I recently upgraded my 03 EG classic by doing a stage 2 with 510 SS cams. I added a pc3 and had a good builder dyno and map the bike. My issue is I thought I would get a little better fuel milage. IM getting around 36 in town and 40 on the highway when running between 65-70 mph. My question is can one plug in a computer and tweak the map in certain areas without messing up the entire 250.00 dyno job.

 

Yes, first save a copy of the current dyno on your laptop then go ahead and tweak what you want to, if you f it up you can always reload the map you saved on your puter...I have the same set up as you and can tell you I get roughly the same gas mileage as you, I'm not to concerned about the mileage because my bike runs strong. If you lean it out to much you're going to run hotter. What kind of gas mileage were you expecting? If you want more take it back to the tech and have him lean it out a bit for you, he should do it at no charge, at least my indy did anyway.