Gtech battery swap ?

[antfisher116]

Hello everybody .
I have a Gtech bicycle . With a dead battery ( very common apparently) Would it be possible to switch the battery to a more ready available battery like this as a straight swap . Or is there a reason why not I'm not interested in adding a throttle or boosting the speed just want to use the bike before it gets scrapped . Thanks

 

[Chalo]

If the battery has only two fat(ish) wires coming out of it, then all you need to know is what voltage it is, how much current your controller demands, and how much capacity you want. You should get one that comes with its own mounting rail, so there won't be a compatibility issue with the terminals on the battery pack.

That battery format is called "kettle" on the aftermarket.

Example:

36V 14Ah 10S4P e-bike battery Li-Ion Mountain electric bike kettle mould DIY | eBay

Battery capacity: 14Ah. Electric bicycles, aeroplane models, power tools, battery DIY. high quality! The battery has an integrated BMS protection board.

www.ebay.com

 

[antfisher116]

The Gtech battery and holder has 4 pins . The image of battery in my post has 4 pins as well . Does that mean that the controller / sensor has feedback to the battery ?

 

[Chalo]

Those are redundant power terminals that may or may not all be hooked up, but they're for power and not signal.

 

[fechter]

You could use an ohmmeter to measure between the terminals to see if they are actually in parallel (or take the socket apart and look at the wiring behind it).

 

[amberwolf]

Just keep in mind that it is possible (probable) that your motor controller is inside the battery moutning bracket that's fixed to the bike. So whatever replacmeent battery you use may have to fit that bracket to make hte swap "easy".

 

[antfisher116]

Just keep in mind that it is possible (probable) that your motor controller is inside the battery moutning bracket that's fixed to the bike. So whatever replacmeent battery you use may have to fit that bracket to make hte swap "easy".

Thanks amber wolf that was one of my concerns also . So if I strip down the plug and there is no PCB and just cables going into the frame then it is likely to just be a power source ?

 

[antfisher116]

You could use an ohmmeter to measure between the terminals to see if they are actually in parallel (or take the socket apart and look at the wiring behind it).

Ok that makes sense . Should I do this with the motor unplugged?

 

[amberwolf]

Thanks amber wolf that was one of my concerns also . So if I strip down the plug and there is no PCB and just cables going into the frame then it is likely to just be a power source ?

Where does your motor cable run to? That's usually the controller.

 

[antfisher116]

I found this image of an opened up battery holder

Red and black are obviously power , what would the green and yellow wires be for ?

 

[amberwolf]

what would the green and yellow wires be for ?

Where do they connect on the board?

 

[antfisher116]

Well after some deliberation and some information I found on facebook . The battery can be replaced and be plugged straight into the 2 outer terminals ( + - ) on the Gtech battery holder . The pedal assist works but you loose the option to run on lower power assist , this is what the 2 inner terminals are on the speed controller .
All i needed to complete the conversion was a motor extension cable , 6 pin extension cable and a new battery and holder , I stripped down the speed controller then put inside the saddlebag and ran the cables to the saddlebag .
It all looks pretty neat and now i have it working I need to sort out the cycle parts . I havent ruled out adding a new speed controller, throttle and display , but this will need also a new PAS system as I cannot find any information on how the gtech / bafang bottom bracket wiring works , so if anybody has any information about the bafang bottom bracket wiring diagram it would be appreciated .
Thank you again for everybodys comments and advice

 

[dazzer1970]

Well after some deliberation and some information I found on facebook . The battery can be replaced and be plugged straight into the 2 outer terminals ( + - ) on the Gtech battery holder . The pedal assist works but you loose the option to run on lower power assist , this is what the 2 inner terminals are on the speed controller .
All i needed to complete the conversion was a motor extension cable , 6 pin extension cable and a new battery and holder , I stripped down the speed controller then put inside the saddlebag and ran the cables to the saddlebag .
It all looks pretty neat and now i have it working I need to sort out the cycle parts . I havent ruled out adding a new speed controller, throttle and display , but this will need also a new PAS system as I cannot find any information on how the gtech / bafang bottom bracket wiring works , so if anybody has any information about the bafang bottom bracket wiring diagram it would be appreciated .
Thank you again for everybodys comments and advice


View attachment 375323

hi i have a gtech with a dead battery i wonder if you can help as im thinking of doing similar to you where did you purchase the motor extension cable and were did you the speed controller a how to on this would be awsum if at all possible many thanks