Ok ... pardon me for "gearing in" ... but "
inspiration" is not giving me the proper "inspired drive" to satisfaction ...
I would agree that direct drive is the most efficient and simplistic ... but you need a REDUCTION gear. Let's try some simple geometry and 'rithmetic with a motor directly driving the wheels:
Assume at 125 mph your motor turns 14,000rpm. Meaning your car travels 125 miles or 125*5,280 feet in one hour, or 125*5,280/60 feet per minute. Since your drive wheels are thus traveling 11,000 feet in one minute while the 14,000 revolutions happen, each revolution is 0.79 feet. This would match the circumference of your drive wheel, or 12*0.79 measured in inches or an equivalent 12*0.79/PI inches DIAMETER.
Sorry but I would prefer not to run my Tesla Roadster on 3.0 inch wheels which spin at 14k rpm.
I would prefer a final drive ratio of .... oh say ... hmmm ... what would be a nice number ... how about 8.32 ? That would allow me to drive a
single-speed gear reduction
transmission on wheels with 8.32*3.0 = 24.96 inches diameter. I think an 17" wheel with Yokohama 225/45R17 tires might just work out
(45% * 225 mm * 2 converted to inches plus the wheel diameter).
Did I miss
inspiration's point and am I way off subject ?
(Notes: 1) No insults intended; 2) my cursory search did not find the actual final gear ratio for the Tesla Roadster.)