Electric Conversion Kit, Which to choose? Compatible with folding bikes?

[DCUK6]

Hi,

I've just started a hunt to find either a electric bike or a conversion kit for my existing bike.
My budget is around £700 which means i could afford some bikes but the quality or perfomance is a bit pants..



I have a few questions that im hoping someone can answer for me.


1. I currently have a 26" mountain which should support all the kits and have amost

narrowed down to two kits which apart from the battery seem pretty much identical.

Both use the 36v 250W Suzhou Bafang 8 FUN Brushless motor which is supposed to be brilliant for using with a different controller which increases the wattage when we go riding through the forests.
The main use for the bike however will be commuting to and from work and around the city.


8Funbike has their kit for £425.99 with a 9ah bottle battery,
8F26F36B | 8Fun 26" Electric Bike Conversion Kit | 36V 250W Motor, 36V Li-ion Water Bottle Type Battery with Panasonic cells

ALIENbikes has their kit for £549 with a 10ah brick battery
Electric Bicycles - 36v Road Legal Kits £549

Is there something that im missing to cause the price difference?
Are these the freewheeling motors so make it easier when the battery runs out? Reading up it looks like they are.​

2. Im having real trouble finding batteries for these kits, or any bike really. Does anyone know of a supplier of both bottle and brick batteries?

3. I will be looking in the future to purchase a folding mountain bike to make things easier and would mean i could drive to work on the cold mornings and spend the rest of the day on my bike.
Are these cits compatible with bikes such as
http://www.argos.co.uk/static/Product/partNumber/3321377.htm?CMPID=GS001&_%24ja%3Dkw%3A{keyword}%7Ccgn%3Apla%7C%7C3321377%7Ctsid%3A11677%7Ccn%3Apla%7C%7C3321377%7Cmt%3A{MatchType}%7Ccrid%3A14542145259
or 26SF02BL | Ecosmo 26" Dual Suspension Folding MTB Mountain Bike | This quality folding bike is an ideal companion for your life, Fold up size is 95cm(L)*33cm(W)*74cm(H), easily fit your car boots. Really easy to assemble.
?

Last but definatly not least.

4. When my aunt comes down we sometimes head to the new forest for a ride, and although i hate to admit it she is fitter than me.
I Would like to increase the power during this time and have read only that a change on the speed controller would be needed, is this the only thing that needs to be changed?
How far can the 250w 8fun motor be pushed? On another forum i read that one person ran 1000w continuous for 2 years with no problems. I dont really want to go that extreme but 350w would be good and would mean i wouldnt have to get a mahusive battery.

many thanks for your time.

 

[RobF]

I can't answer your technical questions, but a folding bike for £125 is unlikely to make a good donor bike, or be a good bike at all.

Avoid.

 

[DCUK6]

I can't answer your technical questions, but a folding bike for £125 is unlikely to make a good donor bike, or be a good bike at all.

Avoid.

Yeah, havnt really done any research into them yet. It was just because i was on the website at the time.
Probably be a good couple of hundred for a lighter weight one.

 

[103Alex1]

Yeah, havnt really done any research into them yet. It was just because i was on the website at the time.
Probably be a good couple of hundred for a lighter weight one.

It might also be a bit tricky to fit a battery on that bike unless you carried it in a backpack ? Do you definitely want a folding full-sus MTB for off-roading or would a folding hardtail do that would fit in a hatchback easily with the seats down / in an Estate ?

 

[DCUK6]

It might also be a bit tricky to fit a battery on that bike unless you carried it in a backpack ? Do you definitely want a folding full-sus MTB for off-roading or would a folding hardtail do that would fit in a hatchback easily with the seats down / in an Estate ?

Do you mean something like this?
Dahon Espresso 20" Folding Bike 26" Wheel | eBay
Quite hard to get a decent one and probably looking at about £700. Im now sure about the traditional folding bike looks. Think i would get a bit of stick riding one.

Just had a reply from 8funbike and their kits arnt compatible with either of there MTB bikes. I guess its because they use the bottle battery design which would have nowhere to go on the full sus bikes on their site.

One advantage the alien kits have is that the battery goes on the back so probably would be compatible.

 

[Deleted member 4366]

It's not worth putting a 250w kit on a bike unless the bike is something special. You can buy a ready made electric26" folding bike with full suspension for £499 on Ebay. While you're there, check out the Burisch electric bike. Think about the Woosh Sirocco sport or check out some of the cheaper bikes on the links to the right.

Build a bike with a kit if you want high power, light weight, high spec., otherwise buy a ready made.

 

[DCUK6]

It's not worth putting a 250w kit on a bike unless the bike is something special. You can buy a ready made electric26" folding bike with full suspension for £499 on Ebay. While you're there, check out the Burisch electric bike. Think about the Woosh Sirocco sport or check out some of the cheaper bikes on the links to the right.

Build a bike with a kit if you want high power, light weight, high spec., otherwise buy a ready made.

The Sirocco looks pretty good, it has the motor i was after and also the 10ah battery in the Sirocco-x.

Not bad, will take a look through the rest of the features in the morning. The only downsize is the size of it.

Is the only difference between the sport and the lx the battery do you know?

Are kits only worth putting on racing bikes that have carbon fiber etc and lightweight?

Just have to decide now if a traditional shape folding bike with the smaller wheels is better or worse, i know it wont do the forest stuff but thats not very often.

The sport is 21kg, the Sirocco x is 24kg which is the same as the traditional folding shape bike. so its basically just the size.

Woosh bikes are 3-6kg lighter than the 8funbike bikes.

 

[103Alex1]

Are kits only worth putting on racing bikes that have carbon fiber etc and lightweight?

I'm sure others will note the exceptions and provisos, but on the whole my understanding is that carbon frames throw up a whole load of other issues - easier to work with dropouts on an aluminium frame for example. Plus an 8kg bike doesn't really need the added weight of a motor and battery. They're not ideal to work with and if you damage or drill them they lose their inherent value pretty fast. There are plenty of lightweight aluminium bikes or ones with carbon forks if you prefer that. The weight differential between a carbon bike and a really nice aluminium-framed one with lightweight spec is usually only a couple of kilos over the whole bike.

Just have to decide now if a traditional shape folding bike with the smaller wheels is better or worse, i know it wont do the forest stuff but thats not very often.

The sport is 21kg, the Sirocco x is 24kg which is the same as the traditional folding shape bike. so its basically just the size.

Woosh bikes are 3-6kg lighter than the 8funbike bikes.

I would go look at those bikes if you can. If you still want to do a folder kit with a higher-powered motor I looked at this bike as a possible donor before deciding against a folder completely.

The idea was simply to have a frame that folded to allow a bike to be more easily loaded in a car boot should the need arise. It wouldn't really be suitable for taking on a train. I'm very tempted to buy it as a donor for kit test project(s) at that price but have my hands full (and bank account depleted) at the moment ... plus I still haven't found an affordable carbon road bike to satisfy my alter-ego when I'm not getting muddy, going to the seaside or dealing with what I already have !!

RARE BMW FOLDING MOUNTAIN BIKE NICE GREAT BICYCLE HIGH SPEC | eBay

It's different, and you could fit a nice 350W / 500W motor and a decent battery to it. Would probably be quite heavy finished for getting in and out of the car boot but it would feel like riding a regular bike rather than a folding bike.

It's actually a Montague frame from early folder project they did with BMW.

 

[Deleted member 4366]

Everything's always a bit more complicated than it first appears. Many bottle battery types have integrated controllers that are very difficult to change. You've figured out about motors. You can usually get a lot of extra power out of them by changing the battery and the controller, and often a bit more climing power by adjusting the controller as long as it's seperate annd accessible.

Maybe you should go back to basics and make a list of your requrements and youy budget. Then people can advise on the various options.

 

[DCUK6]

Everything's always a bit more complicated than it first appears. Many bottle battery types have integrated controllers that are very difficult to change. You've figured out about motors. You can usually get a lot of extra power out of them by changing the battery and the controller, and often a bit more climing power by adjusting the controller as long as it's seperate annd accessible.

Maybe you should go back to basics and make a list of your requrements and youy budget. Then people can advise on the various options.

Thanks, have to say I cant see controllers on these bikes. I have sent a email to woosh asking about their sirocco.

My main requirements are:

Capable of riding without the motor switched on
£700 budget
Able to replace controller with 44-48w controller
250w road legal
Befang motor preferred.
Larger battery, 16ah would be best for of road use with the upgraded controller.

I took a look at some of the folding bikes with 20" rims today and they dont look to bad so would now like to compare the best of both. I'm guessing the 20" wheeled bikes won't go as fast under pedal power but probably makes the motor have a easier time.

 

[Deleted member 4366]

Thanks, have to say I cant see controllers on these bikes. I have sent a email to woosh asking about their sirocco.

My main requirements are:

Capable of riding without the motor switched on
£700 budget
Able to replace controller with 44-48w controller
250w road legal
Befang motor preferred.
Larger battery, 16ah would be best for of road use with the upgraded controller.

I took a look at some of the folding bikes with 20" rims today and they dont look to bad so would now like to compare the best of both. I'm guessing the 20" wheeled bikes won't go as fast under pedal power but probably makes the motor have a easier time.

You've sort of jumped to the end instead of starting at the beginning.
Do you have shares in SZ Bafang or is there another reason that you can't use a better one?
To make it a bit simpler for you, which I apologise for not doing sooner.
How fast do you want to go?
How far do you want to go?
How much do you weigh?
How hilly are your rides?

You'll struggle to find any legal electric bike in this country. The only thing you can do is minimise the risk of prosecution.

 

[DCUK6]

You've sort of jumped to the end instead of starting at the beginning.
Do you have shares in SZ Bafang or is there another reason that you can't use a better one?
To make it a bit simpler for you, which I apologise for not doing sooner.
How fast do you want to go?
How far do you want to go?
How much do you weigh?
How hilly are your rides?

You'll struggle to find any legal electric bike in this country. The only thing you can do is minimise the risk of prosecution.

no, I've just only read about how much the befang can be over powered and have found posts of them being able to take alot over 500 watts, although i would like something that could take a 44v battery with a change of controller.
If there are others then il be happy with them too.

I would be happy with around 18mph but have read on another forum that they have had a 250w up to 21mph but I think this would just murder the motor.

The longest trip commuting around normally is 25 miles in a day with the most being 30-35.

Currently weight 9 stone 11, or 62kg, or 137lb.

I will be cycling around Portsmouth area so it's pretty flat everywhere.

Budget is around £700 but there's always another month savings to add to it

 

[Old_Dave]

So it's feb / march then


Sent from my iPhone using Tapatalk

 

[Jeremy]

My advice would be to pay very little heed to the mythical power ratings that these kits and motors are blessed with. The smallest motors available (like the little Q100) will deliver over 500W continuously on 44 to 50V on the level.

Although it takes a bit of getting to grips with, the simulator on the Grin Cyclery site (ebikes.ca Hub Motor and Ebike Simulator) is pretty useful when it comes to working through options. For example, a fast wind Q100 running on 48V with an efficient 25A controller in a 20" wheel would give you over 23mph on the level, and would still climb a 5% gradient hill at 10mph (and around 300W output) forever without overheating. This is for one of the smallest, least powerful, hub motors that are currently available.

 

[Deleted member 4366]

I've got a feeling that you didn't answer the question about speed honestly.
For your weight, distance, quoted speed and terrain, a nominal 36v motor should be sufficient. For your range, it can be done with a 36v 9ah battery if you wanted to pedal a bit, but a 12ah would be better in case of wind. If yo wanted to go at 18 mph average without pedalling hard, a 15 ah one would suit.
Some of the 250w Bafangs come in 250rpm versions, which would give about 20mph or more. The Ezee kit has a motor that can do 20 mph AFAIK. Any 201 rpm motor will run atabout 250rpm with a 44v battery, and proportionally more at 48v, although you could just use a 323rpm one at 36v for the same result, so don't get hung up on voltage.

As Jeremy says, all the motors can take a lot of abuse, but what they don,t like is struggling under load up a hill, and stalling is a definite no no; however, with your weight and terrain, that shouldn't be aproblem.

 

[DCUK6]

Yeah, i would like it to go as fast as possible as most peole would, 20 or so would be good. That was why i eventially wanted to up the power a bit but i was just concerned about blowing it so thought 18-20 was more safe.

I do want to keep it 250w for certain so if you ever do get a officer walking past the bike it clearly shows 250 on the label.

Having no experience on the 20" folding bikes im not sure what the maximum peddle speed would be. If you could only peddle to say 16mph could the motor take you up to 20 on its own and keep you there?

As you said, im thinking of a larger battery for a couple of reasons, the first being its built to fit the larger batteries so the zippo 8000mah batteries should hopefully fit in, and secondly i could buy a cheap 36v controller before i upgrade the battery that allows more amps through although i havnt got my head round what this will do yet completely, in my head im thinking it will allow you to get more toque but no more top end speed. i've just read it somehwere.

As you can tell this is all very new to me and my electric skills arnt the best.

The only problem is finding a bike thats fitted with the larger battery, juicy bikes do them but it works out mega money. The wosh sirocco 2 has a 16ah battery and would probably be the one i would go for if i had to decide on a full size bike right this second. I am getting more and more tempted by the 20" bikes though.

If the motor could get a 20" bike to 18mph, it should technically get a 26" to 22-23mph ish but it must loose the acceleration because of the bigger wheel, would they both run around the same speed because of the bigger tyres giving you less torque to get to the higher speed and the smaller wheels allowing it to spin slightly faster as its easier? The simulator doesnt show this mind.

Its a whole new world to me .

 

[Deleted member 4366]

With the wheel size/motor speed situation, the problem is that you want the motor tospend most of the time in its high efficiency zone. When the motor runs at full throttle and at less than half it's top speed, it starts to become increasingly less efficient. It therefore gets hot and uses two or three times the amount of battery as one running in its sweet zone. That's why it's important to choose the right motor speed. Most of the ready made bikes are designed to run at about 17MPH max, so efficiency doesn't drop off until it gets below about 10 mph.
Sent from my GT-I9100 using Tapatalk 2

 

[patpatbut]

Hi there

First, I am not an expert here but I have made my own conversion with the helps here

The first conversion was Dahon Jack D7 2011 folding bike. I must say it is a perfect bike for conversion

I am using SWXH motor 36v 12ah lifepo4 and it can go 18mph throttle only but I restricted it to 15 mph for legal reason.

For the conversion, no filing of the dropout is needed the motor fits perfectly to the rear. So basically plug and play.

Total spend is around 190 for swxh kit + 300 for battery + 180 for the bike + 50 tools etc
= £730 (all included duty and deliveries)

Let me know if u need more info

Regards
Pat

 

[Jeremy]

I do want to keep it 250w for certain so if you ever do get a officer walking past the bike it clearly shows 250 on the label.

That's pointless, as the law requires a data plate on the bike, not a meaningless power label on the motor. The law in the UK is 200W, not 250W, anyway.

EU approved ebikes are nominally rated at 250W, but they aren't strictly speaking legal in the UK yet, and the way the EU rating assessment works ebikes of 500W or so can be declared to be 250W as far as their regulations go.