more viscous (dense) it becomes, causing the air to display characteristics which are more like a fluid. The effective air velocity creates an action known as fuel shearing, splitting the droplets of fuel into a finer gas like mist. With the two different substances becoming more like one another, we achieve a superior homogenous air/fuel mixture. We know that with a uniform saturation of air and fuel, a superior and more efficient combustion will result.

Lets talk about Volumetric Efficiency: a measure of how well an engine breathes. Usually expressed as a percentage; For example if an engine is said to be 85% volumetric efficient (at a specific rpm), then it is ingesting a volume of air that is 85% of what it would achieve if the cylinder were allowed to fill completely by the force of atmospheric pressure. We should remember the importance of volumetric efficiency and its role in an engines ability to produce torque. In fact, volumetric efficiency and torque output are virtually the same as it relates to RPM.

Simply put, air and the velocity it can generate is the most important part of the performance equation.

The Power X-Wing increases air speed (velocity) at all throttle settings. It does this by directing what comes through the air filter into the carb/throttle body. That air becomes very turbulent when it passes through the filter and therefore the blades of the Power X-Wing extend out into the filter space to guide and direct what comes towards the bell of the carb/throttle body. As this air is guided into the throat and bore, the Power X-Wing starts to straighten the air through its four channels and walls, effectively minimizing turbulence. As the incoming air becomes less turbulent, the molecules are calmed down and take up less volume. Therefore they come closer together, producing a denser charge. This charge also increases in velocity, because stable and less turbulent air has less friction when it moves at high speed. Furthermore, the air, which is now more laminar (smooth) in flow, is better able to pass the butterfly and shaft barrier, which especially has the effect of improving velocity going into the engine.

This is especially true at part throttle, because then the four channels become more like individual velocity stacks. These stacks at smaller throttle openings create a greater proportional increase in velocity when compared to standard.

Now that we realize these kinds of gains in velocity, the cylinders are filled more freely. With high velocity and dense laminar flow, the air increases its ability to shear the fuel droplets and therefore improve atomization. By this method the combustion process becomes more efficient, complete and effective, producing better torque and power. Even better fuel economy. The improved and increased performance has been demonstrated on the dyno and by radar tests.

Less obvious to the reader are the kinetic energy gains in a running engine. Because of the superior cylinder filling efficiency, less drag is sensed by the crank as the intake stroke happens. The result of this phenomenon allows the crank to gain more momentum to turn faster for smoother power delivery, better throttle response and stronger acceleration.

Now picture a motorcycle being driven down the highway, the throttle being held partially open to maintain a constant speed and rpm. At this constant rate one could measure the volumetric efficiency (how the engine breaths). For example, at a given throttle position, the engine will produce road torque to maintain the motorcycle speed for the driving conditions. Now, picture the same conditions, except we installed a Power X-Wing, which changes the engines ability to improve net airflow. We induced a modification that creates effective velocity and improves volumetric efficiency. Because of this improvement, the engine will require less throttle opening to produce the torque required to maintain the same motorcycle, at the same speed, for the same driving conditions. We have created a condition that leads to a more effective combustion.

Having said all this, the Power X-Wing has the ability to create an effective air velocity that initiates a homogenous air/fuel mixture into the intake tract. This produces a more volumetric efficient engine for an increase in torque, horsepower, throttle response, acceleration, and fuel economy.

I installed both the Power X-Wing and TwinShot at the same time, very easy to do, first class product to install. I originally gave these products a try because I believe in the stock CV carb. I have an '03 WG, stock 88, air filter, Vance & Hines jet kit, Krome Werks slip-ons and Screaming Eagle plugs. I will let you know this is the best mod i've done to any bike in some time. Easier starting...cold or warm. Made the throttle response much, much better and as far as riding, just an unbelievable change to a carbureted bike. This thing works awesome, definately carry a gear higher like advertised, no bucking or coughing in 5th geat at low RPMs. I can tell you it was money well spent, and it made my Harley run better than I thought a Harley could. Two thumbs up for sure! - V-Twin Forums July '11

I recently purchased the X Wing for both my bikes, 2004 Road king and a 2007 Dyna Low Rider. This item has me flabbergasted. The difference in both bikes is almost a dream. Low end torque is amazing on the Road king and on the Dyna. Mid range has a very noticeable improvement on both bikes and top end has improved by at least 15% (estimated). I just want you guys to know that this item is very well worth the money and was a pleasure to install. It took longer to get the tools out and get setup than to install it. I am fifty years old and as a younger guy I always used your reeds in my dirt bikes and was always satisfied. Now with this product I am overly satisfied. All Harley owners should invest in this part. To all, it will make your bike feel as though you did some major work to it and in reality it’s a fifteen minute job that makes a drastic change in total performance to your machines. Buy one today!!! Thanks Boyesen another great job!!!!!!!!! - Mark A. Feb. ‘11

I installed your POWER X-WING in my ole shovel today. She has S&S heads, Andrews B-Grind cam, high compression pistons and S&S Super E carb. I can't believe what a difference it made! Crisper response and more pull throughout! Thanks for a great product! - Dave R. Nov.'09

I've always been skeptical about instant HP gains with bolt-ons, but I can attest to the Boyesen Power X-Wing. The reason I bought it was because of the company reputation, previous product use, independent magazine dyno comparisons & regular people testemonials. On top of that they offer a 100% not satisfied guarantee full refund! I bought the X-Wing and it did everything they advertised and more!! Hell, if it had done 1/2 of advertised I would have been happy! Just to make sure that I was not just wanting to feel a difference, I took the X-Wing out and had a buddy (that had only ridden my '79 shovelhead once before) ride it for 10-15 min. and had him drive that same route the same way (as in accel / breaking, etc.) and immediately afterward with the X-Wing in. His words were, "Like Night and Day!" I've not gotten a chance to check out the top end power but am sure I'll be happy. No doubt I have gained low & mid range torque, throttle response and complet overall engine smoothness at all RPMs!!! I wish all company's would manufacture and stand behind their products like Boyesen does!!! THANKS!!!!!! - Doug T. in Minnesota Oct. '09

Hello all at Boyesen. Recently I purchased a Power X-Wing for my '05 1200R H.D. I had already made substantial modifications to the CV carb. (All the normal stuff to get the machine breathing better). High flow air filter and less restrictive mufflers as well. I thought, the x-wing might help a little and for 150 bucks (AU), what the heck. If I hadn't experienced the overall improvement first hand, I would find the claims hard to believe. It's a little beauty. Much better starting when cold, even better throttle response from down low. It's like the bike is running really clean, fresh fuel all the time. (The fuel we get here in Australia is crap). But best of all I'm getting at least another 65-75kms (about 40-50 mile) between fills and with only a 13 litre (about 3.4gal) tank, that gets me a whole bunch further down the road. From an environmental perspective, it should be law every HD with a CV carb have an X-Wing fitted. Simply a remarkable product. Thanks. - Hayley Lawton, Echuca. Australia. July '09

I purchased the X-wing for my 2008 Street Glide while at the Gettysburg bike week. Installation was straight forward and easy. I now have over 150 miles with the X-wing installed. Here is what I've noticed: more precise throttle control, more usable power at lower RPM range, smoother running at lower RPM's, increase in gas milage of approx. 3 more miles per gallon. - TomCat July '09

I installed the Power X-Wing on an '08 Heratige and it works great! At first I was skeptical, but after some research I deceided to give it a try. Your product improved the whole power range and gave much crisper throttle response. All in all I am very impressed. - Rob V. June '09

I just installed the X-wing in my 2008 Sportster. It works incredible! Just like it says it would. Very dramatic! Thanks. - Michael A. Feb. '09

I would like to provide some input on the PowerXWing. I installed it on my '07 Harley Ultra Classic. The first thing I noticed was the throttle response and boost in the power spectrum. It is much quicker and the bike is more responsive. I have constantly heard Harley owners complain about the six speed transmission being difficult to deal with and at what speed the sixth gear is used. Well I immediately found with the PowerXWing I could actually shift into sixth at much lower speeds. In fact I can go through all the gears and have a very comfortable ride at 60 mph and be in sixth. The rpm's drop to about 2K. What a difference. All in all the PowerXWing is a welcome addition to my bagger. Thanks for a great product. It certainly lived up to my expectations. - Mark Y. Jan. '09

I received your Power X-Wing the other day, installed it in the carb and took it out for a ride. I could not believe the instant reaction of the engine and the mid-range power. It was awesome. If I did not install this great piece of engineering myself, I would have thought they replaced may carb with a high priced aftermarket. Thanks for rejuvenating my original 1991 FLHTC. - Jiacamo A. Jan '09

Just received the Power X-Wing and I have to say it was money well spent. I wasn't sure what to expect, but after a quick install it made a BIG difference in performance that was noticeable with the first turn of the throttle. The money I spent on your product was well worth it... Thanks. - Steve F. Oct '08

A definate improvement in acceleration throughout the RPM range, most noticable in the low RPM range. Rolling acceleration at any speeds below 80 MPH was noticably improved. Installation, of coarse was very simple and instructions are suitable for any basic mechanic. - A. Miller, Sept '08

I read about your Power X-Wing for Harleys in Thunder Press and thought why not. It was not that expensive and if it didn't work, oh well. Well it works, it works so well that I thought I was riding someone elses '07 Softail. How can something this simple make such a profound difference in torque at the bottom end is beyond anything I could imagine. A winner! - Eric Lee, Sept '08

I was very skeptical until I rode this Sportster. After installation, very impressive throttle response and torque. - Skip - Fullwood Custom Cycles, Aug '08

A very good product, 5 out of 5 for performance and installation. People are kind of skeptical after products like the turbulator, etc. - Todd - 52/52 Performance Tuning, July '08

Just a quick note to say how impressed I am with the Power X-Wing! Installation was very easy, even with a Dougherty PowerVents and a Kuryakin Hypercharger installed on the bike. I noticed the improved performance with the very first startup. I didn't have to choke the engine as much to get the fast idle and the throttle has a definite snap to it that wasn't there before. - Tony G, July '08

I just returned from a 1030mi 3 day trip on my 2006 Harley Deluxe EFI. I had full aftermarket bags (not the little Harley ones), an over full pack on the back rest, and my 120lb girl. The bike ran strong. After installing the X-wing myself (it was simple), there was a noticeable improvement in performance just putting around town, but even more noticeably on this trip. There seems to be much more low end response and acceleration (torque)out of the hole, and the bike also seems to "pull" a lot more at the top end (HP) for passing. I am very pleased with the X-wing for the cost/performance ratio. Very worth while. The bike seems to spit and pop a bit more while decelerating with the aftermarket exhaust that I have as well, which I like. It sounds very cool. I only wish I would have gotten this enhancement for last years trip to the Blue Ridge Mtns. It would have handled the hills much better. Thanks Boyesen! - Adam Muth, July '08

I was at Daytona Biketoberfest and I saw a Boyesen display with a new product (Power X-Wing) that claimed more horsepower. The guys told me how it worked and offered to install it in my 2006 street glide for a test ride. I rolled off a light in first gear and whacked the throttle. My tire started to spin and the bike fish tailed, I went back and laid down the money totally satisfied. The rest of the week I could'nt wait to grab a handful of throttle. - Fred Martucci

A HOME RUN! It makes the bike accelerate so much better. Everybody should have one. - Ron Hilbert

WOW It is unbelievable that this little part can do so much to make my bike run this good! The Power X-Wing even fixed the spitting problem my bike had when I got on the throttle. - Kevin Sousley

After testing: I do not want it taken out! - Heath Wessner

Works Great, more power when you need it! - Roger Snyder

Much more throttle response, more power and torque in the bottom gears - Terry

When I went to pass, the bike just kept accelerating, I did not have to down shift. - Dave Zellers

Feels much better in the lower gears. Accelerates much better than stock. - Mike

I can spin my tire in second gear; I have never spun in second with out the Power X-Wing. I can really feel the power when a passanger is on the back. I like the acceleration out of the turns, I don't have to down shift as much. My bike just runs so much better. - Tim Smith


Q: What is a Power X-Wing?
Q: I thought that when you put something into the flow path of the carburetor/ throttle body it would restrict airflow. Why doesn't the Power X-Wing restrict airflow?
Q: Isn't the Power X-Wing like a Turbulator?
Q: How hard is the Power X-Wing to install?
Q: What kind of performance gains will I see?
Q: Will the Power X-Wing work with aftermarket air filters?
Q: Will the Power X-Wing void my warranty?
Q: Do I need to rejet the carburator?
Q: Do I need to remap with an EFI system?
Q: What is your satisfaction guaranteed?

Q: What is a Power X-Wing?

A: The Power X-Wing is a patented air vane that mounts between the intake (carb or throttle body) and airfilter.

Q: I thought that when you put something into the flow path of the carburetor/ throttle body it would restrict airflow. Why doesn't the Power X-Wing restrict airflow?

A: There seems to be a misunderstanding about the laws of physics and putting something in a carburetor/ throttle body, most people think that this will reduce the bore size and restrict airflow. Probably so, if you evaluate the parts they are referring to. Now if we apply the laws of physics you can clearly see that the assumption of restricting the flow of air by inserting a Power X-Wing into the carburetor/ throttle body is totally false for the following reasons:

1. The wing does not reduce the bore size of a carburetor/ throttle body, because these mechanisms have a butterfly shaft that crosses through the bore of the carburetor/ throttle body which is the determining factor of the true bore size using the following formula: The bore cross- sectional area minus (the diameter of the shaft times the diameter of the bore) equals the actual cross-sectional of the bore. The wings do not change the cross-sectional area of the bore because they are only .030 thick, which is approximately 10% of the shaft diameter.

2. The Power X-Wing wings are parallel to the direction of airflow, unlike other products that have curls and radius fins that protrude into the air path and cause a disturbance in the air stream.

3. Air traveling through an intake wants to swirl as it enters. The carburetor and throttle body butterfly mechanism disturb the swirl and causes a loss of energy that slows down the entering air. The wing directs the air before it enters the bell of the carburetor/ throttle body. Now the air entering the throat of the bore of the carburetor/ throttle body that houses the butterfly, which divides the bore horizontally into two halves parallel to the flow of air will be more laminar across the butterfly. This increase in air speed, starts at the filter and continues past the butterfly, because of the laminar flow the wings created. Now the air on the valve side of the carburetor has increased velocity and can start the undisturbed natural swirling of the intake air to flow into the combustion chamber more freely, which in turns fills the combustion chamber more efficiently which allows the motor to build more torque and horsepower faster.

Q: Isn't the Power X-Wing like a Turbulator?

A: Absolutely not. Where the Turbulator and Turbulator like products intentionally swirl in-coming air, the patented Power X-Wing is designed to eliminate air turbulance. The streamlined airflow will increase air speed and improve intake density for added efficiency and power.

Q: How difficult is the Power X-Wing to install?

A: Not difficult at all. With standard tools you can expect approx. a 30 min job. No modifications or adjustments are needed.


Q: What kind of performance gains will I see?

A: Depending on modifications you can expect up to 4HP and 5ft.lbs of torque gained. Additionally, fuel milage is increased by 8% while ride ability is greatly improved.


Q: Will the Power X- Wing work with aftermarket airfilters?

A: Yes, the Power X-Wing will compliment popular air filter upgrade.


Q: Will the Power X-Wing void my warranty?

A: No, installing the Power X-Wing will not void manufacturers warranty.


Q: Do I need to rejet my carburator?

A: No, rejetting is not required unless you have an improperly tuned setup.


Q: Do I need to remap with an EFI system?

A: No, the Power X-Wing does not require remapping.


Q: What is your satisfaction guarantee?

A: The Boyesen satisfaction guarantee ensures that if you are not 100% satisfied with your purchase of any Boyesen product, you can return it for a full and complete refund.



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