[BenHightowerV]

Hi guys,
I'm pretty new to the EV scene. Been kicking the idea around for quite awhile now but life gets in the way, or your young & naive & listen To Someone when they say "It only works for 10 miles then you Gotta charge overnight. Very impractical."
I'm Getting everything together for an electric motorcycle conversion. I see alot of ppl have gone with a 48v motor but it usually tops out at 45mph with a 40 mile top range. The 72v motors can hit 50-70mph but are about a 10-30 mile range.
I realize range is due to the battery, until the better longer lithium comes out.
My question is, if I attach an alternator to the bike, hooked up like a tensioner, wouldn't that work to recharge the batteries therefore making my range limitless?
Any tips, suggestions, even criticism is welcome. I just wanna learn.

 

[frodus]

with a load on the generator, it resists turning, so while it can "recharge" the batteries if being pushed, it'l take more energy to push it than it generates, so it'l actually slow you down.

http://www.diyelectriccar.com/forums/showthread.php?t=13449&highlight=perpetual

You'd be better off with a generator, or spend more on batteries for more range, or just get an ICE motorcycle to begin with.

 

[BenHightowerV]

I already have a '96 Kawasaki Vulcan 750 but I want a ev & I love motorcycles so why not a eBike? I'll look into generators. Thanks

 

[frodus]

What range do you "NEED" and what top speed do you "NEED"..... notice that I didn't say "want", but what are your absolute requirements for both?

A generator is going to need to be at least 5kw to power enough for cruising, at a low speed, and then you'd need power conversion equipment to get from generator to pack voltage.

In the end, the weight, space and cost is better put into batteries.

 

[BenHightowerV]

I need 50mph for up to 60miles round trip. Prob is I don't have access to a wall socket for recharge while I'm inside at work. That's why I was interested in an onboard system To recharge while riding.

 

[frodus]

it's not impossible, but to get that range, you'll need a good sized battery pack, and even if you had a generator, something big enough to run on just gas/generator power would be really large. Maybe something as a range extender would be good, something that only adds to the batteries when needed.

Why can't you charge at work?

 

[BenHightowerV]

I work in a tourist town, river runs behind the building so I park in either a parking garage or along the river on the side of the road.
When you say a big pack do you mean like 6 batteries (72v) for a 48v motor? Is the range extender the same as a generator or alternator? If we were talking I.C.E. I'd know what your talking about but this is all new to me lol.

 

[frodus]

ok, so you can't charge. That means you'll need a large pack of batteries (lots of energy) or a medium sized pack with a decent generator. I haven't seen anyone do a generator on a bike before, so you'll be in uncharted territory.

Next, take the idea of an alternator completely, and lets just forget about it.

When I say generator, I mean a gas powered generator that puts out electricity and uses gasoline. This can be sized such that it's large enough to propel the vehicle with the electricity it generates without using any batteries, or sized such that it generates some power and the batteries supply the rest (range extender).

When I say big pack, I'm not even talking lead acid, so lets forget about that too. You'll need a large pack of at least 6kwh of batteries (volts x amps = energy in Wh). Lead is too large and heavy for you to fit in that bike (750 isn't that huge, but it's big enough to convert). You need something with more energy density per unit volume and one that is high in density per unit weight. LiFePo4 comes to mind. The cost has come down a lot, and you'll replace the pack less. For anything over 30 miles, you can pretty much count on using lithium (for now).

do some more research about batteries and stuff. It's possible, but you better have some flexible budget, because this conversion won't cost less than $5k, and that's bare minimum.

 

[BenHightowerV]

That's basically a hybrid isn't it? Sounds interesting. Kind if exciting considering you said it (possibly) hasn't been done. Thanks for the input, Definitely given me something to think about.

 

[frodus]

yes, it's a hybrid. I am considering putting a 1kw generatoron my luggage rack when I get a chance, to power the charger while I'm driving (if possible), but some chargers don't like the non-sinusoidal waveform coming out of a generator.

The alternator Idea just won't give you anything back, unfortunately.

 

[BenHightowerV]

Thanks for the information. I looked at the LiFePo4 as well, seams for the dame price as 6 optima batteries I could get lighter longer lasting batteries, Which is awesome. If I do end up w/a generator I'll be sure to update/post how I did it.

 

[frodus]

not for the size pack you want, lifepo4 is more expensive. you'd need at least 6kwh, maybe more.

 

[T1 Terry]

Thanks for the information. I looked at the LiFePo4 as well, seams for the dame price as 6 optima batteries I could get lighter longer lasting batteries, Which is awesome. If I do end up w/a generator I'll be sure to update/post how I did it.

Hi Ben,
I'm guessing you mean the LiFeP04 over the optima batteries. Can you leave a small generator running all day if it was attached to your bike? My thoughts were along the lines of a small output unit that could recharge your battery pack while yo were at work.

T1 Terry

 

[nwohater]

I realize you're talking motorcycle not bicycle, but this concept might work for you since you'll have a full workday to let the thing charge.
http://www.youtube.com/watch?v=PJDNWcnYlFo Those generators are small and light enough to sneak onto a 2 wheel motorcycle. You can find chinese versions of those gensets for $100 at harbor freight if you're on a budget, people have reported them to be pretty decent actually. You could start the generator when you get off the bike at work, with a measured amount of gas, and just check it at lunch to make sure it worked and you got all the charge you needed. If it were locked in a vented and fireproof trunk box it might still be there when you get off work.


I'm looking for similar to what you are in my post in this forum, except I'm planning a trike and trailer to haul a big ass generator for unlimited miles, not just 60, and not with a days rest in between use to recharge. lifepo4 batteries are way way more expensive than a cheap generator.

 

[gor]

e-bike hub motor kit on any bike or scooter... combined power or e-range + gas range

few links for OEM hybrid bikes and scooters
http://www.northerntool.com/shop/tools/product_200380038_200380038?cm_ite=233680&cm_pla=Go-Karts, Electric Bikes + Scooters>Hybrid Scooters&cm_cat=Google&cm_ven=Aggregates

http://www.hotrodpocketbikes.com/co...t_id-1999/50cc_600w_hybrid_motor_scooter.html
50CC 600W Hybrid Motor Scooter [Hibrid 50 A]Price: $1,395.00

http://www.popularmechanics.com/cars/motorcycles/reviews/4342510

Orange County Choppers Hybrid Motorcycle Test Drive

 

[scoot440]

Have you considered a removeable battery pack? You could carry or wheel it in for charging and leave the bike in its normal parking place. You can build a much lighter and less expensive bike if your range requirements are cut in half.

 

[elektroboy]

Might be just as simple to make yourself a hybrid.
Take a bike that has a bit too small fuelmotor for your purposes.

You will only have too little power when accelerating and for top speed.
At these moments a small elektromotor can 'help' the main motor.
At the moments there is no need for much power, the elektromotor can work as a generator charching the (small) batterypack.