Feature

Still Sliding

Upgraded Electric Drift Trike

Jason Greenlow

Issue 40, November 2020

The Trike V2 electric drift bike has had some improvements, giving it more power and better performance.

In Issue 9, March 2018, we introduced you to Jason and his one-of-a-kind electric drift/slider trike. The trike was made using parts from an old go kart and bike. It has a motor from an R/C plane, powered by a battery bank made from second-hand Li-ion batteries from used laptops.

When Jason recently got in touch about his Trike V2, we asked him to tell us more. This is what Jason had to say:

I built my first electrical 3 wheeled slider trike in 2017 which I sent to DIYODE magazine and was fortunate enough to have my trike published.

I have had multiple people, friends and family ask me if I could build them one, which I’m happy to do once they show that they have the money because $1000 including all the parts and 6 hours labour is a lot of time and money.

My first trike was a single wheel driven trike which I found to have setbacks. For example, the trike would slide better in one direction than the other, and the power from the brushless motor would make the trike loose traction from a stationary position. Some would say that is a good thing. The trouble was if you want to get up to a good speed, limiting the throttle power to prevent wheel spin was the only way.

The brushless motor on Trike V1 is an R/C 70kv aeroplane motor. At the time of the first build, I believed the motor would not handle a solid rear axle with two spinning wheels and my body weight so leaving one wheel to do the driving was best. As a bonus, the turning circle while pedalling made turning easier.

I built V2 because a good friend paid me for the trike in full before any existence of V2 had started and honestly, I couldn’t wait to start. I said the build may take up to 8 months because it will have to be built in spare time and on weekends when my loving wife can’t find me.

For this new build, a solid rear axle was key for me and to prove to myself that I could build a functional trike with good speed and sliding ability in both directions. First, finding a bearing size that would fit nicely over a steel pipe, using a go-kart axle is expensive. Using two 35mm pillow block bearings and a 33mm pipe, I welded two beads down the pipe where the bearings would sit and ground the beads until the bearings would fit comfortably in place and 1m apart. Then machined a set of go-kart hubs out from 28 to 33.5mm to slide onto the axle next to the pillow blocks.

Full handle grip lever.
Frame uses 19mm x 1.4 square pipe.

After building a strong box frame to hold the axle assembly, a chain and two sprockets were installed with a heavy 180w brushless motor and a 150-amp electronic speed controller to get this mean machine moving. Using Pedals on the front wheels creates possibilities for cool stunts and if your battery goes flat, pedalling can get you home. The handlebars might look longer than normal BMX bars, that’s because they come from a Motocross bike and was used to match the size of the rear axle, BMX bars looked too small.

Previously on V1, I used a 200amp ESC (Electronic Speed Control) from an R/C boat which had plenty of push to drive the 70kv motor, however, the downside to this was the fact that the ESC and motor are sensorless which means the ESC cannot see what phase is next and never knows what phase to start the brushless motor on. This meant that every time the throttle was pressed, the motor would groan a little until the correct phase lined up and the motor was able to spin. A sensor type ESC and brushless is the best for this trike. From stationary, there is no delay with acceleration, the second you want to light up those wheels the ECS is ready for action.

Solid rear axle.
180W brushless motor.
Chain and sprocket.

If the kids want a turn I have installed a 3 speed switch to gain a slow, medium and fast function. The ECS has slow, medium, fast programmed into it, limiting the current to the motor so all you need to do is add a switch.

On V2, I have bought all my electrical parts online, so everything is new and designed to almost plug and play. Buying the right parts for the job would mean fewer setbacks in the end. Minimal soldering is needed if anyone wanted to build their own. A few online videos should be enough to learn how to solder and have your trike wired up in about 20 minutes. The speed controller has the wires named and coloured so it’s easy to understand what wire goes where.

Power key switch and 3-speed toggle switch.

My advice is to look for the electronic speed controller first then you will know what size battery the ESC needs and what size motor the speed controller can handle. For the throttle, a thumb lever or a handle grip lever are the options. I used a thumb lever on V1 and V2 has the full handle grip lever. To me, it feels more natural and you have better control.

Li-ion E-bike batteries are the best way to go these days in my opinion as building your own battery pack and getting a good BMS (Battery Monitor System) is highly time consuming. If you have used old cells from laptop batteries as I did in V1, getting a bad cell is the last you want to be finding. It comes down to looking for that needle without disturbing the haystack, so building another battery pack becomes your best option.

E-bike battery packs come with a battery charger, BMS and are neatly placed in a solid case. Even though the cost is high to buy an E-bike battery pack, it becomes less of a headache in the end.

The rear axle and bearings, wheels, brushless motor, ESC, chain and sprockets all needed a new frame design, which needed to be robust and light enough but still looks cool.

I had to think of what type and size pipe to use. The front of the trike frame could stay the same because there was not a lot of change, mostly the back of the trike.

I used 19mm x 1.4 square pipe and built a square frame where the axle could spin in the centre of so nothing could get tangled around it like feet, thongs (jandals for NZ) and hands. To keep the throttle wiring from being snagged while riding, I ran the wire through the centre of the frame where it meets the ESC on the back.

Not everyone has access to a welder or has never used a welder. Not to worry because drilling holes and bolting the frame together can be just as strong. If you research how to bolt a strong frame online, you should be able to find something to suit in a short time.

Motocross bike handlebars.
150-amp electronic speed controller.

I spent a lot of time online finding out how to build a strong frame, especially for this build due to the fact that the Trike was sold before I had started.

If you’re like me, thinking of your next build is just around the corner, big or small. Some of my projects are only pocket size with a 3D printed case which I hope to show off in another DIYODE Mag Issue.

If you would like more information on how to build your own trike, you can PM me on Instagram @geek_greenlow where you can also see some of the other crazy gadgets that I have made.

Jason Greenlow

Jason Greenlow

Vibration Analyst and lifelong maker. Living in Perth, from Christchurch, NZ