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RedDevil · 11-11-2016, 06:03 AM

I'll recalculate in metric.
300 lbs is almost 150 kg,
65 mph is about 30 meter per second.

Rotational mass on the outside of the wheel takes twice the effort to speed up (one time for motion relative to the vehicle, one for absolute average movement).
The power needed to reach a speed is the quadrate of that speed in m/s times the mass, divided by 2.

It takes 150 * 2 * (30 * 30 / 2) = 135.000 Joules to get those wheels up to speed.
One hp is about 740 Joules per second (Watt), times 65 is about 50 kiloWatt

If all this is correct the mass of your wheels add 2.7 seconds to the time needed to speed up to 65 mph using 65 hp.
It would take one second at 180 hp, it would take 3 minutes on one horse.

Why would you want to go that fast?

11-11-2016, 06:03 AM	#2 (permalink)
RedDevil Master EcoWalker Join Date: Dec 2012 Location: Nieuwegein, the Netherlands Posts: 4,004 Red Devil - '11 Honda Insight Elegance Team Honda 90 day: 55.9 mpg (US) Thanks: 1,715 Thanked 2,251 Times in 1,458 Posts	I'll recalculate in metric. 300 lbs is almost 150 kg, 65 mph is about 30 meter per second. Rotational mass on the outside of the wheel takes twice the effort to speed up (one time for motion relative to the vehicle, one for absolute average movement). The power needed to reach a speed is the quadrate of that speed in m/s times the mass, divided by 2. It takes 150 * 2 * (30 * 30 / 2) = 135.000 Joules to get those wheels up to speed. One hp is about 740 Joules per second (Watt), times 65 is about 50 kiloWatt If all this is correct the mass of your wheels add 2.7 seconds to the time needed to speed up to 65 mph using 65 hp. It would take one second at 180 hp, it would take 3 minutes on one horse. Why would you want to go that fast? __________________ 2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut. lifetime FE over 0.2 Gigameter or 0.13 Megamile. For confirmation go to people just like you. For education go to people unlike yourself. Last edited by RedDevil; 11-11-2016 at 06:59 AM..