I find it very hard to believe that this thing works, as in gaining power or saving fuel. Here is my explanation: A 20% fuel savings can be achieved just by a change in driving style. Also, I called the company up and explained my theory of why this product is bogus.
The tornado is placed in the intake tract before the throttle body in just about all applications that I can think of. It is supposed to achieve its fuel savings and power gains by "swirling the air" into the combustion chamber causing a better mixture. However, under normal driving conditions, the throttle blade is almost never WOT, and is most of the time under 60% open. So, the "swirling" that the tornado produces runs into a nice big wall, or in other words, the throttle body plate losing its effect. The representative I talked to had no answer for this, and he couldn't find anyone that did so take that how you want.
On the other hand, there are people who use it and swear that it works, and people who use it and say its crap. Personally, I think its all psycological. When the user installs it and sees a small change in fuel economy (which could be attributed to driving style) he becomes an instant believer.
My opinion is save the $70 and buy a bike for short trips instead
