Cortes Island Inventor Completes Cargo E-Trike

[Cortes Island E-Bikes series]

For a little more than two years, Cortes Islander Gabriel Dinim worked patiently and steadily on the design and construction of an original, custom electric cargo bike with three wheels. By early summer of 2020, his project was ready for its first test-drive… and has since been frequently sighted on Cortes roads.

Gabriel says this bike effectively replaces his truck, and he uses it daily for travel and cargo hauling. Equipped with regen braking, turn signals, mirrors, brake lights, disc brakes and a substantial drive/motor system, Gabriel’s bike is a serious EV. It enables him to travel to Campbell River and back on a single charge, as well as all around Cortes Island.

As part of the Currents E-Bikes on Cortes Island series, I interviewed Gabriel about his project.

Gabriel Dinim's cargo e-trike

Why Roll Your Own?

CC: There are so many e-bikes on the market these days, some of them with good cargo capacity. What inspired you to build your own custom bike?

GD: No one was offering the features I wanted. I had very specific requirements. I wanted cargo capacity and manoeuvrability, especially good handling on steep hills. And I needed to fit on the ferry as a bike, so I didn’t want to be too wide or long.

CC: So a bike pulling a trailer was too long and handles strangely — I’ve pulled heavy loads on trailers, so I know what you mean.

GD: Yes and those Euro-bikes with big front boxes, those have been around ever since I was a kid in France; they are great bikes, but to me they are really for city streets, you know, flat and on pavement. But here there are hills and gravel.

CC: So you needed something that was manageable on steep hills and gravel roads, but could carry a serious load.

GD: Yes because I have homesteaded pretty much 40 years and I make most of the stuff I use. So I need to carry 2×4 lumber 8 feet long, for example.

CC: So you needed to put the cargo beside you, not behind or in front like most cargo bike designs.

GD: Yes I needed drivability and capacity, both. And no one is offering this, I could not find any commercial bike that met my requirements. So I had to design my own bike.

Another view of the cargo e-trike

Three Wheels Good?

CC: When did you settle on three wheels as part of your design?

GD: I knew from the start I would need three wheels. Today my sense of balance is OK, but I’m getting older and someday I may have balance issues. Also with three wheels I don’t need a kickstand or to lean the bike up, I just get off and it sits there by itself.

CC: Your wheel placement is quite clearly motorcycle-and-sidecar, not bike plus trailer, or even trike. Trikes are usually two-rear, one-front (or sometimes the reverse). Why did you go for the motorbike and sidecar layout?

GD: Well that was lumber again, with the load next to me it can be quite long and I can still steer. I started out pretty open-minded about wheel placement. But the conventional trike I dismissed right away, as you can’t carry long cargo. I wanted to fit easily on the ferry, as well as have good handling even with a long load.

CC: So how did you refine the placement of that third wheel — the mechanical factors are pretty complex.

GD: I spent eight months on the internet researching other people’s projects with three wheels. No existing one was quite what I wanted. People were starting with a stock bike and clamping or welding on a frame. So there was nothing I could just copy. But I know I can learn! So I studied motorcycle sidecar design for months also, the wheel placement, trying to find out the range of possibilities. I knew I didn’t want to use a stock bike frame; I’m getting older and don’t feel like swinging my leg high over the saddle.

CC: But a conventional step-through or mixte frame doesn’t offer much purchase for attaching a sidecar structure…

GD: Exactly, so I decided to make my own frame from scratch and then the bike is all one piece, I did not want anything bolted together.

Gabriel Dinim's cargo e-trike (3)

Engineering Decisions

CC: After that, I guess box beam aluminium was an easy decision… the weight-to-strength ratio, workability, and so on.

GD: Yes, aluminium is as easy to work as wood, and I have some experience with metals because I used to design industrial tents. Practical experience anyway, I was not an engineer but I did learn that aluminium is great stuff. So I decided on box beam, all one size for the main frame, half size for the uprights and details. And I could get that from Campell River, from Metal Fabricators. Lane 8 would bring it over for me. So that made it easy.

CC: Fork angle was probably a bit of a decision?

GD: Not really because, you know, there’s an optimum position for the height of the rider, seat, bars, and fork angle. And conventional bikes and motorcycles pretty much have established that. If you rake the fork out too far you get handling issues, also if it’s too steep and close. So there is really only a limited range in practise. I knew my height and seat position and arm length, and that determined the fork geometry.

Front forc and disc brake of the cargo e-trike
Front fork and disc brake

CC: Disc brakes were a no-brainer given the carcass weight and cargo…

GD: Of course, disc brakes were the only option. And then I had to figure out the braking. I ganged together the front wheel and sidecar on the front brake lever, and then the rear wheel has its own brake lever. But in practise I mostly use them all at once. So I have disc brakes plus the regen, and even with a heavy load I have enough braking power.

Lithium-Ion cells assembled into a battery unit

Battery and Charger

CC: How did you spec the battery pack, range, and so on?

GD: I didn’t know enough when I bought the batteries! I did some calculations but they were mostly guesswork. But fortunately I built a battery that can be reconfigured. I got the lithium-ion cells from Hong Kong, and an interconnect system by Vruzend from India. So I didn’t have to solder or weld the cells together, and I can change the overall battery dimensions and even add more cells to raise the pack voltage. So I started out with 36 volts and then upgraded to 48. I am getting the range I hoped for.

Lithium-Ion cells from the factory

CC: And what range is that, with normal driving?

GD: 80 kilometres average, but on the island more like 60. On the flat in perfect conditions I would say more like 90-100, but that never happens. In practice I would never run the battery down that far. I generally charge up after every trip.

CC: How much do you have to pedal?

GD: I don’t. I designed it so I would not have to pedal, except perhaps to get home in an emergency if the drive system failed. So those distances are without me helping the battery at all. I have a bike computer that shows me my battery performance and state of charge in realtime; it’s called the Cycle Analyst and I love it. I can see the regen feeding a bit of power back into the battery, for example.

CC: And the charging time?

GD: It uses just a 120v charger so it takes a little time. If it was really flat it would take 12-14 hours, but I never let it get that low, it’s bad for the battery. Mostly I would say four hours to top it up after a day or two of use. I usually only charge it to 80 percent because that is kinder to the battery, but tomorrow I have a long trip to Campbell River so I will be charging it overnight all the way to 100 percent.

CC: Have you noticed a difference in your Hydro bill?

GD: No, I can’t say I have. It is so few pennies to charge the bike up. I think it is about 26 cents maximum to charge it, from the lowest that I would ever draw it down. So maybe eight or ten cents for my normal charge.

Typical MXUS high power hub motor for E-bikes

Hub Motors

CC: I notice you went with hub motors rather than any kind of chain drive.

GD: Yes I knew I wanted two wheel drive. Essentially I needed one motor just to move the weight of the bike and battery pack. Because it is quite heavy, the battery alone weighs 50 pounds. And then another motor to move the rider. So I knew there would be two. I put them on the front and rear wheels, so the sidecar wheel is passive; driving that third wheel is just too challenging.

CC: Right, because any speed mismatch between front and rear just results in a bit of stress or freewheeling, but speed mismatch on the third wheel would affect steering…

GD: Exactly. And I was inspired by recumbent E-bike design, where instead of long chains you see hub motors. I found my original 36v system was just not adequate for the island with our steep hills. Well maybe it would be OK if you pedalled a lot but I don’t want to pedal a lot! So that’s when I upgraded to 48v, more powerful motors.

Where to Get the Parts

CC: Where were you getting all the parts for this?

GD: Well to begin with I sold my truck to get the capital for this project, so I had funds.

CC: So that was the moment of commitment!

GD: Oh yes I was quite committed. And I found a wonderful supplier in Vancouver called Grin Technologies. I think they have at least one or two geniuses on their staff. They are maybe the most advanced e-bike techonology on the West Coast. They import parts — very selective about quality — and also design their own. They use use MXUS [Chinese company] to fabricate their own custom motors. And they have all the matching components, wiring harnesses, controllers.

CC: So it’s like a high-end kit you can get from them, you can be confident the components will play well together?

GD: Yes, and there are lots of builders, I am just one of hundreds. But very few build their own frames! So they were interested in my project, and I had very good service. I recommend them, absolutely. I learned the hard way that these motors have terrific torque and you cannot just slam the throttle on a hill; I broke the torque arm that came with one of my motors, and the motor spun and sheared off its wires. That would be very hard to fix. And they replaced it for me, no problem. So then I designed my own much stronger torque arm!

CC: And does Grin offer the other bike parts, like brake levers and grips and so on? Or did you go to conventional bike stores for those?

GD: I bought from different bike stores, many parts. Mostly Chain Reaction which is a big company, but I also ordered parts from Holland and other countries. I needed also to get specific tyres, because the tyre footprint has to match the horsepower, and then I needed tyres that would work on gravel. So that was another research project.

Front fork with cardboard prototype bracket

CC: So how did you design and model your frame, did you use CAD?

GD: No, I did not use any CAD program! The first thing I did was build a 4×8 table. I did draw parts on paper, but mostly I kept the design in my head; I’m pretty good at doing that. And I made cardboard and wooden prototypes at times. But mostly I laid stuff out on my table, fitting the parts together, getting that core geometry right. Actually it all starts with the sidecar, and making the battery pack fit into the sidecar floor. That was the starting point.

Layout on the work table

CC: You said you are good at learning, but I notice you didn’t learn to be a welder to put the frame together. You hired a pro.

GD: Yes I hired Izabelle Perry here on the island who is a very good welder, and it was a lot of fun to see her putting it together. I had cut all the pieces precisely, then I assembled it with screws and Gorilla tape — so all she had to do was weld it together. It was fun to watch! I enjoyed working with her.

Izabelle Perry welding up the frame

How Long Did It Take, and How Much Did It Cost?

CC: So how long did the whole project take, start to finish?

GD: It took me I would say two years. Of course I did not work eight hours a day, more like four.

CC: How much of that was the frame and design — I mean how long did actual assembly and test take?

GD: Oh I think it was only three months from when the frame was finished, that I first tested the whole bike.

Very first test drive!

CC: And if it’s not too intrusive, can I ask how much it cost in the end?

GD: Oh boy it is hard to say now, there were so many phases and some things I bought were tools and jigs and even mistakes. But I think it must have been about $6000 in the end.

CC: Well that is not bad for a cargo e-bike with those capabilities. The Tern cargo e-bike [a long-frame cargo/shopper model sold by Citrus Cycles on Vancouver Island] is almost $6000 and yours definitely outclasses it as a cargo hauler.

GD: I do think that someone knowing what they were doing from the start, I mean if you were to build a copy of this bike, you could probably do it for $2500.

CC: Discounting your labour.

GD: Oh yes not counting the labour. But if you were making more than one, you would have jigs and you would pre-cut multiple pieces and I think you could put a frame together in a couple of days. And you would have a standard wiring harness. And so on.

CC: In most big projects like this there comes a moment when you ask yourself “Why the heck am I doing this, this is never going to work…” Did you have that bad moment?

GD: No, I never had one moment of despair. I had to learn everything, because I knew nothing about electricity, or batteries, or vehicle design. So knowing nothing, I was fearless. Everything is possible when you don’t know too much!

How’s It Working Out in Practice?

CC: So you are now riding the cargo bike regularly?

GD: Yes I use it all the time. It is my only vehicle.

CC: How many miles have you put on it?

GD: Well I don’t remember when I first rode it for real, but I have about 400 kilometres and more, and it was finished this summer so I have been riding it only a few months. I have had no problems.

CC: Has it lived up to your expectations?

GD: Yes, I think so. Well, perhaps I had to adjust my expectations a little.

CC: You thought it would go faster?

GD: Oh no, I would not want to go any faster! I do about 30 kph and that is plenty. No, originally I imagined that I could pick up a hitch hiker, I would be able to carry a passenger. Now I know that even at 48 volts that is not practical. Well maybe on the flat, but not up a hill.

CC: The handling and drivability, how satisfied are you?

GD: It is good actually, it corners well and handles nicely. But it is different from a bike or motorbike because there is no leaning into the turns.

CC: Because the frame is rigid, there’s no flex joint between bike and sidecar…

GD: Yes and that takes some getting used to. So you can’t corner as fast as on a bicycle or motorbike. And you have to shift your weight differently.

CC: Do you ever worry about the sidecar wheel lifting in a left-hand turn?

GD: Not unless I am going quite fast, but yes I am aware of that and sometimes I do lean towards the sidecar to make sure. On the other hand with the three wheels I can go as slow as I want without wobbling, and it is very stable when I have to pull over to let cars go by. Which on our roads happens a lot.

CC: And using the ferry, has that worked out as planned?

GD: Yes, very much. I am about the same footprint as a big touring motorcycle, I am less than 36 inches wide. Actually the width, it had to fit through the shop door so that was a hard limit on the width! So it is very easy for me to get a place on the ferry, and the bike travels free.

CC: Has it replaced your truck as you had hoped?

GD: Yes, absolutely I can do everything I used to do with my truck. Except of course a long trip but I hardly ever take a long trip. If I wanted to make a long trip now I would just rent a car. It’s cheaper than owning one all the time.

Would You Build Some More?

CC: Do people notice the bike? Do you get a lot of comments?

GD: It’s funny but some people don’t notice it at all. But when people do notice it, they are very interested and excited about it. More than one person has asked if I would build one for them.

CC: Sounds like a business opportunity! Are you interested at all in building more for sale?

GD: Oh no, not at all. I am not interested in making another one, not interested in selling them. I like to spin and dye wool, and that is what I want to get back to doing now that I have my e-bike working. I only built it because I could not find anything that met my requirements, not because I want to be a bike builder. But I have had so many comments on the bike I am sure you could sell maybe half a dozen of them just here on Cortes Island.

CC: So if someone did want to build them here on the island, you’d be happy to share your notes and drawings and let them copy your design?

GD: Absolutely, I would help them of course. It would be wonderful if someone wanted to do that.

CC: Have you documented your project online, in any maker fora or on Youtube?

GD: I have put it on Endless Sphere, which is a wonderful site for people building alternative vehicles. But it would be nice to have a YouTube video and I would like to make one, I have plans to do that.

[Companies mentioned in this article are not endorsed by Cortes Currents, nor does Cortes Currents receive any consideration for mentioning them in the course of this interview; recommendations are the personal opinion of Mr Dinim and are not reviewed or approved by Cortes Currents. Photo credits: G Dinim, D Clarke 2020]

2 thoughts on “Cortes Island Inventor Completes Cargo E-Trike”

  1. What a treat to see your latest project. I’m your fan since 1976 and always amazed by your work. Especially tbis since I have been riding and selling g ebikes for 4 years. Expect a visit ifrom me on an ebike in the Spring since we moved to Nanaimo recently. Or if you come through Nanaimo, hit me up.

  2. What an awesome project. It’s so rare to see someone with a vision. So many people just want what they see in a store. Nice to read about such a project – something that requires great patience, a learning curve, some trial and error. It’s not often we come across someone who has the idea, the imagination AND the determination to do the research and slowly bring a project into existence. I have to admit, I do know Gabriel, and he’s always been a real renaissance fellow……

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.