When it comes to late-model motorcycles, fuel-injection systems are heads and shoulders above carburetor models of the past, as far as efficiency and power, but the associated complex electronic engine-management systems, can be confusing to do-it-youselfers used to carbureted engines. But the reality is that these new systems are not that dificult to master — with some guidance, of course, and once you've done so, tuning possibilities are endless. In How to Tune and Modify Motorcycle Engine Management Systems, Tracy Martin covers a modern bike's engine control system thoroughly, and tells you how to extract the most out of your machine. Topics covered include:

• How fuel injection works
• Aftermarket fuel injection systems
• Open- and closed-loop EFI systems
• Fuel injection products and services
• How to get more power from your motorcycle engine
• Diagnostic tools
• Electronic throttle control
• Knock control system
• Modern fuels
• ...and more.

Book Excerpt: How to Tune and Modify Motorcycle Engine Management Systems INTRODUCTION TO MOTORCYCLE ELECTRONIC FUEL INJECTION

WHAT HAPPENED TO CARBURETORS? Carburetors have supplied fuel to motorcycle engines since the beginning. Harley-Davidson's first motorcycle used a simple form of carburetor in 1903 and continued to use carburetor technology exclusively on their motorcycles up until 1995 - some 92 years later. Other motorcycle manufacturers also used carburetors up until the 1990s. At first glance, one would think that almost a century of use would seem to be a good reason to keep this technology in place, but government standards for emissions have changed considerably in the last 30 years. Thus, motorcycle manufacturers had to change their technology to comply with the times. In 1974, the Environment Protection Agency (EPA) enacted the first federal emissions requirements for on-highway motorcycles. These were based on emission standards from the state of California, always on the cutting edge of keeping clean the air we breathe. Initially, the EPA wanted to place controls for exhaust and crankcase emissions for some 1978 and 1979 motorcycles and all new motorcycles starting in 1980. Specifically, engine exhaust gases, including hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx), would be limited. There have never been any federal standards for evaporative emissions (EVAR) from motorcycles, but that was not the case in California, a state that often requires all types of emissions be limited beyond and above federal standards. The 1980 standards finally adopted were more lenient than those that were originally proposed. They remained in effect until 2003, when California opted for a two-tiered approach with new Tier 1 and Tier 2 standards taking effect in 2004 and 2008, respectively.

Subject: Transportation: Motorcycles: DIY: Tuning and modifying motorcycle engine management systems for max performance. ISBN-10: 0760340730 | ISBN-13: 9780760340738 | Motorbooks 149691