Why don't atv engine builders/owners test the performance benefits of their modifications on a paved dragstrip thus eliminating the subjective conclusions such as it feels faster. Engines typically do not react the same in real world situations as they do on a dyno. Just my thought.

 

Drag strip times are subject to tire traction, driver weight , weather, tire pressure,tire wear, and so on... and often arent repeatable. Read car and driver and road and track, and youll see much different strip times are , for exactly identicle cars.
Dyno is the only way to measure hp, both before and after, that is very accurate and repeatable.