Swytch mark 2 battery rebuild

[Cisco-man]

The picture is of what I believe a Gen 2 controller looks like, but I’ve not had my hands on one personally!

 

[StuartsProjects]

The controller in the Swytch pack uses YLS connectors for the display, PAS etc, these are smaller than the normal Julet type. Then a XT30 for the battery and 3 pin MR30 for the motor phases. These connectors then feed into the connector on the back of the pack.

The matching connector on the handlebars then converts these connections into the more normal Julet and motor connectors found on KT controllers etc. The exception is the brake sensors which are 4 pin blue Julet, KT setups tend to use 3 pin orange julet or two pin red Julet.

Getting Julet cables for extensions is easy enough, dont know where you get the YLS type.

 

[Cisco-man]

This is where Rig the Gig’s technical guy will be needed - to basically engineer the removal of the gen 2 pack-to-handlebar connector. Should be fully achievable with additional wire, soldering and shrinksleeve.

 

[rig the jig]

The battery pack will be self-contained with charger and bms integral to the pack. You only need to take the two wire output and join them to the controller (red and black). The battery pack’s only function is to provide your power. The pedal assist sensor is a three pin plug into the controller, which is 0v and 5v from the controller to the pas, and a signal wire back from the pas into the controller. The pas is just a hall-effect device giving an alternating signal as the magnets pass the sensor. Not sure what you mean by “accelerator handlebar switch”. Do you mean the display, or do you have a throttle of some sort? Either way, they would connect to the controller. I think the controller will have mainly the right connectors, but photograph the connectors when you remove the controller and we should be able to advise more then.

\the accelerator is just a thumb throttle device.

 

[rig the jig]

I’ve been pondering this for a while as by brother has a gen 2 Swytch setup and both his battery packs are slowly failing.
There’s major sense ditching the gen 2 battery for a more generic one, but it potentially leaves you with an almost empty bag hanging on the handlebars that still houses the controller and display. A lot of battery panniers appear to have a controller box, so the controller could be reused, but you still would need a new display for your handlebars. It would be a nice thing to have a migration path for Swytch gen 2 owners to follow.

I am willing to be the guinea pig for this project, if you could recommend the battery, controller, and other bits I need, I am willing to have a go at completing the job. I want to get a 10 amp Hr battery or better, so the ball is in your court so to speak.

 

[matthewslack]

Search 'swytch connector' on this forum and scroll down the results list to several recent threads that probably cover everything that is needed.

 

[StuartsProjects]

Would be an idea to post a picture of the bike ?

 

[saneagle]

I am willing to be the guinea pig for this project, if you could recommend the battery, controller, and other bits I need, I am willing to have a go at completing the job. I want to get a 10 amp Hr battery or better, so the ball is in your court so to speak.

The first step is to take the battery and controller out of the bag, put it on the table, measure them and photograph them. If they're in a plastic box, remove the screws and photograph what's inside.

After that, measure the space inside your bag.

In the 5 years that people have been buying and fitting this kit, I'm surprised that nobody on this forum has done that. It takes about 5 minutes and gives you all the answers. Everybody is waiting for somebody else to do it. None of this stuff is difficult, but we can't advise you if you don't show what you've got.

 

[Cisco-man]

… he has the connectors - as long as he has a few inches

Search 'swytch connector' on this forum and scroll down the results list to several recent threads that probably cover everything that is needed.

The post I think you refer to is the one I did for the Gen 3 Swytch kit, where the battery clips off and the controller stays on the bike. This thread is for the Gen 2, where the controller, display, and battery are all in a bag that hangs on the handlebars.

 

[Cisco-man]

The controller in the Swytch pack uses YLS connectors for the display, PAS etc, these are smaller than the normal Julet type. Then a XT30 for the battery and 3 pin MR30 for the motor phases. These connectors then feed into the connector on the back of the pack.

The matching connector on the handlebars then converts these connections into the more normal Julet and motor connectors found on KT controllers etc. The exception is the brake sensors which are 4 pin blue Julet, KT setups tend to use 3 pin orange julet or two pin red Julet.

Getting Julet cables for extensions is easy enough, dont know where you get the YLS type.

Great info - thanks.
He has the connectors needed already - as long as there is a few inches of cable attached to them!

 

[StuartsProjects]

He has the connectors needed already - as long as there is a few inches of cable attached to them!

But you still need to use the multiway connector block in the bag mated with the matching multiway handlebar connector to connect the stuff like the motor, PAS, brakes, throttle ...............

 

[Cisco-man]

But you still need to use the multiway connector block in the bag mated with the matching multiway handlebar connector to connect the stuff like the motor, PAS, brakes, throttle ...............

Not fully convinced of that - although I’ve not got my hands on a gen 2 controller yet. My reasoning is that for each cable connection to the controller (PAS, display, and motor) there will surely be a mating connector that cables up to the big connector. By cutting as close to the big connector as possible there should be enough of a tail on the connector to make up an adapter cable. There aren’t many wires in each connection - PAS has 3, display has 5, motor has 9. There’s even youtube vids on how to extend the display cable - so that’s well understood. Not for the faint-hearted I accept, but if it’s approached carefully and as Saneagle says, documented properly, it won’t be a hard job. Maybe a new controller is a good way forward, but at the moment he has a fully working bike and just needs a new battery. A new controller leads you down other paths and compatabilites that I don’t think are necessary. Phew! A long post - sorry!

 

[rig the jig]

Battery pack is 190 WX125 H attached are photos of battery and cables. I have no problem converting the bike into a rear carrier type set up, and extending the cables to the handlebars if this is the easiest route to go.

 

[Cisco-man]

Marvelous! First thing - get the battery into a safe situation - unplugged and out of the way. Get some masking tape and add an ID flag to each cable coming out of the controller. It’s obvious which one is the display. Add flags to all the connector/cables coming into the big connector housing, from all the devices on the bike (PAS, throttle, motor, brakes) and try to trace them through the big connector and identify the associated controller connectors.

 

[Cisco-man]

The method I suggest is based on only doing one job at a time, and fully testing before moving on.
First job would be to work out how long a cable you need for the display to reach from the new controller location to the handlebars and doing extending the display first (watch the youtube for that) - then fully test the bike.
Second job would be to extend the PAS in the same way - probably using a julet extension cable - again testing afterwards. Ditto for the throttle, and leaving the motor connection to the last.

 

[saneagle]

Battery pack is 190 WX125 H attached are photos of battery and cables. I have no problem converting the bike into a rear carrier type set up, and extending the cables to the handlebars if this is the easiest route to go.

That's excellent, thanks.

You have room for a downtube battery, so that's what I'd get for best handling and most convenience.

You have a few choices with the controller. First would be to chuck it and get a KT one, which gives better pedal assistance power algorithms. You can get one as a complete kit with a throttle, pedal sensor and speed sensor for about £80. Stick it in an under saddle toolbag and get rid of the monstrosity on the front of your bike. Your bike will then be like a new one, and you'll like it much better. It looks like your motor is sensorless (only 3 wires), so you need a square-wave KT controller. There's a slight possibility that the controller might not work very well with your motor, so a bit of risk to think about. Sensorless motors can be dodgy.

Second choice is to leave the bag and controller in place, and run the two wires from the battery up to it. One connector and you're done.

Third choice is to buy another small cell-pack and put it in the bag. That's good if you want to remove the bag when the bike is at work or otherwise parked up. You might be able to get a 10S3P battery in there, but check the sizes first. such a cell-pack should cost around £120 and give you double the range you had before. If you can't fit it in the bag, you can buy bigger bands that you'd need to adjust for the cables and control panel.

Fourth choice is the same as the first, but use a Brainpower controller with LCD. They cost about £40 and free you from restrictions that you have with your present controller, plus you get an LCD with speed display, etc. You'd need a wheel speed sensor to go with it that you can nick from any old cycle computer or by a cheapp cyclecomputer from Ebay and cut it off. Make sure the controller is a dual mode one (sensor and sensorless). Those controllers don't seem to be so fussy about the motor.

 

[Cisco-man]

Saneagle has lot more experience than I do. Take his advice in preference to mine!

 

[StuartsProjects]

The cable layout in your Swytch bag looks to be the same as mine, 3 pin motor cable etc, see post #22 .

I removed the Swytch kit from my first Brompton, so thats now human effort only.

The Swytch motor wheel is currently running just fine on my other Brompton with a normal KT Sine Wave controller and LCD4 display.

 

[saneagle]

The Swytch motor wheel is currently running just fine on my other Brompton with a normal KT Sine Wave controller and LCD4 display.

If your uses a sinewave controller, it must be sensorless. The picture in post #33 seems to show a sensorless motor, but it's not difinitive.

 

[rig the jig]

If your uses a sinewave controller, it must be sensorless. The picture in post #33 seems to show a sensorless motor, but it's not difinitive.

The cable from the controller to the motor has nine pins so it must be sensorless.