BUY a new Harley and, at the very least, you have to change the air-filter and exhaust to make it run right. You also have to do something about it running too lean (and too hot). Most guys get the upgrades sorted before they pick up their new bike from the dealer with the cost included in the finance. Too easy.
To sort the fuel injection, the Harley dealer will sell you a Screamin Eagle Pro Street Tuner. This is the most expensive Harley part you’ll ever buy that doesn’t actually fit on your bike. It simply gives the Harley tech access to the bike’s ECU, allowing him to flash (load) it with a new map downloaded from the H-D website, or if you want a more accurate tune, to write a new map while running on the dyno.
There are other options, of course, and one of the better ones is the Fuelpak FP3 from Vance & Hines (V&H).
The initial purchase price of the Screamin Eagle Pro Street Tuner and the V&H Fuelpak FP3 is almost identical but that’s where the similarities end.
With the Pro Street Tuner, if you want a new map, the Harley dealer will charge you to install it. And Heaven forbid if you wanted to get your bike dyno-tuned—you’ll be looking at $400—$500 for this once-only service.
On the other hand, if you want a new map from V&H, it’s free to download and install. And the FP3 contains an AutoTune function so you’ll never need to use the dyno again—it basically adjusts fuel settings across the rev range using actual bike sensor readings while you’re riding.
The V&H Fuelpak FP3 plugs into the HD-Lan diagnostic port to interrogate, and re-flash, the ECM. It can only be used on newer H-Ds. It overwrites the original fuel map in the ECM and the device can be removed afterwards.
The Fuelpak FP3 allows you to adjust all the functions in the ECU: speedo calibration using your phone’s GPS; throttle progressivity for fly-by-wire Harleys to give better throttle response; decel pop can be adjusted for open exhausts; you can select different cams; change the rev limit; adjust your idle speed; turn off the active exhaust; and read any trouble codes, etc, in an app on your smart-phone—and who doesn’t love playing with their smart-phone?
V&H has developed an expansive library of maps and you’ll almost certainly find one to suit your bike. Otherwise, you can run the AutoTune feature.
The AutoTune turns off the acceleration and de-acceleration circuits, which makes sense since one adds fuels and the other takes it away, so your bike runs like a bag of shite while it’s operating, especially when it’s cold and/or around town. We did a full day’s ride, used three tank of fuel, on AutoTune, flashed the new map, and bingo! We had our own individual map. Did it make any difference? Probably not. The original map from the V&H website was spot-on to start with. As the FP3 can store up to six maps, it was easy to go back to the original map and re-flash.
We used some Velcro tape under the seat to keep the FP3 in place while we were playing with the AutoTune, and it’s still there—it’s kinda fun being able to open the app on your smart-phone and see how your bike is running.
We loved playing with the V&H FP3 and can honestly say it will revolutionise fuel management for all new Harley-Davidsons.