You are mixing things that are not mutually exclusive.

Both gasoline and diesel engines (as well as other IC engines) can be either two-stroke or four-stroke). All four combinations have optimal operating speeds, but can work over a wide range of speeds.

The big motivation for locomotives using electric drives is the need to produce high torque at essentially zero rotational speed and do so for an extended period of time. Electric motors can be designed to do this very efficiently and robustly. Engines need transmissions and, for zero speed torque, friction clutches or fluid power couplings. For the power output that a locomotive needs, these would be huge, expensive, inefficient, and maintenance intensive.

Yes, an electric motor turning at a slow speed can produce tremendous torque and very little torque at high speed. It is the exact opposite for the ICE. I don't know if they are still running in Seattle, Washington State, but some time ago there were overhead-electric powered buses there which worked very well for climbing the hilly streets.

 

I don't really have a good place to charge batteries, and the price of good batteries that can handle the charge cycles are expensive, how could one control a brushless dc motor off a continuous 48 volt 1000w power supply.

Running a BLDC motor controller off a 48 volt battery is common, and for variable speed it works quite well. But the controller must be designed for variable speed control.

 

The TS has not replied nor made any other posts since April 15.
Like other thread starters, when asked to explain the logic behind their ideas, they simply bail out.

 

The TS has not replied nor made any other posts since April 15.
Like other thread starters, when asked to explain the logic behind their ideas, they simply bail out.

For whatever reason he liked the idea of a bike propelled by an electric motor, but didn't want to power it by means of a battery because the required battery would be expensive and he wouldn't be able to find a place to charge the battery.

 

Consider that petroleum fuel IS more available than charging stations, and more competitively priced as well, there are benefits. So it might work out very well, a bit like the hybrid EVs.