Evaluating Performance Gains


Ride a stock V-twin motorcycle, and then ride a stock V-twin motorcycle with a Thomson Supercharger installed. The gains are truly undeniable. The motorcycle industry has become greatly reliant on dyno charts to show performance gains for anything from, spark plugs to a complete big inch engine. Unfortunately most consumers may become confused looking at all these charts, not knowing what the data is showing, or how the improvements could benefit themselves. For simplicity sake, a dyno printout plots overall horsepower and torque values. Dynos measure torque, not horsepower. Horsepower is mathematically calculated using the measured torque values.


Most consumers, and tuners alike, mistakenly believe that the peak value of these numbers is the goal for a strong performing engine. However, peak numbers mean very little, other than maybe during a horsepower shootout. For your engine to be fast, the goal is to increase the area under the horsepower and torque curves as much as possible in the engines usable rpm range. The location where peak torque occurs is vital, because this determines the shape and location of the horsepower curve. When choosing any performance part, the objective is to maximize torque within the rpm range of your particular riding style. The flatter and higher the torque curve is in that range, the better.





Dyno Tuning Variables


It is our opinion that a dyno is to be used as a tool. Not a marketing tool, or a bragging tool, just a tuning tool. Using a dyno as a tuning tool with our supercharger system can be both confusing and misleading. Why?……. Because our supercharger is load reliant……meaning…..the blower will only produce boost when a significant load, and or, significant throttle opening is present……..Why?………….The supercharger moves air……….it can’t move air if it can’t get any (small Throttle openings / no load).  A traditional Inertia dyno test, or a lightly loaded dyno test, will only give you a small glimpse of the performance capabilities of our system.


Why do dyno readings seem inconsistent when comparing dyno charts posted in magazine articles,  on websites,  and in other advertisements?   Most important in any test situation, whether a product comparison,  or a tuning test,  is performing all tests under consistent,  identical conditions,  and making only 1 change at a time.

Some Testing Variables That Effect Readings


1- Dyno Type used

2- Dyno Data Smoothing

3- Tire Pressure

4- Loading

5- Gear Selection

6- Fuel Octane

7- Tuning

8- Air Temperature

9- Engine Condition

10- Engine Temperature

11- Gearing

12- Dyno Accuracy (Calibration)

13- Dyno Operator Variables

14- Clutch Condition/Type

15- Tire Condition

etc, etc, etc……….the list goes on