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Discussion Starter #1
Hey everyone, I just bought a 1980 Garelli Supersport Moped and I was going to use this project as a stepping stone before I go to convert a car. I have a lot of free time over the next month and was hoping to get a jump on this project before school starts again in the fall. (I'm a teacher).

I was hoping someone would point me in the right direction with any calculators that can be adjusted for use with a 49cc equivalent moped instead of a car.

I am looking at motorcycle conversion threads but I haven't seen anything that would have a moped equivalent.

Thanks!
 

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I was hoping someone would point me in the right direction with any calculators that can be adjusted for use with a 49cc equivalent moped instead of a car.
What are you looking for?

In terms of equivalents, it's best to check your local laws as they'll be all over the board.

For example, in my jurisdiction, the laws haven't caught up to account for electric, so, all I tell them is that it has zero ccs of displacement (no pistons, no piston displacement, nonsensical term to apply to electric) and, the conversation ends there. It's approved.

Some jurisdictions will say things like, 49cc is equivalent to 2hp, so, as long as your electric moped is under 1500 watts (2hp) it's okay. Some will specify if it has to have a limiter, or if the label spec is acceptable. A limit would be active an refuse to supply more than 1500 watts. A "1500w motor" might be spec'd for all kinds of things. For example in RC use, 1500w is generally right at the absolute max before you blow the motor up. In industrial applications, it's rated to handle 1500w continuously, 24/7, in the worst possible heat next to a boiler, with all it's cooling surface blocked by dust and grime, for 50 years, with a 300% overbuild on top of that if it's mission critical... and you can easily get 25x that out of it.

Calculations are generally the same for a car top-speed wise, as bikes aren't much more aerodynamic than an entire car. Weight-wise (hill climb/acceleration) bikes are 1/4-1/8th the weight of a car.

http://www.enginuitysystems.com/EVCalculator.htm
 

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Discussion Starter #3
Hey thanks man! I did check a bunch of stuff in my state, Delaware.

I have decided to run a 72v setup, currently deciding on whether or not to use the Goldenmotor. I did start working on the batteries tonight. I'm going to run 2 36v batteries. The pics are showing one of the batteries. I am trying to see if I can make them rugged enough for me to use them.
 

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Kool moped!

How did you get the pic to post?

Wow, 3kW, or 72V
...do you need that much power?

IMO
For your first project/venture into electric vehicles...

Try a simple, 48V 1,000W MY1020 type of a brushed motor
...it's mostly plug-n-play
…& it will scoot you right along
...for A LOT LESS CASH

Like this kit, (~$100.00 delivered)
...it comes with the motor, a matching speed controller & even a twist throttle
https://www.ebay.com/itm/48-Vol-100...R40&rt=nc&_trksid=m570.l1313&LH_TitleDesc=0|0

These little motors are very powerful

The Torsk kart has this size motor
...using (4) 12V 15AH SLA batteries
...goes ~25 MPH
https://www.youtube.com/watch?v=76-QhtSYhM8

Your moped with it's, less over all weight & rolling resistance, should do that easily

Then, (for your next project) go bigger (if necessary)
 

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Discussion Starter #5 (Edited)
Hey Functional Artist.
You have to upload the pictures under the "Additional options" section in the forum post, then click on "Manage Attachments." That will open a new window and then click on "Choose File." That will allow you to select the image and then click on "Upload." Then you can close the window or add more images. It will then be added to your post.

I saw some of those parts on eBay, I decided to go with a little more customization and power because I would like to ride it comparable to its original speed and range. And I am getting my brother to make a custom mounting plate. I can always upgrade the batteries later.

I saw this calculator from the Electric Scooter parts website that is rather helpful. http://electricscooterparts.com/motorwheelgearratio.html

With your suggestion, I might use the goldenmotor 48v- 3kw motor instead of the 72v. I think it's just changing the controller to tell the motor that voltage. I don't know yet because I didn't buy anything.
 

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Golden Motors "look" nice
...but, is it worth ~(6) times more

It's your $$$

IMO
Your not gonna go (6) times faster
...or ride (6) times longer

Kool, they musta fixed something
...cause pics wouldn't load or it kept sayin "file too large"

This is my latest project
...it's a Tri-Quad
 

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Discussion Starter #7
Hey everyone, I am getting the motor and some peripherals on Thursday August 16th. I was wondering what gauge of wire that my batteries would be using if I'm running 2- 36v packs in Series? Is there a guide as to which size wires will go from each battery to the controller? I am getting ready to finish one of the batteries and am looking to charge it soon. The controller says it can draw up to 192 Amps. I don't think I'll program it to do that.

Thanks.
 

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Discussion Starter #8
I got the motor and my bro welded a steel plate to the frame. Then I drilled out the frame so I could bolt it to the frame!





I was wondering. If I step down the 72v to 12 or smaller what would you recommend I get so I could charge a phone or some sort of 5v accessories?

Also does any one know where I can get a 11t sprocket with a 20mm bore and a 5 mm key? I cannot find it anywhere...

Thanks!
 

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I was wondering. If I step down the 72v to 12 or smaller what would you recommend I get so I could charge a phone or some sort of 5v accessories?
I'd step it down to 12 using any normal DC/DC converter since you'll need that anyways, and then add a cigar lighter port or just add on a normal $2 USB car adapter.
 

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Discussion Starter #10
Omg! I got it to turn over today! ... for like 5 seconds. Then I tried again and it doesn’t work... has anyone had any luck with the golden motors?

My set up is 2 - 36v custom made 18650 10.5 ah batteries running in series through the controller. I turn on the switch which turns on the contactor and the controller is on but the throttle produces nothing besides that first time.

I plugged the controller into the computer and it appears to be ok?

Other Updates:
Got the sprockets, although I had to get my brother to grid the drive shaft down since it was the wrong width. It was the right pitch but the key is too wide compared to the shaft that the motor has. Does anyone think this will shear it off?

Also got a back sprocket. 42 teeth. So my ratio is 12t-42t so 3.5:1 gear ratio.

The images aren’t too exciting. I didn’t get any good ones today. But I did get it to turn over!


 

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Discussion Starter #11
Ok, so big update here. I decided to look at the golden motor forum for all my vector controller issues and they helped me! So it runs now!

Does anyone know any generic Graphic User interface displays for displaying all data, speed, voltage, watts etc.?

Also, I tried to make my own seat and my brother is going to help me remake the back end so I can use the 350mm shocks that I bought for the new backend when it's completed. I'm pretty close!

Looking to repaint the wheels in the next week.
 

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Discussion Starter #12
Hey everyone, trying to figure some nitty gitty stuff as the project approaches completion.
So, I think when I was testing my initial build with my contactor I might have had the wires in the wrong order. Now I am putting it together, hopefully for the second to last time, I am concerned about the contactor shorting out the system like last time. How can I separate the positive and negative terminals of the contactor shown below? (The first pic with the orange object) Also, do you think I should buy rubber grommets to separate the contactor from the frame?

I also attached an overall image of the bike. Do you guys recommend trimming the hall sensor cables? How would you attach the cables to the frame?

I don't really have access to anyone who can build a custom cover for all my components, so I cut out the old gas tank and am trying my best to let it fit over the batteries. I want to make all the cables as clean as possible as some of them will be exposed.

I also need to custom build a seat.

Thanks for your help!
 

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Discussion Starter #13
So, I just realized that step-down converter is only rated to 72v. When I am fully charged I'll be running around 80v. Will that blow the converter?

Thanks.
 

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It's coming together nicely.

Yes, I would cover the "open terminals" on the contactor
...all high voltage terminals should be covered.

I used rubber boots (like used on riding lawn mower battery terminals) to cover the contactor terminals on my El Moto.

Going by lead acid specs (which most stuff has been based upon)
A 12V lead acid battery is ~13.3V fully charged
…& 6 x 12V batteries would be ~ 79.8V

So, it looks to be in the right range, to me
 

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It's coming together nicely.

1.) Yes, I would cover the "open terminals" on the contactor
...all high voltage terminals should be covered.

I used rubber boots (like used on riding lawn mower battery terminals) to cover the contactor terminals on my El Moto.





2.) Going by lead acid specs (which most stuff has been based upon)
A 12V lead acid battery is ~13.3V fully charged
…& 6 x 12V batteries would be ~ 79.8V

So, it looks to be in the right range, to me
Yup, I know.
The first part of my reply was just commenting on covering your contactor terminals.


The second part of my reply applied to your 72V to 12V convertor question.
…& to that, my point was that manufacturers factor in "fully charged" battery packs.

So, IMO applying ~80V to a 72V system should be within it's "standard operating parameters" & not hurt anything.
 

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Discussion Starter #18
So, I know this is weird, I was hoping to have 2-36v batteries running in series for 72v for space. The motor draws 94A max continuous. If I have a BMS on each of the batteries, would I need that BMS to have 100a protection or 50a protection? Does each battery pull the amps equally or are they both pulling 100amps?

I was looking at these BMS to see if I could use them, they are rather pricey.
http://www.batterysupports.com/36v-...-lithium-ion-lipolymer-battery-bms-p-390.html

Would it be easier to just build a 72v battery? (20s with 100a protection). I wanted it to be 2-36v 15a in series to build the batteries and have a few of them I could swap in and out?

Does that make sense?
 

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Discussion Starter #19
Ok! The battery is done! However...

I recycled the series connection from my old battery connection wires when I went to a single 72v battery. I didn't realize that the plug posts were switched. I plugged it into my system and then turned on the bike. A small spark and all the fuses blew. I tested my battery, and I replaced the 12v system fuse. I switched the plugs to be correct and now I have no movement from the motor. But the battery and the 12v systems are working now. I assume if I replace the "100 amp- 32v MIDI" fuse, everything will work again?

Image of the fuse. https://imgur.com/gallery/kdMJXm3

Do you think that my controller was saved by the fuse? The 12v system was, (10amp fuse). I feel like if the 12v system was the controller was? What happens when you reverse the polls?

Thanks, everyone!
 

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Often the $50 microcontroller blows up to protect the $0.25 fuse. :p

The fuse is there to prevent wires from overheating and causing a fire, not to protect the electronics. By the time it blows, anything electronic has been dead in 1/1000th that amount of time.

Nothing much else to do, replace the fuse and figure out if it still works.
 
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