Width matters - more width is more drag. Overall diameter doesn't matter much; aspect ratio and tire construction are more important.- tire size, does it make much of a difference to change circumference / width
(To like i3, 155 wide, 220cm circumference).
I know it does with an ICE, so I'm guessing YES
Not a single specific speed range applying to all motors in general - that would make no physical sense. For any given motor there is an optimal combination of speed and load, with all other combinations less efficient. Just do a web search for something like "Nissan Leaf motor efficiency map" to see examples (showing best efficiency in roughly the middle of the speed range and at the full load allowed by the controller), since the Leaf is well studied and reported. Other motors will have other optimal points.- is there an efficient rev range in electric motors?
Why limit the choice to NetGain, a company which doesn't make any modern motors? The HyPer9, which they buy from Dana TM4, is the only modern motor that they sell.- most efficient air / water cooled Netgain?
HyPer9 is available in Europe.
Nearly any motor will be sold with a controller, or one or more controllers will be suggested as suitable matches.- any other motors you would advise? Preferably available with controller as pack
For efficiency? I suggest doing some searching to see if you can find an objective measurement of transmission efficiency which shows any difference at all between straight-cut and helical gears.- gearbox with straight cut gears worth the investment?
Compared to front wheel drive, rear wheel drive has handling advantages, and of course a traction advantage in rear-heavy vehicles. Neither is inherently more efficient.- is rwd more efficient in EV's ( enough to convert, because I could)?
If you've swallowed that nonsense, you need to forget anything you've heard about Tesla from Tesla fanatics, and instead look at objective facts.- I understand Tesla units are the most efficient...
No, no modern EV has an air-cooled motor.And they are also aircooled?
No. There is no inherently best voltage for efficiency. You need to look at specific motors to meet your needs, and the what voltage they would need to operate properly.- is a 130v motor more/less efficient than a 400v with the same battery pack (say 16 cells, differently connected of course )
But motor voltages as low as 130 V are just to make projects easier for small industrial vehicles and DIY conversions - no production EV or even hybrid would go that low, just because they couldn't get adequate motor performance at that voltage.
What do you mean by "kWh?" in this question? A panel is limited in the power it can deliver; there is no energy value associated with a panel. And it's rarely worth the cost to mount a solar panel on a vehicle.- solar panels on car efficient? kWh?