Nissan Versa Forums banner

1 - 12 of 12 Posts

·
Super Moderator
Joined
·
1,105 Posts
Discussion Starter #1
So, Ive wanted an electric motor for some time and thought about making an ev or something. Well, browsing walmart found one for 170 bucks. I see bicycles are about 100 bucks depending on options. Now 48 volts worth of power is another issue.

Its rated at 20 amps, so that in a lithium battery with case and bms is like 10 lbs 500 bucks. Doing that with lead acid of agm is upwards to 100 lbs and 100 bucks.

So, looks like I can either trailer the battery or gothe lithium route? One idea I had was to use this as a motor for a pit bike. I would use the inner hub to spin a timing cog like belt and get a matching cog for the drive wheel. I know it would go maybe 10-15 mph, but thats all I would need around the home. I currently use the riding mower for checking the mail if its not that when I come home of a day.

Man, who knew the batteries would be the hold up?

Plan B? Anyone got 170 bucks and near Richmond, VA want to take it off my hand?

To add insult to injury I have 2 industrial lithium batteries. 24 volts each 80 amps and about 50 lbs each. :|
 

·
Registered
Joined
·
216 Posts
Aw man that is right up my alley! Build it!! Build an ebike!

I slapped one together in my college dorm room years ago and it was the funnest thing ever. I bought the motor/hub used, got a free junk bike frame and went nuts.
Lead acid isn't the worst way to go, mine was setup at 36 volts and it was heavy, probably a 60 pound bike, but still quick I could go 17 MPH on it no problem and hold 15 MPH up hills.

Picture time!









I miss that old bike, it was really handy I rode it all over campus and in town. A little small but that used motor/hub I bought had a fixed rim so no option to add a larger tire to get it on a bigger bike frame, I wish I would have had a 26 inch tire!

You said you found the motor at walmart? In store or online? I assume yours is a brushless motor also? Did it come with a controller? Did it come with a freewheel hub and gears?

I do have two spare brushless motor controllers lying around if you decide to pursue the project, although you can find them cheap anywhere nowadays. You also need a throttle/pot.

One option you could explore would be to build a battery backpack. A little clunky perhaps but then you can save a lot of effort on figuring out how to mount batteries on your bike, and upgrade to lithium someday. The pictures above are of my second electric bike, my first one the batteries where in a backpack with a quick connect power cord.

I used 12 ah batteries in the project shown above, I could go between 7 and 14 miles depending on how I drove it. If you don't need to go far 10ah batteries may suffice which saves some weight and sometimes you can scavenge those cheap as they show up in used computer battery backup systems and stuff.

Now you got me all excited about ebikes, I wish I had more time and money!

This is an old Suzuki motorcycle frame I hope to put a large brushless motor in someday:
 

·
Super Moderator
Joined
·
1,105 Posts
Discussion Starter #3
Nice setup. Thanks for the encouragement. I am just wanting to do it right the first time and never really notice how expensive a built lithium pack is. The motor says it needs 48 volts 20 amps. In lead thats heavy with a bike. I am thinking about a trike, but Id like to be able to transport it.

I need to condition my 48 volt industrial pack then Ill see how powerful the motor is. I may rig something up and try it in my backyard. If it goes well Ill see about the bike.

Im mixed on the bike. As a kid we had a range of them from 20 inch to 27 inch and single speed to 21 speed. I think we liked the 20 inch one best as you were lower to the ground and the single speed let you get up to speed quickly and didnt get winded maintain it.

Then Ill try my luck at lacing a rim and worse to worse take it to a bike show. Mines is a front hub/wheel motor.
 

·
Registered
Joined
·
216 Posts
It will be a fun project to play with no matter what. Even though I only ran mine at 36v I had terrific torque with that tiny 16 inch rim. Had to make a poor man's torque arm to keep the wheel from busting loose (which it did once or twice anyways) xD

 

·
Super Moderator
Joined
·
1,105 Posts
Discussion Starter #5
Ha, ha, ha. Adjustable wrench and hose clamp. :nerd:

Went to batteries plus for ideas. They said Id need 100 lbs of batteries and it wasnt practical. He googled some lithium 48 volt packs and said to just buy one online.
 

·
Super Moderator
Joined
·
1,105 Posts
Discussion Starter #6
I just purchased a second kit. >:D 2000 watts, I believe 760 watts is like 1 hp. :surprise

Im mixed on making a kick ass 3 wheel tri/scooter, pit bike or a wheelchair. For the wheelchair route Ill get a set of push rims to mount to the wheel rims. It would look like or even be a regular metal chair and under would be the batteries and I would wear the throttles in my hands like gloves.

For the pit bike Id snake a cog/timing belt like around the 2 hubs to the rear wheel. If I can get small enough rims I might use these as the wheels and have them on the front and rear. :surprise
 

·
Registered
Joined
·
216 Posts
Cobb said:
They said Id need 100 lbs of batteries
What? No, four 12v 14ah batteries would scoot you around long enough to get bored before they were dead, and that would be 36 pounds. What did you tell them that you want 20 mile range? Because then they would probably tell you yeah you would need a lot of SLA.

You might be over-estimating how much power you need, if you look at other people's 48v 1000 watt bike projects on youtube you see they are reaching speeds close to 55 MPH on that setup. I had 36v 720 Watt setup weighing over 200 pounds with me on it and I could scoot around just fine (small tire tho).

I'm just saying you might not need to worry about how to use both motors together, if they are brushless it would be pretty hard to sync them each would need a separate controller, and 2000 watts is plenty to haul you around. 760ish watts is roughly equal to one mechanical horsepower but the comparison is not apples and oranges, those electric motors will give you nearly 100% torque from 0 RPM to max unlike a gas engine.

Just my 2 cents I think after you slap one thing together and ride it around the yard a couple times it will all make sense and it will be hella fun. I have an old tricycle laying around and kept it thinking same as you maybe I'd find a way to hook up my hub motor to drive it and ride it around a little. I think my tires have rotted off of it as this point tho...
 

·
Super Moderator
Joined
·
1,105 Posts
Discussion Starter #8
Re-read the instructions and it recommends 17 amp hours battery capacity. I was going to use 4 u1 d eep cycle batteries 37 amp hours. 70 bucks each. The kit came with a lead acid battery charger, so I got a charger if I go with lead and make a lead sled.

Thinking about a pit bike setup.



Id buy the kit pictured above, then as you can see from the frame below put the bats where the engine would go. Id get a bike shop to lace up some wide 10 inch rims or so 3 inch wide tires. Both wheels would be the hub motors I purchased. Id use a linkage for the throttles.



Then all I need is brakes. >:D
 

·
Registered
Joined
·
216 Posts
Cobb said:
Then all I need is brakes.
Do your controllers have regen braking capability? Mine did, and it nearly threw me over the bars when I used it! You never really gain that much energy back on a bike that way but it does make a decent brake.

I'm still skeptical of the two motor setup, two concerns:
1) the motors are mis-matched. People do dual drive hub motered bikes not unheard of but usually with two motors of equal power and specs. I guess as long as both of yours have the same final RPM rating you might get away with it but something to watch out for.
2) Your battery requirement increases because now you need a battery that can supply for a total of 3000 watts, and thats a lot of juice!

Not saying don't do it, but I still don't think you will ultimately need more than the 2000 watt motor to have a fun quick bike and you can save a lot of weight and complexity with doing a single motor setup. Need vs want tho...

Here is a thought, coming from someone who loves to over-complicate things before he even gets started, what about starting out building it with just the one 2000 watt motor in the back and then if you decide to later you can swap in the front motor as well?

Just my two cents, do it however you like and have fun doing it :thumb2:
 

·
Registered
Joined
·
216 Posts
Ohhhhh I get it, when you said

Cobb said:
I just purchased a second kit. 2000 watts
I thought you meant your second kit was a 2000 watt unit, but you meant two 1k motors together = 2k watts. I'm on the right page now.

Yeah double 1k setups are fairly common, great traction benefits xD

You were saying before you were not sure whether to do a pit bike or a tricycle or a wheelchair... think I found an idea that has the best of all of them... :grin

 
1 - 12 of 12 Posts
Top