One of the ways I check pipe temps on my 2-stroke race sleds (snowmobiles) is by using an infrared thermometer, like those that can be purchased inexpensively at Harbor Freight. When tuning two-stroke sleds, pipe temperature (in particular, the tuned pipe center section positioned between the divergent and convergent cones) is crucial in determining CVT clutch calibration, from engagement through full shift. Hot pipe and cool pipe peak horsepower can vary dramatically (up to 1000 rpm) ON THE SAME ACCELERATION RUN. Pipe temp at the holeshot can make or break the acceleration run. The ability to retard ignition timing on the starting line can "put more heat in the pipes, thereby aligning engine's ability to "close the clutch" without "bogging" the engine (much like a stall converter on a car). These little devices have taken much of the guesswork out of tuning two stroke motors. Yes, we also use probe-type pyrometers (EGTs) to constant monitor air/fuel mixtures as well as ignition timing. They are also very helpful in letting you know when you get a load of sub-par (not as-advertised octane) fuel as well.
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