Onboard generator

[TWB503]

Before you say “just buy a bigger battery”, well that’s no fun, is it?
I want to put a generator system on my eBike (will this actually happen? Probably not, but I still wanna get some opinions on it).
The two options I have are this:
1) Buy a Honda GX35 engine, it only weighs 7.6 lbs, and then find a way to generate power from the rotational output (probably have to generate a high amperage 12V power and then use a boost converter to take it to the 42V I need). It has a 1 kW mechanical output, which if we have (I’m guessing) 50% mechanical efficiency from shaft to charge, gives us about 500 watts, which is more than what I need (I probably could get by with 250W, so I could run the generator at half throttle?)
Additional info-
.63 litre fuel tank
1.0 kW @ 7,000 rpm
1.6 Nm @ 5,500 rpm
0.71l/hr at full throttle

Advantages-
- Lighter
Disadvantages-
- Will require a lot of work (but that’s fun... right?)
- Probably louder
- I have no idea where to find a generator
- May have trouble fitting to bike

2) I own THIS

So what if I put it on one of THESE!

In theory, this would work, since it weighs 46 lbs, and a lot of these bike racks claim to be able to hold up to 60 lbs.
This thing is as quiet as “52 dBA” and can last “up to 12 hours” on a 1.2gal tank.
Advantages-
-Quieter
-More efficiency from fuel to battery
-Can always upgrade the charger if needed
-USB ports (my bike HAD a USB port, but now it doesn’t...)
-Cheaper (in my case, but only because I already own the generator)
Disadvantages
-Substantially heavier
-Messes up weight distribution
-Might break the mount if I’m not careful

So if you were to build a generator for your eBike, which one would you do?

 

[JRA]

Consider a trailer of some sort.

 

[TWB503]

Consider a trailer of some sort.

I have thought about it, and while this would probably be more stable for the generator, it risks messing up the handling. I need to find a place where I can like try out a trailer to see how it makes my bike feel.

 

[indianajo]

My cargo bike will carry that kind of weight without being unbalanced, but carrying that amount of weight limits the rest of the items you need for long distance touring. Plus it is a lot of money to have in the bag when you duck into a restaurant for a meal. Means you have to tour in a group, and somebody has to stay outside with the valuables. See this thread: https://electricbikereview.com/foru...ng-to-solve-charging-on-the-road.31265/unread
There ought to be some sort of solid state device to convert heat energy of a flame directly to electron flow. Thermocouples are inefficient. Solar cells are getting there but aren't tuned for infrared.

 

[retiredNH]

Too funny. Reminds me of the guy who had a first generation electric car, long before the prius etc. He rigged up a generator in a trailer that he hauled behind to avoid range anxiety. Here's one from 2010:

Range-Extending Trailer Charges Your EV, Carries Your Gear

Of all the solutions we’ve seen to extend the range of EVs, this might be the most unique. A company in Wakarusa, Indiana, has designed a self-propelled trailer that contains an electric generator and batteries that keep an EV charged. Electric Motors and Vehicles (EMAV) founder and president...

www.wired.com

 

[TWB503]

Too funny. Reminds me of the guy who had a first generation electric car, long before the prius etc. He rigged up a generator in a trailer that he hauled behind to avoid range anxiety. Here's one from 2010:

Range-Extending Trailer Charges Your EV, Carries Your Gear

Of all the solutions we’ve seen to extend the range of EVs, this might be the most unique. A company in Wakarusa, Indiana, has designed a self-propelled trailer that contains an electric generator and batteries that keep an EV charged. Electric Motors and Vehicles (EMAV) founder and president...

www.wired.com

BMW did that, but they did that inside the car (i3, anyone?)

 

[Lightning 123]

I believe that would be considered a motorized vehicle.

 

[rich c]

Check youtube. There is a great video on there. You can also use the search button here. It's been discussed before.

 

[PedalUma]

There is a more sensical way.

 

[Dallant]

Too funny. Reminds me of the guy who had a first generation electric car, long before the prius etc. He rigged up a generator in a trailer that he hauled behind to avoid range anxiety. Here's one from 2010:

Range-Extending Trailer Charges Your EV, Carries Your Gear

Of all the solutions we’ve seen to extend the range of EVs, this might be the most unique. A company in Wakarusa, Indiana, has designed a self-propelled trailer that contains an electric generator and batteries that keep an EV charged. Electric Motors and Vehicles (EMAV) founder and president...

www.wired.com

God I hope we‘ve come a LOT further in 11 years!

 

[TWB503]

Check youtube. There is a great video on there. You can also use the search button here. It's been discussed before.

I’ve seen the video with the guy with the orange generator on the back of his bike (that’s where I got the idea for #2 from)
I’m just here to gather thoughts on which one of the two generator methods would be better

 

[TWB503]

I believe that would be considered a motorized vehicle.

Personally, I don’t think putting an engine that doesn’t directly power the wheels would do that (though it might get me stopped, to which I’ll have to explain this!)
The power to the battery could be coming from a nuclear generator on board for all anyone cares, but at the end of the day it’s an electric motor powering it.

 

[indianajo]

As bad as the wind it these days, I wonder if a turbine/generator would be useful for bike touring without staying in KOA stinkgrounds (for the AC plug). Would weigh a lot less than a gas generator, have a lot less drag in the bag than a solar panel, and not emit CO2. After all, almost nobody pedals 15 hours a day on tour.

 

[Bitmugger]

I have thought about it, and while this would probably be more stable for the generator, it risks messing up the handling. I need to find a place where I can like try out a trailer to see how it makes my bike feel.

If you already own a 46lb generator. I'd suggest get a rack and try it mounted there first. See how heavy it is, how unbalanced the bike is. If your kickstand is an issue and the bike won't stay upright with the generator on it, consider a centre mounted kickstand (the ones with 2 legs). It is awesome on my bike when I have a load on the rack.

 

[TWB503]

As bad as the wind it these days, I wonder if a turbine/generator would be useful for bike touring without staying in KOA stinkgrounds (for the AC plug). Would weigh a lot less than a gas generator, have a lot less drag in the bag than a solar panel, and not emit CO2. After all, almost nobody pedals 15 hours a day on tour.

That's a good idea, but the real world is I'd need a really big turbine to generate enough power to have it be worth it. It may add an extra mile or two, but for the price it'll cost, that's not worth it

 

[TWB503]

If you already own a 46lb generator. I'd suggest get a rack and try it mounted there first. See how heavy it is, how unbalanced the bike is. If you kickstand is an issue and the bike won't stay upright with the generator on it, consider a centre mounted kickstand (the ones with 2 legs). It is awesome on my bike when I have a load on the rack.

That's a really good idea, I'll have to look around and try mine out!

 

[retiredNH]

Just stick a gas motor on the bike. Why futz around with electric drive? It adds a lot of inefficiency and weight. Kits are cheap through Amazon, but no guarantees of quality.

 

[BarnBoy]

There is a more sensical way.
View attachment 85464

@PedalUma - when you posted this, I had to laugh as I swear it was a joke. Guess not...
-BB

 

[BarnBoy]

Oops, forgot! @TWB503 please be careful out there! Not only electrical shock but these portable generators are meant to operate on flat level ground. Not a bumpy, leaning bike rides. That much weight up high is not fun to ride. Old bike-packing trips tell me this. Read the manual on the generator to make sure OK to shake rattle and roll...
-BB

 

[Bitmugger]

Just stick a gas motor on the bike. Why futz around with electric drive? It adds a lot of inefficiency and weight. Kits are cheap through Amazon, but no guarantees of quality.

My son has a gas bike. Fun to drive but a 100% different experience to pedal assisted biking. The gas bike is a sit back and watch the view type ride. Not for me, I like to pedal.