What causes engine failure?Human error!When is an engine most vulnerable?It depends somewhat on the engine. As a rule, it is when beer is involved with the assembly! (Laughs) But actually, engines are most vulnerable when they are new, at lower RPMs, when heat (atmospheric or internal) is involved, or when they suffer from lack of lubrication. And of course—in racing conditions—when the engines are being stressed to death.Is heat your friend or foe?Both. The engine needs heat to work properly, but at some point heat becomes a four-letter word. It also creates pre-ignition and detonation; it melts pistons, burns valves, blows the tips off spark plugs and robs power. If you think about it, most of the things engine builders do is to manage heat. They do this through ignition timing, valve or port timing, combustion chamber design, managing compression and also by working with carburetion or injection and the exhaust system.What is the biggest misconception about oil?In two-strokes many people believe that oil will lean out the engine—our research never shows that. In fact our research shows that with certain oil designs we can increase horsepower. We have also learned that one oil cannot satisfy all engines. That is why we build 52 different oils. We look at each engine, determine its needs and then design an oil specifically for it. That's one of the reasons we have such great success.Where do people go wrong with tuning?They get too aggressive. A rich engine and a lean engine have very similar responses, and it takes many years of experience to tell the difference. As you know from working with me, I believe "when in doubt, build it stout." We always add fuel and work from there.Should people learn how to read a spark plug?Yes! But we put less emphasis on the actual spark plug these days. Reading the plug stems from the old V8 engines, where it was difficult to see inside the engine to learn what was going on with it. With two-stroke engines, I prefer to pull the pipe and read the exhaust side of the piston as if it were the plug. In four-stokes, we pull the pipe and study the exhaust carbon or residues. With modern technology, we also use scopes to study the combustion chamber and the valve, and we rely heavily on data acquisition.What is the biggest challenge racing at a place like Bonneville?Boy, where do I start? The weather doesn't change in hours or days—it changes in minutes. Bonneville is not like any other form of racing that we've been involved in. It is a tuner and engine developer's nightmare. There are the temperature extremes, the moisture that sits right off the salt, the salt vapor that goes inside the engines, the atmospheric heat which can go up to 112°, the adjusted altitude, even the overall distance the bikes have to pull. And once you think that you might have it figured out, you wake up the next morning, and the conditions for the record-return run are completely different.What was the purpose of building the turbo-charged Honda CR125R?We had lots of reasons. As far as we were aware nobody has ever successfully built a true single-cylinder turbo-charged two-stroke. We know that there has been success in bigger cylinder engines, but the challenges in a single cylinder were interesting. There was no commercially available turbo for an engine that small; the smallest one we found was for a 250cc motor. So that became an interesting thing to build. Besides building one of very few tiny turbos—possibly the one and only—we had the interest in going for records at Bonneville. Our company has always pushed the envelope and gone where few have gone, because we find that the journey brings us knowledge that we can use on many projects. We thought creating the turbo might bring us closer to developing two-stroke engines with significantly reduced noise and exhaust emissions. In the short amount of time this turbo has run, we've gotten a tremendous amount of information that we never would have learned from any other source.What are your goals with the turbo land speed record machine?I am very interested in continuing its development. We'd like to learn how to take advantage of the amount of horsepower that we've seen it produce. We also feel that this is an important part of the puzzle that will help us to refine two-strokes. The two-stroke engine is the perfect example of efficient combustion. We have "Save The Two-Stroke" t-shirts. I really believe that the two-stroke engine is both the past and the future. It doesn't need to be saved; what it needs is to be developed into the clean, fuel-efficient powerhouse I know it can be.