Electric Tricycle - Build from scratch

[probey]

Hi guys, david wood here from Brisbane Australia.

Im looking to build my own electric tricycle, and i've had a few ideas as to what i want - but i would like some suggestions and support before i start.

My first thought was getting one of those greenmachine trikes, tearing the frame down and building it back up from there - However, the tube steel is only very thin from memory, and im not sure it will support the weight i will have on the vehicle.

My second thought was to buy two identical mountain bike frames, tear them down, cut and weld as necessary and build up from there - Again, unsure of the stability of the frames.

My third thought however, was to build a basic trike frame from 25mm RHS Steel, use some bike parts (steering colum, front shocks, brake lever's and disc breaks, and maybe the gear system from the mountainbike as well).



My goal for this project is to make a reasonably powerful electric tricycle (500w - 1000w), with a top speed of around 30KM/H, and a range of about 5Km's before it needs charging.



I know a fair bit about electronics and electricity, so my questions aren't really about that as such - but more so about the actual design of the electrical system (which motor, voltage, gearing system, etc)

From this diagram i've come across, i know i wont need much in the way of electronic components.

Here's the current parts list i have in mind for the moment.

24v 1000w Permanent magnet DC motor
24v 20amp Electronic Speed Controller
Electric handle throttle for speed control
2 x 12v 20Ah LiPo batteries (the ones used in RC hobby stuff) - Wired in series for the motor

The on/off switch will be a 12v key ignition i have lying around, and the batteries i will charge from my 24v solar charge controller.

Has anybody got any thought on any of this?
Or if you've done something similar, i would love to see your work and understand how you did it.

Thanks!!

 

[Wheazel]

I suggest you check around different buildthreads for electrical setups. The picture you posted makes me think you could get some inspiration from other builds.
Depending on what you are going to use the bike for, there are drivealternatives that are favoured for different circumstances.

I would also shoot for a much higher useable range than 5km unless this is some very special purpose project.

 

[Dui ni shuo de dui]

Hi guys, david wood here from Brisbane Australia.


Thanks!!

Hello probey,

Here in china, we have electric tricycles everywhere, so this is not really original

They are usually built following the picture you drew, so the basics are the same. It's just that with 24V of batteries and a 20Amp controller the performance may be miserable.

Actually, I think you should define first what will be the use for this stuff. Carry heavy loads? people? How far of a distance? on flat ground?
Answering those questions will help you decide better what kind of structure you may need to build, so, as a consequence, what will be the total weight to move and the power needed to do that.

Usually here tricycles runs at 48V minimum, with 500-1000W controllers. If it was, me, I would probably not go under 60V and 3000W controller, just to be sure it'll be ok in all situations.

Here is an example of how they look like:
https://item.taobao.com/item.htm?spm=a230r.1.14.39.2UaV59&id=521164915431&ns=1&abbucket=20#detail

Good build

 

[Dui ni shuo de dui]

Oh, and also, just a remark: usually the battery charging port is directly connected to the battery, not the controller.

 

[SlowCo]

Search around this site:

https://endless-sphere.com/forums/viewtopic.php?f=3&t=44334

https://endless-sphere.com/forums/viewtopic.php?f=28&t=73957

https://endless-sphere.com/forums/viewtopic.php?f=28&t=69419

 

[dogman dan]

I have no idea what you need to carry that a typical adult trike frame can't handle, particularly the industrial model trikes like the worksman.

But if you want to take stuff from a bike junkyard, and make it into a nice trike for the fun of it, I can only say I highly approve.

Here's a fun build I helped Amberwolf get started. I actually made going to his house to build a trike my vacation that year.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833

Some of what we did was in the happy accident category, but starting the frame with square tube imitating the recumbent bike was the best idea of all. That first step made many things easy later on in the assembly.

On line, you can find the rear axle assembly for trikes, if you don't have a trike to cannibalize. I like the way AW's trike turned out, with the rear forks making using rear hub motors possible. So I keep looking at making something similar from scratch, using old BMX frames to construct a trike rear end.

 

[Simonvtr]

Hi David

When I started my Warrior trike build I ran into the same questions.
Get a used bicycle and strip it down to make a trike or buy the bare steel to do it?
After looking around my area for 2nd hand bicycle ranging from 30$-100$ and needing 2 for the headtubes, then checking the local metal warehouse I was surprised to find the cost difference.
I bought 1.5x1.5 inch @ 16 gauge mild steel square tubing for $1.09 a foot.
If you are heavier you can go with a thicker steel 14 gauge, or go bigger like 2"x1.5" and still able to keep the 16 gauge steel.
Square tubing are alot easier to cut angles and weld in my opinion being a noob at it.
Also I did not have to deal with stripping all the paint from used bicycle. I also was able to purchase the headtubes from the same place.

I started out with a dc motor but burned it up after only a couple of rides carrying a bicycle trailer with my daughter in it.
Since then I have switched over to a hub motor and haven't had any issues.

Trike w/mxus 6t @90v HK lipo /30mph
https://endless-sphere.com/forums/viewtopic.php?f=2&t=73065

 

[Drunkskunk]

Sounds fun. How much weight are you looking to carry?
Building a trike because you just want to sounds like a good plan, but worksman trikes can take a thousand pounds or more.

On your electrical ideas, 24v might be ok depending on your motor, but generally it's better to use higher voltage. If you double the voltage you can cut the amperage in half. that will allow you to use thinner wire without melting, be easier on the controller, and also be easier on the battery.

DC motors are the way to go, but you didn't specify what type. BLDC has a significant advantage over brushed motors, and there are a wide verity of ebike conversion kits available using BLDC motors.