The standard work on the subject! Plenty of practical tips for mechanics! Tuning for beginners and advanced! How sharp should it be? Anyone preparing an engine—whether to seriously modify it or simply to get the best out of the stock machine—cannot avoid the topic of valve timing. The focal point in a four-stroke engine is the camshaft. These range from mild to aggressive, from brand new to refurbished. Des Hammill, an engineer and experienced professional racing engine builder, knows what matters. Here he reveals how to find the right camshaft, how to set up the timing correctly, and how to test it. If your engine still doesn't run after tuning, despite following the tips in this book, then it certainly isn't the camshaft's fault.