A lot of people on here had either had a car dyno'd, or know someone who has had a car dyno'd. Those cars are mainly turbo'd, supercharged or spraying. Not many "bolt-on modified" cars hop on the dyno to actually get tuned. Most will just make pulls to get a horsepower/torque number.

Those of us with FI motorcycles were blessed with the invention of the Dynojet Power Commander. This makes it very easy to control air/fuel mixture and ignition timing, depending on what model you have.

At SP, we do a ton of mapping for Harley-Davidson bikes......but not nearly as many sportbikes. What I've come to notice, is that most sportbike riders don't want to lay down the $399 for a custom map. The same people that will pay $1000+ for an exhaust, and $300 for a power commander, wont pay one-third of that to make it all work together.

Here is a graph of a bike I just did.....my bike. It is a 2006 Suzuki GSXR 1000. Mods are a full Akrapovic exhaust, PC3 USB and a K&N air filter. This is a basic bolt-on bike.

Sorry, I don't have a scanner, so I had to take pictures.....

The 3 graphs represent the following:

The BLUE graph is the bike with no mapping done at all.

The RED graph is the bike mapped with the downloadable map from Dynojet for my application.

The GREEN graph is the bike with a custom map.

As you can see, the custom mapping gained an additional 2.5 HP and almost 2 additional LB/FT of torque over a generic map(4 and 3 respectively over no map at all). That is a substantial gain not adding any performance parts. Simply making what you have work together. It is also right on par with what typical performance parts (full exhaust, slip ons, PC) add as far as dollars per horsepower.

Apart from that, a custom map can make your bike run smoother due to elimination or "hills" and "valleys" in your HP and TQ curves.