I see a fast-growing movement to convert trikes and bikes to electric assist. There are good reasons, excuses and problems for the electric recumbent trike.
Good Reasons
I was working in Canberra and commuting 15km each way. Being neither fit enough nor fast enough to do this on my HP Velotechnik Gekko fx without assistance, I added a 250-watt Bafang crank (mid) drive system. I had to upgrade from a 4.5AH to a 17AH battery to make the 30+km with some reserve. So, good reason number one – repeated trips in limited time.
Other good reasons include riders with a disability and those that ride with faster groups on upright bikes.
Excuses
I must admit that when choosing an electric recumbent trike, I was also picturing the many rides where I was puffing and panting up a hill. At the same time, my slim partner zipped up ahead, seemingly without effort.
If I knew then what I do now, I would have changed the gearing. My partner would have still pulled ahead, but at least I would have arrived ready for the next challenge.
Problems
It is a matter of exercise. Riding a trike with an electric assist is much easier than walking. It is about as much work as spinning the pedals backward. The Shimano STEPS and the like mitigate this by reading the pedal pressure and providing assistance accordingly. Even here, the temptation to use maximum assist can be overwhelming.
I now use my trike for exercise and to ride new trails. For me, I think it is better to tune your trike to ride any slope with ease and without electric assist. There is less to go wrong and more to gain with a feeling of satisfaction at the end of the ride – all providing the gearing is modified to make the ride pleasant.
I have kept the Gekko, changing the gearing to ride with or without the motor. The power is there for when I get old and frail.
Rain can cause a problem. The external controller for hub drives does not like getting wet. I have also heard of crank drive systems flooding and frying. It is less likely with a trike where the motor is further off the road – unless you ride into a river. The Bafang unit seals well. I have ridden in heavy rain many times without an issue.
Problem three is weight. Another three of four kilograms can make it a lot harder to lift in or on a car. I am writing a series of articles here that will work for any weight of trike.
Then there is reliability. More complexity means more potential problems that are harder and more expensive to fix.
Next, crank drive units have one chainring making riding without power more difficult. This is why crank drives are often paired with 14-speed Rohloff hub gears. Rohloff makes a great solution if you don’t mind spending half as much again as you paid for the trike.
Lastly, we need to address cost – even without the Rohloff hub. Batteries are expensive and drive installation even more so.