Thread: Tire efficiency
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Old 08-07-2020, 04:18 PM   #14 (permalink)
aerohead
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rolling resistance

After winning the World Solar Challenge, in 1987, the GM/ Aerovironment team commented that, had they run the entire race on bald tires, their margin of victory due to the superior R-R of the tread-less tires would have way over-shadowed the additional time they would have lost during the race to changing flat tires.The lion's share of R-R had to do with tire squirm of the individual treadblocks. Perhaps at 200-psi, there was virtually zero sidewall flexure, a common source of R-R.
Another reporting, having to do with LRR tires, commented that, the particular tire under discussion, simply lacked 25% of tread depth found in non-LRR tires. Or in other words, one would be paying full-price for a tire which was already 25% worn out.
In the mid-1990s, I called a California Saturn dealer to see about purchasing a set of LRR OEM tires for the EV1. The parts manager implored me not to do it. He said that the compound used was so soft that, tread life would be half what a conventional tire would have, and I'd end up purchasing tires twice as often, and would ultimately regret my decision.
A book on electric car conversion mentioned that, for every application, there would be an optimum inflation pressure, beyond which,no amount of over-inflation would result in reduced R-R.
Exactly what CAR and DRIVER said in another reporting, after doing the experiments at Chrysler Proving Grounds.
Race fans will observe that many racing tires are 'slicks' to begin with.
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Last edited by aerohead; 08-07-2020 at 04:20 PM.. Reason: add data
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