Do you have a "Power Commander" for your engine? Or access to a Dynomometer ( Dyno) ? That was actually created as a tuning tool, and not to only display power ratings. Using an exhaust gas anilyser (goes in the tail pipe of the running engine) you can use the readings to see "lean/rich" conditions that can be harmful to engines, and when mixed with your handy laptop and power commander, you can adjust the fuel/air maps (pre-set ratios installed in the software that came with the commander) and you can adjust the spark advance, ect. with the same stuff, at the same time. To answer your question now, you should get a "base" reading to start with once you're able to ride it, and adjust from there. Then add the pipes, 1200cc big bore kit, or other things you do. Which the 883 heads seem to be more efficient, better cooling heads than the 1200's in my experience. That helps performance and longevity of any engine, as I think most of us know. If you change the fuel/air ratio then you will usually have to adjust spark advance. Anytime you change something on your engine that increases or decreases flow through the engine, you should re-map it to prevent damage. What equipment do you have for your sportster engine? Are you going with a high flow air filter system? You should if you go w higher flowing pipes to make the most of its performance. You can sometimes find a qualified tech at swap meets who has his/her own dyno set up and will charge a small fee for 2 dyno runs, and should be able to do the adjustments for you to your liking, but you will need to trailer the bike there to not blow it up. If you have additional info, or questions for me, then feel free to e-mail me personally. Make certain that everything fits (plugs and locations) before you decide to use it. A lot of times, after market, or non-factory parts that were oem on another bike may have fitment issues that need to be addressed. I sincerely hope this helped a fellow rider (or female. IDK you personally, so dnt be offended.) Thanks. Also, you could go on "myspace". Yeah. It can be useful. And search for people who have a custom shop, such as "clarks custom cycles" or schools that teach such classes. They will some times have the students gain experience under the watchful eye of a competent instructor with only a small "lab fee" of $20-$30 plus you buy any parts you need and did not bring.
· 1 decade ago