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Expert: - 8/29/2006


Question
Why does a chain drive system provide a different top speed with 2 different sprocket combinations that have the same ratio at a given RPM? Is the combo with  the larger drive sprocket more effecient? Is the chain being run more efficently(less bend)? This must be a physics thing at the given RPM right?

Answer
Hi Scott:

Not many people have stumped me- -  congratulations !!

My engineering source tells me that chain drives are not real efficient, and those with smaller radii have more friction. Also since they have to run faster to accomoplish the same result, the smaller sprocket system will generate more heat

You might find more answers by consulting with a motorcycle expert.

Good Luck

Dan Liddy
Sarasota, Florida  

Auto Racing

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Dan Liddy

Expertise

Anything concerning race cars, 20 years competition experience, Senior Competition Driver Instructor , car builder, mechanic, welding, fabrication, tuning , engine modifications, set up, suspension design. Specializing in Datsun/Nissan products. Please submit questions about RACE CARS ONLY. No street cars, no video game scenarios Thank you.

Experience

I have been racing for 20 years, I have been the Central Florida SCCA Regional Championship points for 5 years running, and won the championship in my class 2 times. During my first start in the 60's I won many solo awards and the State Championship Drags. I serve as a senior instructor for SCCA, and have taught in Mercedes AMG events at Daytona, and Dodge Viper Days at Sebring International. I have been in the thick of the competition for all of my career. At one time or another I have driven race cars at speeds nearing 195 MPH. It's quite a ride !

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