Motorcycle Repair: science fair project, laser temp, compact engine

Question
QUESTION: im am in eighth grade and i am doing a science fair project with a 2005 honda cr85r, two stroke, and a 2003 honda cr80r. my question is if i ride each bike for 15 minutes, which exaust pipe will be hotter. i was also wondering if there was any cautions or hints you coukd let me know. Thank you so much

ANSWER: Chance,This isnt really a fair question.The bikes wont be ridden exactly alike. If one of the bikes is an expert model the tires and rims are even a different size and ambient temp and humidity could change. Are the pipes stock is the air cleaner stock in each bike they are different years so the engine refinements have changed. Even if I use my laser temp gun on the exhaust after riding and the 80 was hotter,this may not be accurate as you familiarity with the riding course you will take. The second bike may be ridden faster or harder due to the human nature of confidence and how the bikes suspension is set up,sorry..

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QUESTION: Thank you for this helpful information. I was wondering if you thought it would just be easier to let both bikes run for fifteen minutes

Answer
Chance, It may not help your research much how are you going to check temps? Are you going to use a Laser temp gum or a thermometer in the coolant in the radiators. The two strokes were able to run cooler and had a more compact engine but the four strokes had more moving parts and more mass so they tried to keep the temp down to keep from siezing up the cam and valves. You can try the idle but air moving through the radiator will keep them from overheating and engine failure.