i recently replaced pipes with vance and hines on my 1996 HD Road King fuel inj=and lost power, was told the v&h pipes were good but needed adjustment on carb (chip?) and free flow airfilter-any suggestions or is this just a sell ?
Others on the forum will give you a more informative answer but this will give you something to ponder...
Think of the pipes as the end of the complete system, which begins with air intake. They all--air intake, fuel supply (carb or efi), engine, and exhaust need to be "harmonized" to get maximum power. The pipes create backpressure, which has a direct effect on fuel mixture. Changing the flow at one end and not the other will throw the entire system out of balance. This is true for either end of the system. So, you've changed the fuel mixture by changing the backpressure in the exhaust. Now you need to make the appropriate adjustments at the intake and then adjust the efi accordingly.
Depending on when the bike was built you may have a real problem.
The early Marelli ECM's (95 and some 96's) were not flashable and can not be used with a Power Commander.
If it is a late 96 ECM you are OK and it's no different from any other Marelli bike.
Don't run this thing lean, you will have problems, the early EFI bikes ran lean to begin with.
If it is a early bike, you might still be able to find one of the old Vance & Hines fuelpacks around but as far as I know they don't make them anymore. Worse comes to worse, they used to have a kit to update the ECM's to the reflashable ones and they used to have higher flow injectors for those bikes.
Find someone that has worked on the specific year EFI bikes, and have them find out exactly what you have, and take it from there.
Scooter, My 96 Ultra had the same problem, V-Thunder a Division of Competition Cams in Memphis makes an injection overdrive module for the 95-96 Fi bikes that works well , Dennis Kirk Catalogue has a good deal of Info on the units. I could really notice the difference two up, no spark knock and much better power at low RPMS.