question - too folks with cycle anaylst how much power do you draw?

[bike4life]

Maybe a small, one wheeled trailer generator with huge cables going to the ebike controller? 4500 watts could be fun

I think for like 700 dollars or 800 you can go 10kw on ebay... 10kw ebike unlimited range. the coolest ebike though would be like a rail ebike that could tap into the subways 600V DC... could really draw infinite power and infinite speed... probably go 600mph

 

[87Octane]

why would you say 2.5kw for sustain? I put in a bicycle wattage calculator and came up with 1600w for 40mph.

The calculator I used also came up with ~1600w but the reference point was a road bike using the tops.

What bike are you using? Is it a mtn bike or cruiser? If so, remember those bikes are more upright (with wider handlebar hand positioning) than a road bike using the handlebar tops.

 

[87Octane]

The reason I think this ebike could do 40 is cause the engine in the genny is basically a clone of the 79cc predator 3hp, and when those go in bikes they go idk, 40mph, and the inverter and switchmode is 90% efficient...

Don't forget to factor in the efficiency of the electric motor itself.

So maximum power of generator (3 hp) x .9 (for inverter efficiency) x whatever the efficiency of electric motor happens to be (I'll assume 80% if optimized for the target speed) = 2.16 hp

 

[87Octane]

it really depends on the efficiency of your tires and aero. i would say for a normal mountain bike its going to be like 2.5kW for 40 mph sustain

This calculator is showing 2500 watts for a 6' 250 lb rider on a mtn bike for 40 mph @ sea level:

Bicycle Speed (Velocity) And Power Calculator

Bicycle Speed (Velocity) And Power Calculator, comparing different kinds of bicycles

kreuzotter.de

Lowering the height and weight of rider helps but the power output still ends up being over 2000 watts @ sea level in the majority of cases. (e.g. a rider 5'6" tall and 132 lbs needs 2000 watts.)

 

[87Octane]

For a roadster bicycle:

Roadster (bicycle) - Wikipedia

en.wikipedia.org

Which is very similar to a beach cruiser in terms of seat tube angle and handlebar placement power for a 6' 250 lb man jumps to 3250 watts for 40 mph @ Sea level.

P.S. 5'6" 132 lb rider needs 2595 watts for 40 mph @ sea level.