Hello all, we (my wife & I) are looking for a couple of foldable ebikes and are, of course, overwhelmed by the choice.
We don't care about how fast it will go, nor do we care about throttle-only performance (we want to peddle), but we do care about making light work of hills. We will be carrying them in the back of our motorhome and want to have a nice, leisurely experience exploring local areas in the UK and Europe as we are no spring chickens.
Problem with most reviews is that everyone seems obsessed with raw throttle power (I thought throttles were illegal?).
So my question is - could anyone recommend an up-to-£1k-ish-but-could-go-a-bit-over foldable UK legal ebike whos selling point is its great at assisting up hills? Personal experiences rate higher than youtube influencer videos...
My shortlist is a long as your arm but made with very little references to the features we want (fido d4s, ewenge c20pro, ado af20, wooshbikes rambletta, ......)
Thank you all (and I will continue to read existing posts on this site, it's where I got the wooshbikes and fido bikes from).
Firstly, disregard anything that anybody tells you about their experience or recommendation, when they don't mention their weight/mass, the precise incline of their hills and their circumstances, in particular, their fitness and the amount of riding they do.
Secondly, all motors make approximately the same power. There is no such thing as a 45 nm motor. The amount of power or torque you get to climb a hill depends on the control system and battery, not the motor.
There are four significant characteristics that determine the hill-climbing ability.
1. The current that the control system feeds to the motor. Torque is directly proportional. No seller or manufacturer tells you the current nor the watts, but they're all pretty similar in the range 12 to 15 amps, so not a big difference in practice.
2. Battery voltage. Again, torque is more or less directly proportional. Nearly every bike is either 24v, 36v or 48v. 48v will give double the torque of a 46v system, do choose a bike with that if you want the most torque
3. Wheel size. For the same motor and control system, the smaller the wheel, the more torque you get.
4. Mass or weight. The lighter the combined mass of the rider and bike are, the easier it goes up any incline. With a rider of 80kg and bike of 20kg, each 1kg added requires 1 % more power to go up a hill at the same speed. You can save weight by not wearing heavy shoes or clothes, and not fitting accessories to the bike. Beware that most light bikes get their light weight by having a small battery, that might be limited on current because of its small size, as well as not being able to take you far.
Summary
An average 36v bike with average 15 amp control system and 20" wheels can get an unfit 80kg rider up all but the steepest hills (20%+). If you're 100kg or more or if you have exceptionally steep hills, you need 48v, of which there are many on Ebay. Avoid 24v bikes.
Other considerations
Many of these sub £1000 bikes have some cost cutting in their choice of parts. The things to look out for are
1. Gearing. Often the gearing is low because of the cheap gears and small wheel size. That's great for going up hills, but very inconvenient going down. Look for one that has 11 or 12 teeth on the top gear unless the chainwheel is very big (52T)
2. Disc brakes are always better than rim brakes on these bikes. Rim brakes are very hood when you try them out, but need constant attention to keep them good, and even then, they can be very grabby, so not good in an emergency.
3. Battery size. Multiply the volts by the amp-hours to get watt-hours, which is the currency you have to deal with. On those sort of bikes, 300wh will get you 20 miles if you put in some effort. Therefore, 450wh will get you 30 miles, etc. When the seller tells you it's a 20 amp battery, they mean 10Ah, not 10A, so a 36v one will be 460wh.
4. Control system. If you do get a bike that can provide high torque, it can be very jerry at low speed. The only way you know if this is OK is to try it. Some bikes have better control systems than others, but didderent ones suit different people.
5. Battery in the frame. Many of these sort of bikes have the battery in the main frame tube. Look out for ones that have a connector in the folding hinge, which is most of them. That connector can give big problems when the hinge wears or isn't aligned properly. Some are better than others. Rack batteries and batteries behind the seat tube are generally more reliable and easier to deal with.
I didn't mention crank-drive bikes because they're mainly above your price range, but also I think the simplicity of a hub motor in that type of bike is a much better solution, especially as you can easily get enough torque for anybody when you have 20" wheels.
Finally, the last and maybe most import point as many people find out sooner or later. All ebikes need something fixing sooner or later. Some bikes have closed systems, so you have to buy the parts from them or worse still get the bike fixed by them. The main problem with closed systems is that it's not easy to figure out what's wrong. The cheaper unbranded bikes tend to have open systems with standard parts that are easy to obtain and easy to diagnose and fix yourself. If you're going to rely on a dealer to fix your bike, you must buy from a local dealer whatever they have, otherwise fixing your bike will develop into a big problem. If you want to fix the bike yourself and have the cheapest solution, make sure you buy a bike that has standard electrical parts, that rules out some Halfords bikes, Decathlon bikes and many bikes from local dealers.
