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

bike4life

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I plan on buying a 2300w start / 1800w inverter gen...
I have some 120V switchmode power supplies that will convert AC to 96 volts DC at 20 amps... These switchmodes have a 90%+ efficiency.
That power will go to a regular ebike controller...
I am curious whether I should buy a 72v 30 amp switchmode or a 96v DC 20 amp one... hmmm... im thinking 96 cause its faster... i dont care about torque only speed.

So...Curious on whether this will work well, and top speed. I want it to do 50mph... So folks with cycle anaylst, whats the power readings at 40 and 50mph so I can see if my 1800w inverter gen will run it.
 
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 and 4kW peak to get up there. i had a 800w generator integrated. there are like different run modes on the generator. the high mode for max power is just too loud for me imo. i still dont think this is a good idea; there are/was like 1.8kWh of LiFePo4 batteries on BatteryHookup just recently for like $330 brand new. i rather do that than get a generator but give it a try if you want.
 
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 and 4kW peak to get up there. i had a 800w generator integrated. there are like different run modes on the generator. the high mode for max power is just too loud for me imo. i still dont think this is a good idea; there are/was like 1.8kWh of LiFePo4 batteries on BatteryHookup just recently for like $330 brand new. i rather do that than get a generator but give it a try if you want.
why would you say 2.5kw for sustain? I put in a bicycle wattage calculator and came up with 1600w for 40mph. Would you really need 4kW peak to get up there with slower accel.
I remember my old ebike had cheap crappy 18650 cells, which have a C rating of 1... Whe fully charged, it did 35mph...
It had 13 series 4 parallel, so that would be 13 x 4.2 = 54... current = 10 amps. Or 540 watts. I forget it could be 5 parallel, so 54v, 20 amps = 1kw. That sounds more like it. I believe it was 5 parrallel so thats 1000watts.

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...
Since Air resistance square of velocity and power is the cube, I think that would mean you take 35 x cube root of 1.6 (1800/1000 * 90%) = 41mph.
I am gonna try it out bakaneko cause gasoline is unlimited range and I really need / want and unlimited range ebike. It has to be an ebike cause of registration laws, hence the generator build. Main thing I am curious is whether to go for 72 volts or 96 volts.
 
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this is from high speed ebike videos I see on YT and my own experience on a 72v ebike (44mph top). you might be able to go 35mph on 1kW but that is like super idea conditions and takes time to get there. also, as speed goes up, the power required is to the 2nd power. that curve is super aggressive above 30 mph. sweet spot for ebike is like 22 mph. that is fine, give it a try. just take your time to make it cosmetic. are you going to cut and reweld the frame. you are going to have a battery for this right? i think you will need it for the required peak power during acceleration, which is the fun of ebikes.
 
this is from high speed ebike videos I see on YT and
this is from high speed ebike videos I see on YT and my own experience on a 72v ebike (44mph top). you might be able to go 35mph on 1kW but that is like super idea conditions and takes time to get there. also, as speed goes up, the power required is to the 2nd power. that curve is super aggressive above 30 mph. sweet spot for ebike is like 22 mph. that is fine, give it a try. just take your time to make it cosmetic. are you going to cut and reweld the frame. you are going to have a battery for this right? i think you will need it for the required peak power during acceleration, which is the fun of ebikes.
I dont mind accel too much... Only top speed... I want it to keep up on the road... It needs to be gasoline cause I might wanna start taking my ebikes on 100 mile trips, so it needs to be a hybrid... I plan on having the generator in the front, and inverters are tiny, so maybe in a custom welded front basket thing... Then I will have the DC converters in the triangle frame and speed controller on there too, which will power the wheel. Ill let you know how it turns out...
With the DC converters, I know your 72v ebike has a nominal full charge voltage of 85 volts, yet with the converters I only get 72v or 96 volts... Do you think I should go with the lower 72volts or higher 96 volts? I do wish I could get like a happy medium like 85, but it cant be done cause these are switching supplies at 90%+ efficiency... Not gonna use a boost converter cause lower efficiency...
 
this is from high speed ebike videos I see on YT and my own experience on a 72v ebike (44mph top). you might be able to go 35mph on 1kW but that is like super idea conditions and takes time to get there. also, as speed goes up, the power required is to the 2nd power. that curve is super aggressive above 30 mph. sweet spot for ebike is like 22 mph. that is fine, give it a try. just take your time to make it cosmetic. are you going to cut and reweld the frame. you are going to have a battery for this right? i think you will need it for the required peak power during acceleration, which is the fun of ebikes.
I do recall air resistance is to the 2nd power, and air resistance is force. The integral of force is power, so it would be 3rd power I think which is why i did the cube root. I am a bit fuzzy on some of the physics but idk, practical testing always beats theoretical numbers...!!! GME had a theoretical 2% chance of hitting like 120 bucks today but now its 220 dollars after market!!
 
I do recall air resistance is to the 2nd power, and air resistance is force. The integral of force is power, so it would be 3rd power I think which is why i did the cube root. I am a bit fuzzy on some of the physics but idk, practical testing always beats theoretical numbers...!!! GME had a theoretical 2% chance of hitting like 120 bucks today but now its 220 dollars after market!!

this is the "woulda, shoulda, coulda" situation coming in. I told my friend to get GME at $4 last year. I had AMC calls and sold at $4 (went to high of $20). yeah, I mean the AMC one really pissed me off. white house and SEC now investigating GME; WSB discord server shut down. LUL! today, wasn't that great but my hedges in UVXY did help. I need to hedge more (CC and ratio options to hedge the hedge).

you do know the size of a 1800W generator right? Mine was like 30lbs; yours must be over 50lbs and atleast 1x1.5x3 feet. how are you going to put that in your front basket... also, when i did mine I disassembled the generator to fit it into the frame. that was a mistake as I ffffed up the vibration and noise dampening engineering of the generator. If I were to do it again, I keep the generator intack and just cut and reweld the frame to house it.
 
To go 50 mph for 100 mile trips. Dude. Get a motorcycle already lol. You're going to have more time and $ into a heavy, slow, probably not safe or fun to ride, pig of a s**tcycle that still won't do what you want. You're going to need 4000 watts at least, unless you only plan on driving on an indoor flat track. The real world has hills and wind. Good luck!
 
To go 50 mph for 100 mile trips. Dude. Get a motorcycle already lol. You're going to have more time and $ into a heavy, slow, probably not safe or fun to ride, pig of a s**tcycle that still won't do what you want. You're going to need 4000 watts at least, unless you only plan on driving on an indoor flat track. The real world has hills and wind. Good luck!
there is a 4500w inverter generator on ebay for 400 bucks1!! I am gonna downgrade to 40mph so i can use my 2300 inverter gen.
 
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