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Velocity Stack Challenge

Text: Mark Godfrey : Rennfahrer und Ausrichter der Velocity Stack Challenge im US Badwheatherbiker Forum


Velocity stack challenge

This has been a bigger task than I envisaged, but rewarding for me personally in the knowledge and contacts I have made. I have to say a huge THANK YOU to the companies that participated. They took a big risk by giving their equipment to a stranger to test and publish the results.

The Test Participants

2Win Induction Technologies – The SVVS and Vortex Cone
Hillbilly Motors – The FAST System
Adrenalin Moto – The Air Flow System


Let me reiterating why I issued the challenge. There were on numerous boards, ‘discussions” regarding the merits of velocity stack system modifications, claims and counter claims. Somewhere in the personalities involved, the data that potential buyers of the systems wanted got lost and an informed buying decision was not possible.

I’m not in the motor industry. I’m not an induction expert. I’m just a Buell enthusiast and Buell Roadracer and who wants to get the best out of his machine on my available budget. I don’t pretend that I will have answered everyone’s questions in these tests or that some will not find my testing method to their satisfaction. My objective is to simply explore the technology and to present unbiased data to help me and others decide if this is an area to spend their money.

The testes were conducted on a 03 Buell XB9R with just under 2000 miles on the clock. Motor completely stock. Buell Race ECM, Wileyco muffler. I do not know how valid these tests would be for an XB12. I would encourage you to talk to the vendors for your 12’s needs.

In hindsight, there were several different technologies work here in the products tested;
1) air flow conditioning systems (SVVS and Air Flow) ,
2) a free breathing system (FAST),
3) the induction of cool air (FAST)

Results Summary

There is greater detail in each of the individual reports for each system and I would encourage you to read them . All the systems have desirable characteristics that will suit XB owners depending on their riding styles and needs.
In total, 49 dyno runs were completed between the systems tested and the stock rubber stack set up. Dyno heat soak and AFV errors I believe can be eliminated from these results as both these phenomena were witnessed, and their data discarded.

The HP numbers stated below are the nominal gains over the stock system.

SVVS – 3 HP Increase and eliminated the hole in the mid range.
FAST – 6 HP increase and improved the midrange hole
Air Flow – 2 HP increase and improved the midrange hole

My Conclusions

I believe my test have confirmed the following:-

The technology works and has something to for XB owners to consider.
Those of us that were cutting holes in the XB9 air box were onto something.
So-called “cool air induction” does make a difference

My personal thanks to:

Corey James at 2Win Induction Technologies, USA.
Jens at Hillbilly Motors, Germany.
Matt at Adrenelin Moto, UK.

All these guys are knowledgeable about their products and are Buell lovers. All are very approachable and have a lot of information to pass on - Just ask.



SVVS Vortex

Airflow Inlet System

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