I don't see why they needed to dyno a otherwise stock bike just because of an air filter and muffler change...a good tuner should have been able to get it right without a dyno run. The dyno tune is for more extensive modifications than that.
Now for some info on why a dyno is good for your bike's health
First of all In would like to thank Lancer for all the ideas and parts he has provided me. The information has been invaluable.
Also, Verslagen makes the BEST cam chain tensioner...I have one on my bike and no more cam chain slap....nice and quiet!
The following is taken from a local motorcycle dealer's web site that we are currently negotiating with to do all of our dyno tuning on our Super Thumper engines! They have the ONLY Dynojet 250i dynamometer in all of Vermont.
"A dynamometer enables a technician to precisely record motor performance. As the technician runs the motorcycle, the device records the throttle position, RPM, air-fuel mixture, output gases and power production. Because the testing is in a known, controlled environment the data is more accurate. The testing results are standardized, which enables tests to be compared, facilitating accurate adjustments over time.
Using a dynamometer, a technical can measure the full range of motor performance and can record more data points. When running a motorcycle in a street environment, the motor has little or no time to operate at the extreme low and high ends.
The dynamometer makes it possible to see what is happening inside the motor. It takes what’s happening inside the engine and puts it on a display. People will continually throw stuff at their bike to make it perform better, but don’t really know what it does.
The dynamometer has graphic displays that enable the technician to get visual feedback showing the exact effects of changes. The dynamometer reports air-fuel mixture and cylinder usage (Volumetric Efficiency) by RPM and throttle open percentage. Using this precise data, the technician can make tuning adjustments and immediately get feedback on the change.
When you tune, it’s tuned for the way the bike is running at that time. If you change something – your exhaust or your air cleaner – you change the way the bike is tuned. Even small simple things effect how the bike runs.
The dynamometer is also a good tool for optimizing fuel economy and diagnosing drive train issues.
Using the air-fuel data, the technician can optimize fuel efficiency without running lean. He can troubleshoot drive train issues by using a negative horsepower test, which measures rolling resistance caused by mechanical components.
The dealer's Dyno is a Dynojet 250i dynamometer equipped with an eddy current load unit to create rolling resistance. The unit enables technicians to simulate street riding by creating varying loads. Technicians can setup test ride scenarios or log winter break-in mileage after motor upgrades.
My personal bike is the test mule for ALL of our performance parts and is scheduled to be dyno tuned with a Harley Dyna muffler on it since it seems that is the most common muffler everyone here wants to put on their bike.
IF a deal gets done with them you will see a link to their web site on my web site and I will post results and a dyno chart here when (and IF) the deal is done.
I tried to work a deal with a Harley dealer in New Hampshire and they crapped out...didn't want to work on a non-Harley! Prejudiced don't ya think?