Karon loves her Roberts bike but was rarely riding it, as her health issues made even the gentlest of uphill gradients very difficult for her. We had talked about adding an e-assist kit to the bike for a while, but she didn’t want whatever we chose to change the bike too much, or make it unwieldy. Big batteries and motors are heavy. In the end, I settled on a Swytch Bike kit. It’s a front wheel hub-drive kit with a smallish battery that fits to the handlebars rather that the rear rack or downtube.

The kit motor comes built into the wheel size you specify. You also receive the battery and cover (this version is the ‘Pro’ with more range), the battery handlebar mount and cover and pedal sensor along with plenty of zip ties and two instruction leaflets. Brake sensors and a throttle are shown on the Swytch website and there are connectors for both on the kit, but there doesn’t seem to be a way of buying them online without contacting Swytch.

Fitting the kit was straightforward and easy, though I did have to file out the paint from the dropouts on the bike so the axle would fit.

The pedal sensor assembly is very easy to fit as the magnet plate comes in two halves that fit together over the crank and are held firm by a metal ring, so there’s no need to remove the crank arm. The actual sensor is positioned close to the plate in line with the magnets with zip-ties and a sticky pad. I ran the wire up the underside of the down-tube, so it’s not too obtrusive.

The battery mount clamps to the bars close to the stem and has a strap to prevent the weight of the battery rotating the mount around the bars.

Once the dropouts had been filed, just a little, the wheel fitted well. The tire that came off the old wheel popped off the new rim but another 28mm 700c tire did fit and inflate without popping off the rim.

The ECO kit has a battery capacity of 5.2Ah (187Wh) and an expected range of 35km on medium power. The PRO kit has a battery capacity of 7Ah (252Wh) and an expected range of 50km on medium power.

There are five power levels and all will keep providing power until the maximum 25kmh/15.5mph legal (UK) limit is reached. This is different from other e-assist motors I have used, where each power level has a pre-determined speed cut-off, which increases with each power level increase, up to the maximum legal speed on the highest power level. Varying the speed cut-off to match the power level is more flexible in my opinion, and allows for easier power management and therefore more flexibility in optimising the range for each charge.

After trying the bike, Karon decided she wanted a throttle as hill starts were difficult in that you need to turn the pedals before the motor kicks in and on a steep hill, she would not necessarily be strong enough to get the bike started. It also makes pulling away at junctions safer, as you can get going and accelerate quickly.

The Swytch throttle is expensive and doesn’t come with the UK kit (as throttles are actually illegal in the UK). However, I bought one online which is essentially the same but a lot cheaper. I couldn’t use the connectors as they didn’t match so I trimmed the wires and soldered them together. There are only three wires and the colours used are similar in the kit and the third party throttle. I used a Minouri bar accessory bracket to position the thumb throttle in the best place.

We had obtained some inline brake sensors to cut power when braking, but in use Karon found she didn’t need them, so I put them on eBay. We also found that the motor/controller interfered with her wireless trip meter, so I moved the sensor for that to the rear wheel and positioned the display further back on the cross-bar.

For the power, the battery is quite large but I do like the way the controller is integrated into it. The kit is also very neat and it would be relatively easy to remove the battery and replace the motor wheel with the bike’s original, as there is a connector on the fork, near the hub. This would leave just the wiring and handlebar mount in place and quickly revert the bike back to almost its original state.

Compared to the 17.5Ah (630Wh) of the Hailong battery on our tandem, the 7Ah battery on the Swytch kit is pretty meagre. Our tandem covered 60 miles on full power before the Battery Management system started reducing power to the motor to protect the battery from draining completely. Using assist only on climbs when needed on the tandem gives us a range of at least 80 miles between charges, often more in ‘easy’ terrain.

With the Swytch kit, Karon estimates that each of the five battery ‘bars’ are good for about 4 miles, so the kit would deliver roughly 20 miles constant use. Obviously using it only on climbs will extend the range to the 30 mile figure quoted by Swytch.

In January 2017 I set about electrifying my HPV Scorpion FS20 recumbent trike. Trikes are great fun to ride, and comfortable too. A lower profile and recumbent position mean they are more aerodynamic, but the downside is their weight. For me, it makes any climb hard going, even pretty innocuous lumps can take some effort. Of course, you can grind away in an ultra-low gear and, with three wheels to keep you upright, you can go as slow as you need to.

After looking at the options of a wheel drive or crank drive, I opted for a crank drive. Wheel drive kits tend to be cheaper than crank drives, but I find the crank drive a more elegant solution. And, If I ever wanted to sell the trike, I could remove the kit, revert the trike and fit the kit to a different bike, regardless of wheel-size. A crank drive will only have a single chainring, but my trike had that already, so it meant I could retain all 27 gears – a 3-speed rear hub gear with a 9-speed cassette fitted.

A Bafang seemed to be the obvious choice. Buying from China, where they are made, is a lot cheaper than sourcing one in the UK or Europe – there are plenty of providers on Amazon but the disadvantage is delivery times are much longer. As I was a bit sceptical about buying direct, I ordered a kit including a 15Ah battery from Woosh Bikes in the UK.

The Bafang kit is very comprehensive and easy to install, thanks to the fool-proof connectors. Instructions are not really needed, which is probably a good thing, as there weren’t any. For those that are doubtful, there are plenty of videos on Youtube about how to install a Bafang…on an upright.

First job was the remove the current bottom bracket from the trike. And there I hit the only real problem I had. Even with the right tools, I could not loosen it, so took the bike up the road to my local bike shop, where they dealt with it straight away.

On my first ride out, the motor rotated within the bb shell, even though I thought I had it tight. That pulled on the cable and pulled the main connector apart, and I lost drive. It didn’t take long to sort out.

Since putting it together I’ve ridden several hundred miles without any real issues, though the connection (my extender) to the speed sensor became erratic because it had worked loose, so I soldered the joins rather than just wrapping them… something I should have done in the first place. For the larger cable extension I used plastic-housed screw connectors and wrapped all the connections in waterproof tape.

After coming back from a long tour of France I decided it was time to put a motor on the Pino. I had mulled it over for some time and, because a new ‘e-pino’ is horrendously expensive, I decided to fit a Bafang ‘Fun 8’ mid-drive motor. In the UK we are legally limited to 250W maximum power.

I bought the motor and battery together, from ‘Aliexpress.com’ and ordered it from China, as it’s cheaper than using a European supplier, but delivery times are longer. If you are in a hurry for the kit, a UK or European supplier will get it to you sooner.

The hardest part was getting the old BB out – it had been on the bike since 2011. I swapped the stock control display unit for a SW102 combined controller/display which is very small and sits neatly at the bar-end. I also had to fit hydraulic brake sensors (bought at the same time) and I fitted the plain, right-hand crank from a Thorn Tandem ‘Captain’s’ crankset from SJS Cycles. The total bill was around £700.

The Hase crank has a square taper axle – in what I call a ‘square, square’ pattern. The Bafang cranks supplied in the kit are ‘square, diamond’ pattern, so, in order to retain the Hase freewheel, you need to source a ‘square, square’ right hand crank. These are available as a Tandem Captain’s crankset from SJS Cycles. You will have to buy the crankset, as they don’t sell individual R/H cranks.

Extras

Pino update – fitting a second battery