How to Install a Screaming Eagle Race Tuner

by Richard Rowe

The idea of tuning a Harley Davidson with a computer must have seemed like utter heresy to those used to tuning multiple carburetors with screwdrivers. And, certainly, there is a degree of irony involved in electronically tuning an engine that can trace its design roots back to ancient radial aircraft engines. But Harley's never been one to get left behind, and its own Screamin' Eagle tuning division offers some powerful software designed to get the most out of the best engines the company's ever offered.

Step 1

Turn your computer on, and insert the Screamin' Eagle CD into the drive. The install window should open. click in the "Install Products" button to bring up the install options, and click "Install Data Mode." Follow the on-screen prompts to complete the software installation. You should now see an icon on your desktop for the Screamin' Eagle programming tools. Double-click to open the program.

Step 2

Click the "I Accept" button on the licensing agreement. A window will open that says "Select Tuning Mode File to Load," and you'll see a window with several files ending in "MT2." These are the pre-programmed calibrations created by Screamin' Eagle for your bike. For now, you're just going to select the first pre-programmed "lookup map," which is the basic calibration. Once the file is open, go immediately to the "File" menu in the upper left. Click on it, click on "Save," and save the file under a new name you'll recognize -- "BASIC TUNE 1," for example.

Step 3

Connect the nine-pin serial port connector cable to the matching port on the computer; this is the one you'd normally use for a printer. Connect the other end of the cable to the supplied adapter, and the supplied four-pin to the other end of the adapter. Before proceeding, make sure your bike's ignition key is in the "Off" position, and that you have access to the fuse box. Locations vary -- check your owner's manual.

Step 4

Find the four-pin diagnostic data connector on your bike. Harley puts it in different places on different bikes, most often in the fuse box, but sometimes under the seat. On many bikes, there's a separate four-pin accessory connector under the seat, but it might be a nefarious decoy. Before assuming it's the data connector, open your fuse box and look for the four-pin weather-tight connector plugged into a second connector there. That's the real DLC link. Unplug the link, and plug the other end of the four-pin cable into the connector on the bike. If you cannot find the link, check your owner's manual for the location.

Step 5

Go back to "File" on your computer screen, and click on "Program ECM." The programming window will come up and you'll be prompted to enter a "Comm Port" number. For most computers, this is "Comm 1," indicating the serial port you just connected to. You're now ready to interface with the bike's computer.

Step 6

Turn the ignition key to the "On" position, but don't start the bike. Click the "Get ECM" button on your screen. This will give the Screamin' Eagle program your bike's VIN number, file information and computer ID number. The Screamin' Eagle software is designed so that it can only be used on one bike, so the bike you're using it on now is the only one the program will recognize from now on. If you want to program another bike's computer, Screamin' Eagle will be happy to sell you a second tuner kit.

Step 7

Wait for the program to acknowledge it has your bike's information, then click the "Program ECM Cal" button. The loading status bar will begin its crawl accross the window; do not under any circumstances unplug the cable or disrupt the data transfer, or you could risk scrambling your computer's programming. The transfer will take about one minute. When the procedure is finished, turn the key to the "Off" position, then disconnect the interface cable.

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