Which ebike kit should I get?

[acueductomtb]

Hi All! re-posting this because I used the Electric Bikes forum and its not ideal. I really appreciate your help!

I wanted to try one a conversion kit but It seems they are not that popular. At least for me, I don't spend a lot of time in front of the computer. All I'm getting from a Google search is DIY kits with big batteries and a lot of cables, In Aliexpress there a lot of them! They are really cheap so Im tempted! Have anyone tried one of those?

I was looking for a very lightweight front hub motor. If it is Pedelec, I don't need the battery to be that big. My commute is mostly flat so....

I found this one too: https://www.swytchbike.com/ but is a pre-order which is not ideal. Has anyone had experience with this one?

@sjpt kindly suggested this:

"Look at Yosepower https://yosepower.com/ or Woosh https://wooshbikes.co.uk/ for kits.

A lot of the cheap kits have direct drive motors that are heavy, inefficient, real batter chewers, not that good at climbing hills, and almost always illegal to use without license, insurance, etc. If you look at the threads here you will see many have been tempted by the cheapness and the apparent high power and then regretted it."

Thank you

 

[Nealh]

Many use kits for bikes but most aren't tailor made for all circumstances like light motor or small capacity battery.
For lightweight motor you have to have a light bike and not be overly heavy, for a small battery you can use 5 or 6ah but need 20a + rated cells for small capacity.

 

[acueductomtb]

Many use kits for bikes but most aren't tailor made for all circumstances like light motor or small capacity battery.
For lightweight motor you have to have a light bike and not be overly heavy, for a small battery you can use 5 or 6ah but need 20a + rated cells for small capacity.

So you think it is better to get separate components and ask for some service to help me install it?

My bike is super light, it is an old school Peugeot bike that I love!

 

[WheezyRider]

So you think it is better to get separate components and ask for some service to help me install it?

My bike is super light, it is an old school Peugeot bike that I love!

I would look for a kit with a Bafang or MXUS motor, they have a known track record and you can get spare parts. Usually there are kits with the motor and controller/brake levers, pedal assist sensor, etc without a battery and then there are all in kits with the battery included.

Yose Power stuff is generally ok, but I am not overly impressed with their battery packs, although they are probably representative of what is available on the market in terms of mass produced low cost packs. Sometimes they don't have 250W models (UK legal) available on their site. At the moment they only have 20 and 24 inch kits available in the 250W rating.

What is your wheel size?

Are you sure about having a front hub? They have some advantages, like being easier to fit/sort out punctures, but unless you have a good tyre on the front, you can get wheel spinning when starting off and loss of traction in bends. In the wet/on ice this can be a big problem.

Personally, I would not go for less than about 12Ah for the battery and preferably 15Ah. These quoted values are if you completely ran the pack flat at a low discharge rate under ideal conditions. You will be lucky to get 80% of the quoted rating. Plus, you don't want to be discharging the pack to near empty on a regular basis, or it won't last long. And as Nealh says, drawing 15A from a 5 or 6Ah pack needs special cells with a lot of oomph, or they will overheat and fail, or the voltage will sag so much the controller or the BMS will cut the power. I think you will find once you get your e-bike set up, you will want to go further and further, so you may as well get one larger than you think you might need. You'll commute to work one day, then realise you need to go into town, then go somewhere else etc...you don't want to get stranded miles from home without power. Also, you might like to go on longer trips at the weekend.

If you hammer an ebike, expect to consume about 0.5Ah per mile or more. If you go steady and don't have to stop start you can reduce this to about 0.2Ah/mile and less, depending on how hard you pedal.

 

[Nealh]

Yose are ok but there are better lighter motors and electronic kits available, you only need 10,12 15ah or more for longer 30mile rides. Most of these batteries use poor or mediocre cells and a bespsoke 2p battery using something like HG2 or VTC5/6 cells would out perform them on discharge characteristics except the range part.
For a bike ridden locally or only needing about 10/12 miles range for commuting to keep the bike as light as poss the a small 5/6ah battery and motor makes sense even more so if no big hills are involved.

You can get sub 2kg for front hubs pair it with alight 10s2p or 12/13s 2p cell pack weighing sub 1.5kg if you fit it in a small saddle type tool bag you would have the best part of a lightweight kit, the weight saving alone could be about 4kg to start with.
The lightest conversion you can get is sub 2kg but that is for a friction drive with about 12miles range with power or unlimited without.

 

[Woosh]

if you can wait until August, I will have a new ultra lightweight kit for carbon bikes.

 

[Nealh]

Current lightest geared hub motor is a signwave AKM75sx at 1.44kg for 100mm forks, £81.

Bafang's lightest is 1.7kg but nearly twice the price, £150.

The smallest lightest rear motor is a Keyde 100/s100 with an internal controller, the Cst is for 135mm D/O's and comes in at 2kg, 35nm torque from a small motor max output is 500w, £243.
The max controller is 13/14a and suited for up to a 180lb rider.

All the above are 250 nom rated hubs.

 

[WheezyRider]

Yose are ok but there are better lighter motors and electronic kits available, you only need 10,12 15ah or more for longer 30mile rides. Most of these batteries use poor or mediocre cells and a bespsoke 2p battery using something like HG2 or VTC5/6 cells would out perform them

Nealh, Where is the best place to buy genuine HG2 cells? There are loads of fake ones out there.

HG2 cells are good if you can get genuine ones:

Test of LG 18650 HG2 3000mAh (Brown)

Should be able to get at least 2.5 Ah from each cell at 7.5A draw per cell. But, I still think a nominal HG2 2p "6 Ah" pack is a bit marginal unless you are doing most of the work, are only doing short commutes in warm weather, can top it up when you get to work and it's not windy. It depends on how much you rely on the electric drive, but if you hammer those cells and deep discharge them regularly, after a couple of hundred cycles, they will drop to about 60% or less of rated capacity and your range will decrease accordingly. Having a good reserve prolongs the life of the pack and you should be able to get many more cycles out of it.

Is there any reason why you want it to be particularly light?

 

[Nealh]

If pushing 7.5a per cell in 2p format then 15a is quite a bit of power, a lazy rider will do this probably a throttle rider. I normally ask little more then 1a per cell unless I Iuse PAS 4 or 5 on steeper inclines. The reason people have bigger batteries apart from range is they are lazy and use more current instead of their own power. Ebikes can make riding a bike too easy then they don't become occasional light assistance bikes any more but a higher power source not a kin to riding a moped instead with little effort.


Generally buy from a reputable seller Nkon in Holland or Fogstar wholesale in the uk.
Fake cells tend to have a shiny white insulator the real ones have a textured flat look to them, The wrap print tends not to be very clear looking fuzzy/blurred, genuine cell have sharp clear lettering on them even the warning print on them, The cell has a shallow ring running around the top, fakes have one that is a bit deeper and often 1 or 2mm lower.
There are fake cell comparisons you can look up online to see what to look for in possible cells , one of the scams it to rewrap genuine HE2/HE4 cells in a new wrap to pass off as HG2. Although you get a genuine cheaper cell you also only get the 2500mah. an instant profit with no tooling needed.

Lighter bike means a stealthier bike with better handling and hill ability, a lighter bike doesn't need as much power to fly along.

I have 15/16kg 24v 21 cell bike and it feels much livelier then my 50 cell heavier bike that is probably double the weight, less weight needs less power.

 

[acueductomtb]

If pushing 7.5a per cell in 2p format then 15a is quite a bit of power, a lazy rider will do this probably a throttle rider. I normally ask little more then 1a per cell unless I Iuse PAS 4 or 5 on steeper inclines. The reason people have bigger batteries apart from range is they are lazy and use more current instead of their own power. Ebikes can make riding a bike too easy then they don't become occasional light assistance bikes any more but a higher power source not a kin to riding a moped instead with little effort.


Generally buy from a reputable seller Nkon in Holland or Fogstar wholesale in the uk.
Fake cells tend to have a shiny white insulator the real ones have a textured flat look to them, The wrap print tends not to be very clear looking fuzzy/blurred, genuine cell have sharp clear lettering on them even the warning print on them, The cell has a shallow ring running around the top, fakes have one that is a bit deeper and often 1 or 2mm lower.
There are fake cell comparisons you can look up online to see what to look for in possible cells , one of the scams it to rewrap genuine HE2/HE4 cells in a new wrap to pass off as HG2. Although you get a genuine cheaper cell you also only get the 2500mah. an instant profit with no tooling needed.

Lighter bike means a stealthier bike with better handling and hill ability, a lighter bike doesn't need as much power to fly along.

I have 15/16kg 24v 21 cell bike and it feels much livelier then my 50 cell heavier bike that is probably double the weight, less weight needs less power.

I have a 28 - 622 wheel and even though I think a rear motor is better for a lot of reasons, I want a light front hub. This is for commuting in my old Peugeot and mainly to have a push in the uphills so...

I understand the benefit of Buying Bafang and separate components. But I was researching yesterday https://www.swytchbike.com/ and it doesn't seem that bad. It is just I don't have the time to commit to a full project and I don't want to do mediocre things. I wanted a plug and play solution. Also, Im not in an extra hurry.

My only concern aside from not being available right now is that magnetic pedal sensor. It seems very vulnerable to malfunction due to dirt and other stuff.

Really thank you guys, Im learning a lot with these answers. You answer and I go and research and learn more jajaja

Great Forum!

 

[sjpt]

So you think it is better to get separate components and ask for some service to help me install it?

If you are at all used to bike maintenance then installing it yourself will be easy. The difficult bit is the selection of a set of suitable components that work together; you are getting lots of advice on that here and I'm sure people will help you vet the combination before you make the final buy decision.

 

[Nealh]

Magnetic disc PAS aren't affected by road muck or off road muck, the only issue I have had was with cable tying one on. Now I mechanically fix all in place, my diy kitted out town/commute bike has worked perfectly for six years or so now.
Most solutions in one way or another have been tried and tested in use by many on here.

 

[WheezyRider]

If pushing 7.5a per cell in 2p format then 15a is quite a bit of power, a lazy rider will do this probably a throttle rider. I normally ask little more then 1a per cell unless I Iuse PAS 4 or 5 on steeper inclines. The reason people have bigger batteries apart from range is they are lazy and use more current instead of their own power. Ebikes can make riding a bike too easy then they don't become occasional light assistance bikes any more but a higher power source not a kin to riding a moped instead with little effort.


Generally buy from a reputable seller Nkon in Holland or Fogstar wholesale in the uk.
Fake cells tend to have a shiny white insulator the real ones have a textured flat look to them, The wrap print tends not to be very clear looking fuzzy/blurred, genuine cell have sharp clear lettering on them even the warning print on them, The cell has a shallow ring running around the top, fakes have one that is a bit deeper and often 1 or 2mm lower.
There are fake cell comparisons you can look up online to see what to look for in possible cells , one of the scams it to rewrap genuine HE2/HE4 cells in a new wrap to pass off as HG2. Although you get a genuine cheaper cell you also only get the 2500mah. an instant profit with no tooling needed.

Lighter bike means a stealthier bike with better handling and hill ability, a lighter bike doesn't need as much power to fly along.

I have 15/16kg 24v 21 cell bike and it feels much livelier then my 50 cell heavier bike that is probably double the weight, less weight needs less power.

I think I must fall into the lazy category

No, long ago I used to think nothing of cycling 80 miles in a day, but after getting older and developing leg joint problems and several operations later, I was really glad to be able to get on my modernised Powabyke with it's twist and go. I could hardly turn the pedals at that point some months back. It's improving slowly, but the thought of having to cycle 10 miles back from work into a headwind without assist fills me with dread these days. Plus I like the knowledge that I could go as far as 40 miles if I'm careful on a charge. Also, my commute is further than the OP on this topic and I can't always guarantee I can recharge at work.

In terms of weight, my Powabyke is a steel frame and although I replaced a lot of the heavy steel ironmongery and got rid of the lead acid batteries, it's never going to be a light bike, so carrying an extra kg or so for a 15Ah battery doesn't make a lot of difference. For my hybrid bike, the conversion has added approx 7Kg to the original bike. But most days, I'm carrying a bike lock in a pack on the rear with charger and several heavy books, then I have a back pack on me with two lap tops in it...so I'm not riding light!

I think if I had to lug my bike on and off of trains etc it would be more of an issue. Horses for courses I suppose.

Thanks for the info on the HG2s. I've seen Fogstar on eBay and wondered if they were genuine. Last year I bought a load of HG2s from China for about £2 per cell. I'm quite certain they are fakes. I'm in the process of putting them together into a 10s 6p pack. But TBH if I can get 2.5Ah per cell out of them I'd be happy, it would still work out cheaper than a 15Ah Yose Power pack with Chinese cells.

 

[WheezyRider]

Magnetic disc PAS aren't affected by road muck or off road muck, the only issue I have had was with cable tying one on. Now I mechanically fix all in place, my diy kitted out town/commute bike has worked perfectly for six years or so now.
Most solutions in one way or another have been tried and tested in use by many on here.

Do you put your PAS on the chainring side? Biggest problem I've had with mine, being on the other side where it is exposed is catching it on steps etc, knocking it out of alignment.

 

[Nealh]

Use Fogstar's own web page not ebay, my order turned up within 36hrs, China dud HG2 @£2 a pop will be total counterfeit and not HE2/4 rewraps.

 

[Nealh]

Do you put your PAS on the chainring side? Biggest problem I've had with mine, being on the other side where it is exposed is catching it on steps etc, knocking it out of alignment.

Always behind the chainring.

 

[WheezyRider]

Use Fogstar's own web page not ebay, my order turned up within 36hrs, China dud HG2 @£2 a pop will be total counterfeit and not HE2/4 rewraps.

Cells on Fogstar's own site are more expensive than their shop on eBay. I'll have to contact them and get a quote for larger quantities than 1 cell.

When I get the time, I'll start a write up of my fake HG2 pack

 

[lukemiller]

Hi @WheezyRider

I read this comment with great fascination as it starts to answer many questions about the ebike conversion kit I recently purchased and fitted on my wife's bike. Especially "You will be lucky to get 80% of the quoted rating" and Ah/mile.

I purchased an ebike conversion kit and fitted it to my wife's bike recently, i.e. "Ebike Electric Bike Conversion Kit 36V 250W, 26" Wheel, 36V LNX Motor,36V 11.6A Li-ion (Samsung cells) Battery".

The acceleration and speed when the PAS is running is great and exactly what I expected. The charging of the battery and distance the bike is able to cover on a full charge is not what I expected - although this maybe due to my lack of knowledge and experience.

The battery will only charge to a max of 80%, even though the charger is showing fully charged. Does this sound right and fit in with your point of " You will be lucky to get 80% of the quoted rating". I also read in another forum that some BMS (Battery management systems) only allows the battery to discharge to approx 20% to help the lifetime of the battery. Have you experienced anything similar, and does this mean that only approx 60% of the potential full charge is accessible, e.g. max charge 80% to min charge 20% (80%-20%=60%)?

Should I expect to only have access to approx 60% of the batteries 11.8Ah as well, e.g. approx 7Ah (11.8Ah x 0.6)? The main reason I ask is to help gauge the type of distance we should expect to be able to cover on a full charge.

Apologies for so many questions in a single comment, but I'm really excited to understand better how the kit works and what to expect from it. Hopefully this will help others planning to purchase a kit as well.

Luke

I would look for a kit with a Bafang or MXUS motor, they have a known track record and you can get spare parts. Usually there are kits with the motor and controller/brake levers, pedal assist sensor, etc without a battery and then there are all in kits with the battery included.

Yose Power stuff is generally ok, but I am not overly impressed with their battery packs, although they are probably representative of what is available on the market in terms of mass produced low cost packs. Sometimes they don't have 250W models (UK legal) available on their site. At the moment they only have 20 and 24 inch kits available in the 250W rating.

What is your wheel size?

Are you sure about having a front hub? They have some advantages, like being easier to fit/sort out punctures, but unless you have a good tyre on the front, you can get wheel spinning when starting off and loss of traction in bends. In the wet/on ice this can be a big problem.

Personally, I would not go for less than about 12Ah for the battery and preferably 15Ah. These quoted values are if you completely ran the pack flat at a low discharge rate under ideal conditions. You will be lucky to get 80% of the quoted rating. Plus, you don't want to be discharging the pack to near empty on a regular basis, or it won't last long. And as Nealh says, drawing 15A from a 5 or 6Ah pack needs special cells with a lot of oomph, or they will overheat and fail, or the voltage will sag so much the controller or the BMS will cut the power. I think you will find once you get your e-bike set up, you will want to go further and further, so you may as well get one larger than you think you might need. You'll commute to work one day, then realise you need to go into town, then go somewhere else etc...you don't want to get stranded miles from home without power. Also, you might like to go on longer trips at the weekend.

If you hammer an ebike, expect to consume about 0.5Ah per mile or more. If you go steady and don't have to stop start you can reduce this to about 0.2Ah/mile and less, depending on how hard you pedal.

 

[WheezyRider]

Hi @WheezyRider

I read this comment with great fascination as it starts to answer many questions about the ebike conversion kit I recently purchased and fitted on my wife's bike. Especially "You will be lucky to get 80% of the quoted rating" and Ah/mile.

I purchased an ebike conversion kit and fitted it to my wife's bike recently, i.e. "Ebike Electric Bike Conversion Kit 36V 250W, 26" Wheel, 36V LNX Motor,36V 11.6A Li-ion (Samsung cells) Battery".

The acceleration and speed when the PAS is running is great and exactly what I expected. The charging of the battery and distance the bike is able to cover on a full charge is not what I expected - although this maybe due to my lack of knowledge and experience.

The battery will only charge to a max of 80%, even though the charger is showing fully charged. Does this sound right and fit in with your point of " You will be lucky to get 80% of the quoted rating". I also read in another forum that some BMS (Battery management systems) only allows the battery to discharge to approx 20% to help the lifetime of the battery. Have you experienced anything similar, and does this mean that only approx 60% of the potential full charge is accessible, e.g. max charge 80% to min charge 20% (80%-20%=60%)?

Should I expect to only have access to approx 60% of the batteries 11.8Ah as well, e.g. approx 7Ah (11.8Ah x 0.6)? The main reason I ask is to help gauge the type of distance we should expect to be able to cover on a full charge.

Apologies for so many questions in a single comment, but I'm really excited to understand better how the kit works and what to expect from it. Hopefully this will help others planning to purchase a kit as well.

Luke

Hi Luke, no worries about the questions, it's what the e-bike community is for.

Lots to unpack here. First of all, how do you know you are only charging to 80%? What is the final voltage of the pack?

So you probably have a 10s 4p pack with 2.9Ah cells. This is their nominal rating, if charged right up to 4.2V and discharged maybe as low as 2.5V to get that figure, at a current of maybe only 0.5A. To start with, a lot of chargers do not go to the full 4.2V, as this shortens the life of the cell. Some experts say a cell should not be charged over 4.1V to increase cell life. Yose Power chargers only charge the pack to 41.7V, so a compromise between capacity and pack life. Then, you would never want to discharge as deep as 2.5V, as it might not accept charge again after such a deep discharge. So a BMS will usually kick in at 28V on a 36V pack. On top of that, you have the controller, which is usually set up for 30V low voltage cut out (LVC).

On top of this, discharge characteristics will depend on how fast you drain the cell and the ambient temperature. High current drain will mean you will get much less out of the pack than the nominal rating. Never recharge a pack below 0 deg C, and ideally not below 5 deg C. Discharging at 5 deg C or below will reduce your battery's output.

Anyway, assuming 10 to 20 deg C for discharge at a moderate average rate of about 100 to 150W, I expect to get about 12Ah from my 15Ah pack, so about 80% of stated capacity when charged to 41.7V. If a system is working properly, that is what I would expect.

Do you know what the LVC set up is for your controller? It might be set too high. BMSs are usually set to 2.8V or so, I wouldn't expect them to be much higher than this.

Do you have a Watt meter? Can you measure how many W hr or Ah you are getting out of the pack? What is the pack voltage when the controller shuts down?

 

[acueductomtb]

Magnetic disc PAS aren't affected by road muck or off road muck, the only issue I have had was with cable tying one on. Now I mechanically fix all in place, my diy kitted out town/commute bike has worked perfectly for six years or so now.
Most solutions in one way or another have been tried and tested in use by many on here.

I see.... I found another one check this out, have you heard of this project:

Unlimited eBike conversion kit

Add tons of capability without complexity, perfect for city bikes. Create the perfect electric bicycle with the bike you already know and love.

www.unlimitedev.com

According to what they say in Indiegogo, Ill have to wait but it may be worth it? It seems simple.

Im also, researching at separate controllers and batteries in this site from Canada:

Search results for: 'front g311 kit advanced pas custom build'

ebikes.ca

www.ebikes.ca

Cheers,