Dawes ARC ii 2020 rebuild

[Welly_59]

I picked up a Dawes arc ii 2020 via my employers cycle to work scheme, and as is usual for me, I'm looking to mod it already.

I chose this bike as I wanted something I could fold up on the train but also to assist up the hill on the commute home.

What I want out of this bike is:
Throttle
LCD display
Bigger battery

The bike is limited to 25kph as expected, but what I have noticed is that there is no taper on the assistance. I can ghost pedal on the flat and on the highest assistance level I still reach 25kph. I was expecting less assistance as the speed progressed but that does not seem to be the case.

First up will be swapping the standard controller and led display for this:

24V/36V 250W 6Mosfets 15A Brushless DC Sine Wave Controller - PSWPOWER.com

www.pswpower.com

That will cover my itch for throttle and display. Once that is done I will start on getting a higher capacity battery.

The current battery fits in the frame, 10s3p, but using pretty rubbish batteries with 2200mah capacity. Totalling 6.6ah

I want to get it rebuilt with 3400mah batteries, giving a capacity more in the range of 10.2ah

My next post on here will be documenting the existing cabling on the bike, and the arrival of the new parts when they arrive

 

[Woosh]

before you buy the parts, you should post pictures of the controller's connectors and motor cable connector.
As for rebuilding the battery, I don't think it's possible.
You can of course replace it with a higher capacity one.

 

[Welly_59]

That's exactly the same battery pack as on my bike.

I have seen those cases, and filled batteries in Alibaba etc, but I'm not sure I trust ratings and capacity on a Chinese battery. I would rather pay for someone in the UK to swap the cells with higher capacity ones.

I have taken a picture of the controller, but I'm on mobile right now so cannot post it. It definitely does not have a throttle cable.

The motor wiring is 3 phase plus hall sensor. Motor in question is a mxus xf08

 

[Woosh]

you can't rebuild into the same case, it's usually gunked up with silicon glue.

 

[Welly_59]

Hmm I'll have to take a look, I have taken the battery case apart, and doesn't seem too difficult for a pro. Quite a bit of space. The cell pack itself is not glued to the case.

For now though I want to focus on the controller upgrade. The battery can wait until this is finished

 

[Nealh]

Ebikebatteries.co.uk in N.London, Jimmy is the man.
For a descreet lcd then a kt lcd4 is probably the answer, go to topbikekit for many options to choose from.

 

[Welly_59]

Only issue with lcd4 is that I don't think it has all the P/C options available?

Vfr400 is going to test in the next day or so and let me know.


That topbikekit site, is it trustworthy? The translation is a mess

 

[Welly_59]

What's the recommended method of posting pictures on this forum? I have pictures of controller and wiring to post

 

[Welly_59]

Controller

 

[Welly_59]

Wiring. As you can see, no throttle cable.

I can see 3 phase, power, display connector, 2 X brake connectors, Pas sensor, and hall sensor

 

[Woosh]

that's pretty much standard cabling. I think you are in luck!

 

[vfr400]

The sine wave controller you mentioned should work pretty well. You'l have to change the connector on the hall wire, or better still, cut the connectors off and solder the wires.

I don't know which 3400 cells you're looking at, but be aware of the current they can supply. I made a 20 cell battery with 20 amp 3000 mAh LG cells in it. It should have been 6Ah, but at only 10 amps ( 5A per cell), its capacity reduced to 5Ah, when tested on a battery tester. Whatever the cells are supposed to be rated at (currentwise) divide it by two. that means a 30 cell battery for your 15 amp controller needs to have cells rated at 10 amps continuous each as a minimum.

Jimmy will be able to help you with an appropriate choice of cells, so discuss it with him.

 

[Welly_59]

Any idea where i could find the correct connector for the hall sensor to either match the new controller or to match the existing connector coming from the motor?

I'd rather be able to unplug the controller in the future without having to unsolder the hall sensor cabling

 

[vfr400]

You have the 9 pin connector on the end of the motor wire. You don't need connectors at each end.

 

[Welly_59]

Right, didn't know there would be a connector closer to the motor as well.

Anyway, I've ordered the it kit via pswpower. Paid for tnt shipping and they say it will be 3-5 working days.

Now it's just a waiting game

 

[vfr400]

Right, didn't know there would be a connector closer to the motor as well.

Anyway, I've ordered the it kit via pswpower. Paid for tnt shipping and they say it will be 3-5 working days.

Now it's just a waiting game

Not all bikes have the 9 pin connector near the motor. Have a look to make sure. It'll be about 9 inches from the motor if you have one.

 

[Welly_59]

So my new controller and accessories has arrived, but I'm struggling to work out the wiring. There seems to be a bunch of extra connectors I did not expect.

Could someone help me identify what wire is what please?

 

[vfr400]

Starting at the white one at the top.
Speed sensor
PAS
Throttle
Brake
Brake
LCD
Hall sensors including motor speed sensor
Light switch
Horn switch
Horn (battery voltage) light (battery voltage)and ground
Blue pair cruise - leave disconnected
Grey pair EABs - leave disconnected
White pair speed limit - leave disconnected and set speed in LCD

 

[Welly_59]

Thank you!

 

[Welly_59]

I'm home today so thought I'd start on the bike.

Fitted the display and throttle on the left bar and then moved onto the controller.

And this is where I have hit my first issue. The replacement controller has female plugs whereas the original had male, and vice versa.

What my best option here? I was thinking of snipping the correct plug/socket off the old controller and cutting off the wrong one off the new controller and soldering it back inline.

Any other better options for me?