The Thoughts of Chairman Bill: The E-Bike Project

Got myself a new project - to build an e-bike.

I bought a 2nd hand Giant Talon mountain bike last weekend to use as a base. It's a sturdy bike of good quality and only cost me £190. Nice, fat tyres, front dampers that make it feel as if you're riding on air, Shimano gears and disc brakes all round with quick-release wheels. No.1 Son, who is into bikes and has a carbon fibre racer, checked it out for me before I bought it and declared it 'nice', which for him is a compliment.

Having done a bit of research, I gleaned the following:

The options are front wheel, pedal crank or rear wheel drive - crank being the most difficult and requiring some engineering expertise. I've gone for rear wheel drive.
You have to match the rear hub gearing to the wheel coming off the bike - usually 7 or 9 gear cogs; 7 in my case. Wheel size should be the same as the one being removed too - 29" in my case, which makes it a bit more difficult, as most kits are for 26" wheels, but I found the correct size.
You also need to ensure what's called the dropout is the same, which is the distance between the rear forks (if that's what they're called - my bike nomenclature being uncertain at present) that the new wheel fits into. It's usually a standard 135mm, but check.
Wheel hub power is for speed - there is a variety of wattages, going from 350 right up to 2,000 Watts. But, the higher the wattage of the hub, the faster the power drain of the battery and the more torque you generate, which can translate into either speed or hill climb ability, providing you have a beefy battery, which is added weight. I've gone for 1,500 Watts.
Batteries come in a combination of voltages and amp hours. Voltage must be the same for the hub, controller and battery. The greater the amp hours, the longer the battery life, which also converts to distance. I've ordered a 48V 20A with a continuous delivery (BMS) of 30A.
Your frame must be capable of containing the battery module - some of these weirdly sprung bikes just don't have the room between the frame struts, except for the smallest of batteries.

One thing you can't get, or at least not quite yet, is regenerative braking when going downhill. That's because the advantage is apparently outweighed by wind resistance. There are kits which purport to support regen, but they're simply added cost for almost no gain, although I'm sure the technology will improve.

Essentially it's as an add-on to the motorhome, which is a pain to move once we've set up camp, especially if wild camping, as you can lose your space if you leave it to go shopping or sightseeing. I was considering getting a trailer for the Triumph Daytona, but that's a very expensive option, not to mention the problems of reversing in narrow lanes with an articulated vehicle (a fixed motorcycle mount is a very, very expensive option, plus you need to ensure your rear axle can handle and extra 300kg load). An e-bike would be capable of being put on the existing bike rack (max capacity 60kg), but would be the equivalent of having a moped available for shopping trips.

I started off looking for a 2nd hand, ready built one, but they either look like Noddy bikes (the old folding Raleigh type), which aren't very cool, or are extremely expensive, or are underpowered. I spotted this rather nice one on Facebook Market, but the bloke wanted £1,600, which made me think I could do one much cheaper with a 2nd hand bike.

The colours are good and I particularly like the headlamp, which he constructed from a motorcycle headlight combined with a powerful LED torch. He used a new bike as the base and it's a 1,000 Watt jobbie with a reasonably big battery, hence the price. I spent hours chatting to him and he was a mine of information about the parts needed. He apparently spent £1,200 on parts alone, as you can probably tell;

I'm not going anywhere near as fancy as this, but I do like the electric setup, which is good for a 40 mile range. My cost for the kit is £640, split equally between the hub / controller and battery and is packs more punch than the one above. The delivery came yesterday, only 3 days after ordering it, and here's the bike and kit.

The triangular battery fits the space in the frame perfectly and the controller comes in a snazzy, waterproof pouch, which I can hang under the 45 degree strut, although I may go for a small carrier above the rear wheel. However, I thought I'd charge the battery last night as a preliminary, but the charger became very hot (67 degrees C) and there were no tell-tale lights on the battery indicating charge level, although it did charge. A missive has been sent to the seller, asking him to resolve the situation ASAP.

That said, there are cheaper alternatives...

The photo above is not my 'other' bike, but an example.

This little setup costs only about £80 with a kit from e-Bay - it's an 80cc, two stroke add-on for road bikes with a 2 litre fuel tank and, yes, I ordered one for my other bike and it's waiting to be fitted.

Not as environmentally friendly, but it does leave me open to choices and it's a technology I'm more familiar with. A good project to work on with No.2 Son, who has no idea of how an internal combustion engine works - not that it's something he will need to know for much longer. Decidedly uncool, but practical.

The petrol engine arrived Wednesday against a schedule of today - excellent service. Here's a photo of the engine balanced in position. I'll probably start work on it on Sunday. The fuel tank is black, but I'll spray that the same colour as the bike.

Making a start on the e-bike headlight, but will probably need to order another for the moped, although the fork mount isn't perfect, so I'll need to adapt the mount somehow for the handlebars; the mounts need a 90 degree twist adding to them.