This system is different in its' method of adjustment by dealing directly with the fuel injection signal after it leaves the factory ECU. It adjusts fueling without tricking sensors or modifying factory settings which limit the ECU's effectiveness at compensating for changing altitude or weather conditions.

Idle/Cruise: As fuel injection is very efficient, it considers idle and cruise to be virtually identical as far as their A/F ratio requirement goes, so the low speed adjuster (Green Adjustment Screw) can be set similar to an idle mixture screw on a carburetor. As the motorcycle accelerates under light to medium load, the ECU maintains an A/F ratio consistent with its emissions focus, and the TFi box makes slight modifications to that focus based on your drivability requirements.

Midrange: With fuel injection midrange fueling is only relative to fast acceleration at or near full throttle. At certain speeds and loads as the factory ECU makes transitions between cruise and performance A/F ratios. Using the yellow adjustment screw and the RPM select adjustment the TFi box has the ability to select and alter fuel at these points of transition. This effect is similar to the effects that a needle position change and an accelerator pump can have in a carburetor.

Main/Top End: Once the throttle is opened abruptly or an engine RPM/load is achieved that demands a performance bias A/F ratio, the main fuel adjuster can come into play. (Red Adjustment Screw) Similar to carburetion, air filters, race exhaust, cams, etc. can effect the fuel requirements in the performance range. The main fuel adjuster can compensate for these types of modifications just like changing a main jet in a carburetor.

The best way to optimise your TFi is to match the installation of your TFi with a professionally executed Dyno tune. Tornado will be delighted to prove to you that the TFi can make substantial additional power while improving smoothness and throttle response across the entire rev range.

The TFi is also the perfect partner for a performance exhaust system and intake modifications. The TFi permits accurate adjustment to the exact needs of the engine and modifications. This means that TFi improves the investment that you make in your performance parts.

Case Study 1 - On a recent TFi installation on a Suzuki DL650 with a Tornado exhaust, the power was increased from 61BHP at 9,000 RPM to 69.2BHP at 8,000 RPM. This is an increase of 13.5%. More significant is that peak power is now at 1,000 RPM lower. The engine now makes more than the original peak from 7,000 to 10,000 RPM. Power is increased over standard at all engine speeds. The motorcycle is noticeably faster and smoother with no low speed lurching.