Electric Bikes – Yuba Mundo eV4 – delivery and build


OK, it all happened today! I rang Bicycle Junction just before midday, and was told that my motor kit had just arrived, and I could pick up the bike!

At just after 12, I drove into Wellington to the bike shop, and took delivery of bike and Lekkie motor kit. I hung the bike off the back of the Honda. It wasn’t as bad as it looks in the photo, it only stuck out about 200mm each side!

I got home about 1.10, and spent a happy 30-40 minutes unboxing the motor and battery, and trying things against the bike to see if there were any show stopping problems. Only one definite problem popped up, the speed sensor wire was designed for a normal bike, so was 30cm short to reach the back wheel of the cargo bike. The rest of the wiring looked a bit short, but until I actually put everything on the bike, it was hard to be definite. I attached the battery bracket to the downtube, and put the battery on charge.

Lynn cam home and I made lunch, and rushed back downstairs about 2:45 and started work.

First, remove the original cranks, chain wheel and bottom bracket, and remove the pedals from the cranks.

Check the bottom bracket tube for interferences inside, and then slide the motor through the tube. Add the left hand side bracket, which sort of completes the construction of the motor, gearbox and bottom bracket. Lift motor into position, and tighten up bottom bracket nut and two setscrews. Add the pretty locknut to finish the job off.

Around the other side, attach the supplied chain ring (46 teeth), as the original chainring (38 teeth) had a different mounting hole pattern. Add the chain guard, cranks and the original pedals.

I connected the motor to the battery bracket, and the wiring harness for the rest of the peripherals to the motor, and roughly cable tied it all in place.

In the end I had to remove both handgrips from the handlebars so that I could fit the front brake lever on the right, and the control panel, thumb throttle and rear brake lever on the left. These 4 items all connected into the harness with waterproof plugs and sockets, and all the wiring was just long enough!

At this point I replaced the battery on the bracket, powered up using the battery switch, and pressed the Mode switch for 2 seconds on the controller, and the control panel lit up! I did some simple tests on the motor, throttle etc. and adjusted the brakes, and took it for its first test ride at about 5.00!

And that just left the speed sensor. As this is a long tail cargo bike, the wheel is another 30cms or so back from the bottom bracket, so the normal sensor cable is about 30cms short! There are extension cables available for a few dollars, which are exactly 30cms long, but all the suppliers I checked out were out of stock, so I found some matching 3 core cable, grabbed my soldering iron, and spliced a 30cm extension into the existing cable, fitted the speed sensor and connected it all up. An LED on the speed sensor lights up when the unit is powered on, and flashes each time the magnet passes, so testing was quite simple, and when the rear was lifted and the throttle used to make the wheel turn, the speedometer registered.

By now it was 6.00, and dark, so no more test rides for today.

Tomorrow I will find some mudguards and fit them, and at the same time take it for a long test ride, which I will report on tomorrow.

I have found some reflective vinyl from one of my suppliers which almost exactly matches the colour of the bike, so I will order some of that to do the signwriting in.

Now the real fun starts – tuning to my needs and customising it to look good for the business!


Posted in Electric Bikes, Yuba Mundo eV4

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