A guide to ebikes

[keithmac]

virtually all e-assist use and external wheel sensor or and internal sensor .
fooling a unit by using an incorrect ( smaller ) wheel size will increase the top speed but the speedo will be incorrect.
I have seen someone fitting a 2-1 reduction on a rear hub to increase speed . I personally would fiddle the internal software and increase the cut off speed.

regards Emma

You'd need a larger wheel (greater distance traveled per revolution) if the limiter was based on wheel rotation speed.

 

[Drago]

Its getting harder now, and rightly so. Latest gen Bosch, Yamaha, Shimano etc can all detect dongles, and Suntour HESC+ is simply undonglable anyway. To change wheels size settings on the latest versions any of these now requires dealer software, which is strictly controlled and licenced, and anyone caught arsing about with it will suddenly find themselves stripped of the privilege. And qukte right too.

 

[CXRAndy]

Bosch gen4 have been reversed engineered to allow third party tuning. Yamaha motor too. I expect all current motors can be tuned for owners own requirements

 

[keithmac]

Thing with "tuning" them is it puts all ebikers in a bad light..

 

[Pale Rider]

Its getting harder now, and rightly so. Latest gen Bosch, Yamaha, Shimano etc can all detect dongles, and Suntour HESC+ is simply undonglable anyway. To change wheels size settings on the latest versions any of these now requires dealer software, which is strictly controlled and licenced, and anyone caught arsing about with it will suddenly find themselves stripped of the privilege. And qukte right too.

The likes of Badass say their latest dongle will work on the latest Bosch motor.

I've also ridden a Suntour motored Carrera on which the restriction had been removed.

It was a bit clunky, full gas as soon as you turned the pedals and no in between, but it went very well, more pokey than a similarly de-restricted Bosch bike.

 

[Drago]

You can't so much remove the restriction on Suntour, as to completely re-engineer the controller to allow it. Its easier to bin the controller and start afresh.

In the case of Suntour, the motor itself is specifically designed for the 25kmh cut off, not a fast motor simply screwed down to the limit, and isn't good for a lot quicker regardless of what you do with the rest of the system.

 

[TyrannosaurusTreks]

The likes of Badass say their latest dongle will work on the latest Bosch motor.

I've also ridden a Suntour motored Carrera on which the restriction had been removed.

It was a bit clunky, full gas as soon as you turned the pedals and no in between, but it went very well, more pokey than a similarly de-restricted Bosch bike.

I put a badass on my active line plus, bike shop recommended to calibrate it first which he did.
The bike runs really well & smooth, getting about 65miles on a charge.
He said he has reduced the speed limit to 20mph for some customers 🤪, I’m happy with 25-28 though😬.

 

[ericmark]

I seem to be in the reverse, bought an e-bike second hand, and only after getting it noticed it says 350 watt on the hub. I found the display allows some adjustments by pressing + and - together and have altered it to show MPH instead of Km/h. Other wise untouched.

It has 6 options for assistance, 0 is non, and 5 is maximum, setting to 1 the assistance seems to stop at around 4 MPH, but very little assistance given, at 2 however seems at low speed no difference in assistance to 5, it seem 3, 4 and 5 just change the point when assistance stops.

So whole idea of e-bike for me is to change from a push bike to pedal cycle. Without the motor I push the bike up the hills and free wheel down, seems no point having pedals they just bang ones shins when pushing it. Now I can pedal up the some hills, roads marked > I still have to push it on, and far too many roads marked > and >> around here.

It is a compromise, there are loads of pot holes, and I find suspension and large tyres help, it is less likely to cause a wobble with suspension. However that also makes the bike heavier. The same with gears, wife's e-bike has central motor so works through the gears, giving more help on hills, but only has 7 gears the front cog is a special belled design to go around the motor, but mine with hub motor can have 21 gears, so swings and roundabouts.

But the instructions with my e-bike 33 pages of them are rather lacking, it does not say how to even swap from Km/h to MPH, or how to adjust the cable disc brakes, having on non electric mountain bike realised the disc brakes would only slow me down not stop me when descending Symonds Yat while on holiday some years ago I am aware of the problems with cable disc brakes, loads about how the quick release clamps work, but nothing about brake adjustment.

The manual is a nice shiny paper clearly printed in bulk, but seems to be an OCR copy, "teRRain" not Terrain for example, so making reading hard, and nothing about settings for the electric part.

I think designed for USA market, so likely does need some tweaking for UK, since private sale not really an option to return it, and no idea where it came from, internet hunt I can find similar but non exactly the same. Larger motors, or controller mounted in different place, or different display module.

Don't get me wrong, it is a nice bike, and does what I want, and it seems the 17 codes can be set to make it street legal, reducing speed, power, and removing twist grip control. But every internet hunt seems to end up with USA sites, so I suspect many ride motor bikes thinking they are e-bikes.

 

[Drago]

Technically, if its a 350W motor it will never be street legal, even if it is set to deliver only 250W, in much the same way a 125cc motorbike can never be a moped even if it is resteicted to 30MPH.

Dibble are now wising up and looking for the compliance plate or decal on the motor, so while the odds are still very much on the outside of getting fingered the risk is real.

 

[Biker man]

A guide to the types of ebikes currently available in the UK

What is an ebike?
An ebike is a bicycle with an electric motor to assist propulsion. The motor is powered by a rechargeable battery, and its operation is governed by a controller.

What types are there?
Basically two, a motor which is bolted to the bottom bracket and drives the cranks, known as a crank drive. The second type uses a hub motor which is laced into either the back or front wheel, known as a hub drive.

What are the advantages and disadvantages of the two systems?
A crank drive rides more like an ordinary bicycle because it drives through the gears, which the rider uses in the same way as a push bike. A hub motor works more independently of the rider, so can feel more like (a very underpowered) moped.

There are two types of hub motor: direct drive and geared. The direct drive motors rotate all the time and drain pedal power energy when the system is not active. The better design is the geared hub motor which allow the motor to "freewheel" when not in use, which allows the bicycle to ride like a "normal" bicycle when electric assist is not in use.

The front wheel drive hub motors do exhibit some strange characteristic in wet weather on slippery surfaces e.g. drain covers where the front wheel can lose grip.

How long does the battery last?
Depends on the size of the battery, the riding conditions, and how much assistance you ask for via the controller.

Batteries are measured in amp/hours (Ah) and are usually around 10Ah or 15Ah. 20Ah batteries are available but are generally a lot more expensive. A 10Ah battery in favourable conditions could last 40 miles, but against hills and headwinds that could drop to under 20 miles. (The large capacity batteries are heavier and much more expensive).

What about throttles?
Throttles are legal in the UK but not everywhere in Europe, so most manufacturers don't fit them. Power is governed by fixed settings, usually about five, which the rider chooses via a button on the handlebars. The controller then varies the power delivery depending on how fast you are pedalling, and in the more advanced systems, how much torque you are applying to the pedals.

Throttles are available for some aftermarket kits. While it's tempting to want and use one, holding a throttle open for a long period of time is wearing, and some people find it difficult when they are pedalling as well. The use of a throttle does reduce the range as the throttle is "power hungry".

The majority of kits have a controller and pedelec controller, so the rider has a choice of using set power levels and / or the throttle. The more upmarket kits have a LCD screen with Mph, odometer, battery voltage and power setting.

The pedelec system cuts in after a couple of revolutions and cuts off when you stop pedalling and provides a controlled electric assistance.

What's the legal position of ebikes?
The EAPC regulations state that in the UK for an ebike to be legally a push bike it must have a motor of no more than 250 watts continuous power and the motor must cut out at 15mph (=/-10%). The speed cut out is not negotiable, the watt rating is more complex because all motors deliver more peak power when the controller demands it. There are other regulations regarding braking efficiency etc. and the regulations can be found online.

Nearly all complete ebikes sold in the UK are UK legal. The position is different with aftermarket kits where there are lots of higher power motors on sale. I've not heard of anyone being prosecuted for using a high power kit, but legally they are not bicycles, so cannot be used on cycle paths and should have a number plate, and insurance.

Some ebikes with legal motors can be derestricted - the 15mph speed limit removed. This makes them illegal and often doesn't help a great deal - the motor is tuned for torque, not speed, so provides a lot less assistance the faster it goes.

How much do ebikes cost?
Anything from £500 to £5K+. As with ordinary bicycles, you get what you pay for. The motor and battery are heavy metal and valuable, so make up £500 or more of the cost. On a £650 ebike, the bicycle part will be cheap and nasty. Paying more than £1,000 will get bike components of medium quality.

The low cost ebikes use sealed lead acid (SLA) batteries. These are heavy and despite the rating of the battery the range is limited due to the construction of the battery at their 1 hour rate. Nicads were used in some early ebikes, again old technology and suffer from "memory problems and premature failure". The current Models use mainly Lithium, LifePO4 or LiPo batteries and further variants are now in production.

Some of the low cost ebikes use brushed motor technology. These motors are heavy and do not produce as much power as the later brushless motors.

The controller and motors are not interchangeable between these two systems

What about converting my bike?
A good option if you are reasonably competent mechanically and electrically. Converting enables you to choose the bike and the motor/controller/battery combination - handy if you have specific needs. It can be a bit cheaper, but a quality battery is about £300 and a hub motor £100+. Add a controller and a few bits and pieces and the parts bill will come to around £500. (Fitting a front hub motor to alloy front forks IS NOT RECOMENDED).

Crank drive kits are more expensive, but simpler to fit because there's no messing around with lacing a wheel, and the wiring is more straightforward.

Most kits come from China and quality is variable, some very good, others poor. BMS supply some good quality kits but beware the lower prices, once import duty, UK VAT and carriage is added to the price it does mount up. In most cases the duty is payable to the courier before delivery.

What's not to like about ebikes?
They are all heavy - 20kg+ - so the cycling experience is not as pure as on a push bike. The weight also means they are hard to pedal unassisted, which can be a problem if the electrics fail or the battery goes flat.

Another disadvantage is the weight makes ebikes unwieldy at A gates and other restrictions. Lifting one on to a train, up stairs or car rack is hard work.

Fixing a puncture is more complex on a hub drive - no quick release and the motor needs to be disconnected. Less of a problem with a crank drive, but there's still the weight to contend with. (There are some tubes available now that are made to fit without removing the wheel from the bike).

Hub drives torture spokes, so breakages are more common. That can be sorted by a properly built wheel, but as with ordinary bikes, getting one of those can be difficult.

There is hostility from some push bike riders - most ebikers will have been called 'cheats' more than once, but in reality ebikes fill a gap in the market that allow the not so fit to enjoy a bike ride without the effort of a convention bicycle.

(Adding a e-motor to a trike transforms it and makes it easier to ride uphill, It also helps with touring trikes that are laden with camping equipment etc.)


The above is intended as a general guide and is accurate as far as I am aware. Specific queries are probably best dealt with in separate threads where I - and others - can provide recommendations and opinions.

The website that caters solely for electric assist pedal cycles is the pedelec website.

The UK EAPC regulations are in the process of being revised. The 40kg for cycles and 60kg for tandems and trikes has been lifted and Electric assisted pedal quad bikes are being legalised.

Note: Thanks to @voyager for additional supporting information.

Hi I found that very interesting I used to have a hub ebike and loved that zooming off once you start peddling .The bike I have now is a mid drive with plenty of NMT for the hills around here and I love the hub gears I do miss the hub drive do you know what the highest NMT you can get on a hub bike regards.

 

[Pale Rider]

Hi I found that very interesting I used to have a hub ebike and loved that zooming off once you start peddling .The bike I have now is a mid drive with plenty of NMT for the hills around here and I love the hub gears I do miss the hub drive do you know what the highest NMT you can get on a hub bike regards.

I'm guessing by 'NMT' you mean torque, as measured in Newton Metres.

Hub motor are commonly rated for power in Watts.

UK road legal motors are nominally 250W.

Chinese retailer Blue My Sky sells higher rated motors, including an 800W one.

I could only guess at how much grunt that motor would provide, but I reckon it would feel great deal more pokey than a 250W motor.

https://bmsbattery.com/38-rear-driving

 

[Biker man]

I'm guessing by 'NMT' you mean torque, as measured in Newton Metres.

Hub motor are commonly rated for power in Watts.

UK road legal motors are nominally 250W.

Chinese retailer Blue My Sky sells higher rated motors, including an 800W one.

I could only guess at how much grunt that motor would provide, but I reckon it would feel great deal more pokey than a 250W motor.

https://bmsbattery.com/38-rear-driving

Hi yes a happy medium would be better.

 

[Drago]

Why? I'm 19 stone and a 250W, 600NM motor moves me about quite adequately.

If you want more, they are freely available legally and we've already provided you with a link to sellers in the other thread.

 

[ericmark]

Why? I'm 19 stone and a 250W, 600NM motor moves me about quite adequately.

I have found the mid motor 250 watt also ample at 22 stone, however the hub motor seems to reach a point where it starts to lose torque, if I can maintain around 6 MPH it works well, but as the speed drops below that point the motor seems to reduce the torque delivered and quickly it reaches a point where it overloads and cuts out.

Lucky not too many roads where the hills do reduce my speed to under 6 MPH, but one of them is the last 1/2 mile to home, I have to stop at the grave yard to allow both me to catch breath and motor to cool before doing last little bit home.

Also at steep junctions the mid engine helps as soon as you start to pedal, but the hub needs one to do a few yards before it kicks in, lucky my bike has throttle enabled, bought second hand and to start with it was permitted, new bikes throttle must deactivate at 4 MPH.

I have tried using the throttle or walk assist on the mid engine bike, yes it works, but the control is not easy to use, need to push a button, and it seems torque is limited, as yet not tried it on a flat road to see if it would allow one to travel at 4 MPH without pedalling, but to assist at junctions not required anyway as motor kicks in faster.

 

[Drago]

That depends on the hub motor. Direct drive ones may well indeed struggle at low RPM outside of their efficient operating range, but many hub jobs are geared and do very nicely from low speeds.