8Fun E26M03S

[bill_s]

Hi,
I'm a fairly new member and live on Hayling Island, Hampshire.

I recently bought an 8Fun E26M03S (E26M03S | 26" Electric Aluminium Mountain Bike | 36V Lithium Bottle Battery with Panasonic Cells,21 SP SHIMANO, DISC Brake). This has an 8Fun QSWXK motor (Bafang I think) without hall sensor.

I use it for commuting to Portsmouth via the Hayling Ferry, therefore halving the distance to work compared with driving.

I was very pleased with it for the first 300 miles. In throttle mode, the motor seemed to be derestricted and would keep on helping way past 15mph, although in pedal assist mode it stopped helping at 15mph.

I was always concerned at the lack of weather protection for the controller (mounted under the bottom bracket) and sure enough, within a few days of taking it out in heavy rain, the controller failed. I opened the controller and there was water around one of the IRF1010E MOSFETs and obvious signs of burn-out (see http://www.asta-technology.co.uk/documents/Controller_pcb_with_burnt-out_MOSFET.JPG).
I contacted Anna at 8Fun who was very helpful and sent me a new controller without delay.
Unfortunately the new controller is restricted in both pedal assist and throttle modes and also seems to deliver less power (less able to cope with hills and headwinds). Therefore, I contacted ecrazyman to see if they could send me a replacement derestricted controller. I have sent them the attached picture (see http://www.asta-technology.co.uk/documents/Wires_from_original_controller.JPG) but they need me to tell them the function of each wire. I've added the obvious ones (motor phases, pedelec sensor, battery + & -) but can anyone help with the rest?

Also, can anyone tell me what type of connectors these are (in the picture). Some are damaged and I'd like to replace them.

Thanks in advance, Bill.

 

[Deleted member 4366]

A couple of things to think about: Many of the after-market controllers don't have a connector for your handlebar display/control panel. They normally have connectors for battery, brake switches, pedal sensor (not always) and throttle. Some have additional wires for speed restriction, and if you order a sensored one for a sensor motor (5 thin plus 3 thicker wires) it'll have a connector for the sensors. You can get controllers exactly like yours from Aliexpress.com, but it's not so easy to figure out what they are selling, communication is a big issue and it's not easy to figure out who the bad guys are. However, there's a strong probability that Kudos will be able to help you out at very reasonable cost because I think theirs are the same as yours.
.: Kudos Cycles - e-bikes with style :.
Personally, I don't like the idea of naked controllers - especially located at the BB, where it gets a soaking. If you want to do a bit of wiring, you could move the controller up to the seat-post and enclose it. I have one of these that I can let you have for cost price if you want it:
KU63 Controller Case - BMSBATTERY
Next, unless your motor is sensored, which I don't believe it is, the controller doesn't know how fast you're going, so it can only limit the amount of power, not the speed. If you look at your old controller, I bet it says 14A or 15A max on it, while as your new one says 12A (6A rated). It's possible to do a simple modification that will increase the current back to your 15A that just requires a bit of soldering. Let us know if you want to try this. It's a lot cheaper than buying a new controller.

 

[Blew it]

Also, can anyone tell me what type of connectors these are (in the picture). Some are damaged and I'd like to replace them.

Welcome to the forum Bill, I hope you can revive your machine.

The connectors you need are JST SM 2.5, 2 and 3 pin. Available from Hong Kong.


JST CONNECTORS ON EBAY

Or, A mixed bag of 2,3,4,5 and 6 pin from Canada. Around 23 dollars including P&P

Scroll down to 'ConBag' on this LINK

 

[Deleted member 4366]

The wiring photo didn't come up last tim I tried. Now I can see the wires:
Red, green, black with white connector = throttle
green, black with black connector = brake switches
red, blue with black connector = control panel if you have one. Can you confirm whether you do or not?

 

[bill_s]

Thank you very much for all the info, 'd8veh' & 'Blew it'.

I decided to do what I could with the 8Fun replacement controller. On opening it up and identifying the copper shunt, I noticed that it was notched, whereas the shunt in the original controller was not. I therefore applied some solder over the notches, and it seems that performance is roughly back to where it was (is that the mod you were going to suggest, d8veh?). If there are any more suggestions regarding upping the output, please let me know.

My motor only has the 3 phase wires going into it so I guess that means that it's sensorless. On the other hand, on pedal assist, the power seems to cut at exactly 15mph whether there's a headwind or not which makes me think that there must be a tacho feedback.

Both the old controller and the replacement controller are 'rated 6A, max 13A', according to their labels.

You ask if I have a control panel....Yes it has an on/off button, a button to go up through 3 three power levels (in pedal assist) and a button to switch over to throttle control; it also has a row of LEDs to show battery power level.

Thanks for the offer of a controller case d8veh, but I had an RS instrument case just the right size. I've mounted it in front of the down tube, not as sheltered as the seat post, but at least I didn't have to extend any wires.

Thanks again for all the help. Bill

 

[Deleted member 4366]

Thank you very much for all the info, 'd8veh' & 'Blew it'.

If there are any more suggestions regarding upping the output, please let me know.

You're correct. That's what I was going to suggest, but I've never heard of a shunt notched by the manufacturer.
To answer the above question: Add more solder. When you add solder to the shunt, the controller gives more power. Normally, you start at one end and gradually coat the shunt until you have enough power. The controller and motor can handle upto about 20amps, which gives much better hill-climbing, but less range. To reduce the power, you file notches in the shunt, which had been done to yours. The soldering is best done with a wattmeter so that you can see how much current you're getting. You don't want to go over 20amps because the controller or motor or both can become too hot. If you solder the whole shunt, you could get as high as 25amps.