How do you adjust idle for heritage classic harley Davidson 2008 model?

Answer 1

Plain and simply you can't. The Delphi fuel injected Harley models do not have an adjustable idle. A dealer can go in the computer and turn the idle down, but it ends up correcting itself within a couple minutes to the factory specified idle of about 1000-1100 RPM. Even Harley's Screamin' Eagle race tuner won't adjust idle. However Zippers makes a product called the Thundermax. It's a complete ECM control unit that replaces the OEM brain box allowing you to control every aspect of the motorcycle. A great product for performance building or even fine tuning a stock engine. I run one in my 2006 EFI Softail. It lets me change every running aspect of the engine to work with the motor work I have completed on my bike. One feature is the adjustable idle setting. I turned mine down to about 800-850 RPM. It gets a more classic sounding idle out of the bike but, being the Softail models have a balanced engine, they don't sound quite the same as a Dyna, touring or Evolution model. Still a significant improvement over stock. The base module is about $485 and the module with it's own "auto tune" O2 sensors will run you about $899. I suggest the one with the sensors because your bike will dyno tune itself as you ride it. The factory O2 sensors are simple two wire items, where as the thundermax O2 sensors have a 4 or 5 wire sensor which allows more input to the ECM and will allow it to make changes accordingly based on a number of variables (Air temp, exhaust temp, rich/lean, etc.) It's a bit of money just to turn down your idle, but the amount of things that the Thundermax does justifies the purchase. One of my favorite features is the starting circuit. Harley EFI requires the bike turn a couple revolutions to get the fuel injectors going. The Thundermax squirts in a shot of fuel when you turn the ignition on so that when you hit the start button, the engine is already primed. The bike starts almost instantly. Saves a lot of wear on the starter plus you don't get that annoying hiccup here and there. All you need is a laptop or home computer to run the software to program your bike and it's features (that's where you set the idle speed). If you modify the engine at any time, you can go back into the module and make changes or adjustments. Very easy to use even if you aren't computer savvy. The instructions are simple and easy to follow. Hands down the best money I ever spent on my bike, seeing as how it actually makes it run decent.