Any tips for neatly wiring up an ignition?

[fireaza]

Hey guys! I recently picked up a new ebike, however it came with a half-throttle and no ignition key. I'm not a fan of the half-throttle (my fingers hit the gear shifters, so I have to pinch it at an awkward angle) and I'd really like there to be an ignition key. I found this on Aliexpress that should kill two birds with one stone:

https://www.aliexpress.com/item/1005004837454183.html

Now, the problem is, my bike uses Juliet connectors, not SM connectors. That's simple enough for the throttle, I just need to remove the SM cable and solder a 3 pin Juliet cable in it's place.

It's how to wire up the ignition key neatly that I'm not sure about. I'd really rather something neater (and more waterproof!) then simply splicing the key wire into the display's power. Does anyone have any good recommendations?

The only thing I can think of is replacing the ignition cable with a REALLY long one, running that into the wiring box, splicing that into a short Juliet extension cable and putting this cable between the display cable coming from the controller and the display's cable. I haven't had the time to open up my ebike and take a look at how it's wired up, but I'm assuming that since the display cable is so short, that there's a male-to-female extension cable connected to the controller, since I doubt the hard-wired cable is THAT long!

I've noticed that my display's manual (https://utfs.io/f/464b3da1-879a-4703-9e4d-a146f58cbcf4-2e9ra7.pdf) says pin 2 of the connector is "lock", is this somehow related to ignition keys?

 

[offGridDownUnder]

I do hope you don't actually want your electric vehicle to ignite.

 

[fireaza]

I do hope you don't actually want your electric vehicle to ignite.

Well then, how about the "make ebike go vroom-vroom key hole"?

 

[chuyskywalker]

On the Phaserunner controllers, the "K" pin can be connected/disconnected from the "B" pin to lock/unlock the bike with a key switch. However, on the PR, the B is battery voltage, not a display voltage (which is usually a lot less, like 52v vs 5v).

Maybe this controller works the same way, but I'm personally not sure. Just giving a, seemingly, comparable bit of info.

In many other controllers that have key switches, this is usually also the same case, because often times the "key switch" also contains a volt meter. So the idea is that the battery power is running up to the handle bar and is stopped by the open key switch. When the key is turned, closing the circuit, the key output is then connected to the voltmeter and splits back to the controller. (The voltmeter also shares a ground with the throttle). This is why you have, typically, 5 wires: constant battery + voltages, battery + voltage return (k), then ground, 5v, throttle signal. On the one you linked, it's pretty much all the same, just no voltmeter up in the mix.

 

[fireaza]

It was surprisingly hard to find a full-length throttle, WITH a key, but WITHOUT a voltage display! No idea why the oppisite is so popular, if you want to check your battery level, why not just look at the main display? Showing the amount of throttle being applied would be a good use for a display on the throttle, but they don't exist as far as I can see.

I think what you mentioned about disconnecting pins might be at play here too. I mean, what else could a pin marked as "lock" mean? It sounds like I could test it by disconnecting the display plug, running some wires to bridge the connections, and seeing what happens when the "lock" pin is disconnected.

 

[E-HP]

It was surprisingly hard to find a full-length throttle, WITH a key, but WITHOUT a voltage display! No idea why the oppisite is so popular, if you want to check your battery level, why not just look at the main display? Showing the amount of throttle being applied would be a good use for a display on the throttle, but they don't exist as far as I can see.

I think what you mentioned about disconnecting pins might be at play here too. I mean, what else could a pin marked as "lock" mean? It sounds like I could test it by disconnecting the display plug, running some wires to bridge the connections, and seeing what happens when the "lock" pin is disconnected.

from my faq, Chinglish to English translation::

• Electric Key Lock/Key Switch/Electric Door Lock/Ignition/Power Lock : Controller on/off; usually applying battery level voltage to the signal wire turns on the controller (frequently a thin orange conductor).

Your display buttons electronically switch the battery level voltage from pin 1 to output on pin 2 to turn on the controller. If you want to add an additional key switch, you need to cut the blue wire and insert the switch in series. If you want to bypass the display on/off, and only use the key switch, you'd need battery level voltage on one leg of the switch, and the lock input to the controller on the other leg.

PS. the reason many throttles have the voltage readout is because its the only readout most people need when opting to run without a display.

 

[fireaza]

Good info! You mentioned that the display turns on by sending battery level voltage from pin 1 to pin 2. Could I install the key simply by bridging these two pins with the lock? If I'm not misunderstanding things, this would prevent the display from being turned on when the key is locked, and automatically power-on the display when the lock is unlocked?

 

[glennb]

The key switches are shite. They rust out in no time. Better to use a high quality weatherproof switch. You can locate it anywhere on the bike, really no need for it to be on the handlebars.

 

[fill]

Fwiw I have a mind to epoxy a hall sensor inside some accessible steel tube on my bike bike Seat post probably or add some steel with the sensor if it too is non ferrous.. then on and off is simply sticking a magnet in place- High security as only I (and all you) know about the magnets significance and where the magic on spot is.. - no lost key concerns any magnet will work..

edit-- if no switch circuit to use just branch off another brake sensor lead, they even sell julet Y cables for similar application with gear shifting sensors..

Further edit.. - vibrations and shocks during a ride, could dislodge a magnets position stuck on a vertical tube? a velcro strap or silicone/rubber band may be required for rougher terrain? - yeah perhaps not 100% thought through yet.. a test tide with a few neodymium magnets stuck to any steel surfaces may be in order to see if they shift..

And further edit.. 3d printed 'mock' cable clip to circle a tube and hold a magnet and enough grip to resist shock movement but can be slid/twisted out of place. - i will shut up n get my coat now..

 

[Diggs]

a test tide with a few neodymium magnets stuck to any steel surfaces may be in order to see if they shift..

That's what hard drive magnets are made from and no, they won't shift at all. In fact they are used to hold the whole battery on to the bicycle with Luna Wolf Packs as shown in this post. The mount screws to the frame and the pack just snaps in and out on the magnets. I always thought this was suspect but in the 1,000s of miles it was never an issue -

EM3ev vs Luna Batteries and Kits

Quality I see everyday, this Liquid Wolf. Rugged by design, constructed like 'mil-spec' aircraft componentry.

endless-sphere.com

 

[fill]

That's what hard drive magnets are made from and no, they won't shift at all. In fact they are used to hold the whole battery on to the bicycle with Luna Wolf Packs as shown in this post. The mount screws to the frame and the pack just snaps in and out on the magnets. I always thought this was suspect but in the 1,000s of miles it was never an issue -

EM3ev vs Luna Batteries and Kits

Quality I see everyday, this Liquid Wolf. Rugged by design, constructed like 'mil-spec' aircraft componentry.

endless-sphere.com

My rear end may beg to question you, some of the pot holes i have missed in my forward view have sure given me a real shock and shifted things not meant to be shifted..

And perhaps the curved surface of a tube and flat face of a magnet resulting in only a small proportion of direct contact may be influential?? (unqualified armchair engineer with a browser and unused search facility sat here..)

My bike has a couple of flat steel (i think) surfaces i could exploit so if full contact is required for magnetic stability under duress that can be achieved, shame tho as i am kind of attached to the in tube concept as a sensor and wires can be more easily spotted behind the small flat steel surfaces found on bikes, which ruins the mystery security aspect..

So I hope your right and im wrong, and as i have some hobby magnets and the cheapo tube rack on my bike front is bound to be steel.. (see icon pic) testing will progress...

 

[E-HP]

Good info! You mentioned that the display turns on by sending battery level voltage from pin 1 to pin 2. Could I install the key simply by bridging these two pins with the lock? If I'm not misunderstanding things, this would prevent the display from being turned on when the key is locked, and automatically power-on the display when the lock is unlocked?

When the display is powered off, you need to press the power button to turn it on, so I don’t think it will work as you described. I just use a remote switch instead of a key lock to disable my bike.

 

[fireaza]

Damn, so my best bet is the use the key to disconnect the pin 2 ("lock")? Is there a neater was to do this that's not literally cutting the wire and putting the key between the cut? Could I, say, get a Y splitter cable, disable pin 2 on the side that goes directly from the controller, and put the key on pin 2 connected to the lock on the other branch? That's doesn't sound quite right to me, but it seems like something similar might work.

 

[fill]

Damn, so my best bet is the use the key to disconnect the pin 2 ("lock")? Is there a neater was to do this that's not literally cutting the wire and putting the key between the cut? Could I, say, get a Y splitter cable, disable pin 2 on the side that goes directly from the controller, and put the key on pin 2 connected to the lock on the other branch? That's doesn't sound quite right to me, but it seems like something similar might work.

Sure a Y splitter cable in the brake sensor line will give you the ability to switch the bike on/off again with a keylock containing a switch with Closed when locked terminals. You can hack the splitter cable for wire access or buy a bare tailed 2 wire/3wire julet plug lead form ebay.. If your bike uses the julet plugs/sockets?

Your controller label may have a confirming indication like " BRAKE:Low", which would indicate the brake sensor wire would require grounding to activate the motor cut off. in which case wire your keylock such that when locked the gnd and sensor wires are connected, and disconnected when unlocked.. That way regardless if someone finds the battery on switch or turns on your bike the motor wont run unless the key unlocks it.. or they pull the wire to the lock.. (heatshrink..)

 

[TommyCat]

Hi fireaza,

If you are sure your controller doesn’t support an ignition or key lock circuit.

I do know that putting the key switch in series with the power wire going to the display works.
This requires a 2 start up sequence, first turn the key on then press and hold the display on button for system power up.

If this is acceptable.
You can read about it in this thread, whist ignoring the references to the throttle‘s digital voltage display…

Wiring a Twist throttle -volt meter-key combo - Electricbike.com Ebike Forum


I have read some where that you shouldn’t switch the “lock“ line or jumper between the two, but I can’t tell you why.



Regards,
T.C.

 

[fireaza]

Sure a Y splitter cable in the brake sensor line will give you the ability to switch the bike on/off again with a keylock containing a switch with Closed when locked terminals. You can hack the splitter cable for wire access or buy a bare tailed 2 wire/3wire julet plug lead form ebay.. If your bike uses the julet plugs/sockets?

Your controller label may have a confirming indication like " BRAKE:Low", which would indicate the brake sensor wire would require grounding to activate the motor cut off. in which case wire your keylock such that when locked the gnd and sensor wires are connected, and disconnected when unlocked.. That way regardless if someone finds the battery on switch or turns on your bike the motor wont run unless the key unlocks it.. or they pull the wire to the lock.. (heatshrink..)

Hmmmm, I was hoping for a straight "bike no turn on without key" setup, using the brake line to disable the motor isn't quite what I'm after... There's no way to avoid having to cut the power wire to the display and bridging the cut with the key?

Hi fireaza,

If you are sure your controller doesn’t support an ignition or key lock circuit.

I do know that putting the key switch in series with the power wire going to the display works.
This requires a 2 start up sequence, first turn the key on then press and hold the display on button for system power up.

If this is acceptable.
You can read about it in this thread, whist ignoring the references to the throttle‘s digital voltage display…

Wiring a Twist throttle -volt meter-key combo - Electricbike.com Ebike Forum


I have read some where that you shouldn’t switch the “lock“ line or jumper between the two, but I can’t tell you why.



Regards,
T.C.

I haven't had the time to check my controller, but seeing if it has a dedicated lock circuit would be the first thing I'll do!

Yeah, it's looking like spicing the power line to the display is my only option here. I was hoping for a cleaner setup that wouldn't require trying to waterproof any splices.

 

[E-HP]

Hmmmm, I was hoping for a straight "bike no turn on without key" setup, using the brake line to disable the motor isn't quite what I'm after... There's no way to avoid having to cut the power wire to the display and bridging the cut with the key?


I haven't had the time to check my controller, but seeing if it has a dedicated lock circuit would be the first thing I'll do!

Yeah, it's looking like spicing the power line to the display is my only option here. I was hoping for a cleaner setup that wouldn't require trying to waterproof any splices.

Marine grade shrink wrap tubing has adhesive in it to make the connection water tight,

 

[TommyCat]

Yeah, it's looking like spicing the power line to the display is my only option here. I was hoping for a cleaner setup that wouldn't require trying to waterproof any splices.

How about the tie-in inside the display? I’ve seen mods/repairs that shows access to the interior is possible. It would be more difficult, but a direction you may want to pursue.

FWIW, I would’t trust anything in E-bike components to be truly waterproof, unless you know for sure differently and is guaranteed to be.

 

[docw009]

Good info! You mentioned that the display turns on by sending battery level voltage from pin 1 to pin 2. Could I install the key simply by bridging these two pins with the lock? If I'm not misunderstanding things, this would prevent the display from being turned on when the key is locked, and automatically power-on the display when the lock is unlocked?

First make sure the keyswitch wires are independent of any of the throttle wires. You can put your keyswitch on either the pin 1 display power wire or the pin 2 controller start wire. If you put it on the latter circuit, you can power up the display w/o needing a key. It tells you the display works, but then you go duh, I forgot to powerup the bike when it doesn't move, Otherwise, a switch on the power line will immediate;ly tell you you forgot to power up the bike.

In my DIY ebike world, there are so many scenarios where I power up my ebikes and they don't move that I just prefer to not have the extra wrinkle of a power switch, I have purchased them and realizeed that I don't want a key that can be lost,

I've tapped into the display cables to get to the battery/ground lines so I can add USB modules or stand alone voltage displays, If you have water proof connectors, you can slip heat shrink tubing over the connector, and use liquid rubber and electrical tape as needed to finish it off..

 

[fill]

Hmmmm, I was hoping for a straight "bike no turn on without key" setup, using the brake line to disable the motor isn't quite what I'm after... There's no way to avoid having to cut the power wire to the display and bridging the cut with the key?

As long as your system has an auto shut off after 2-5 minutes its effectively the same, The obvious flaw is simply pulling a plug connection to the lock will bypass it like any other brake sensor .. But just use heatshrink to cover and seal against pulling with any vulnerable connections.

Even with a switch/lock making /breaking the blue controller feed with battery +ve you will still need to switch both the battery and display on to operate the bike. - using the brake sensor 'crack' just means the display will turn on allowing pas selection etc in advance of 'turning on' with the key, which could be considered a positive feature..

 

[TommyCat]

When the display is powered off, you need to press the power button to turn it on, so I don’t think it will work as you described.

You can put your keyswitch on either the pin 1 display power wire or the pin 2 controller start wire. If you put it on the latter circuit, you can power up the display w/o needing a key. It tells you the display works, but then you go duh, I forgot to powerup the bike when it doesn't move, Otherwise, a switch on the power line will immediate;ly tell you you forgot to power up the bike.

Do I understand correctly, that if you break the incoming power wire to the display. Using the key switch to provide that power to BOTH pins 1 and 2 simultaneously. One would STILL have to press the power on display button to get it to light up...?

 

[TommyCat]

Bump.

 

[fill]

Bump.

Yes, probably to turn on the display. Cant say for sure tho as i have only used the 'short trick' to run a bike with throttle only and headless (no display).

My thinking is that if not 'hacked' the display will be receiving battery voltage on the pin1(red wire) and when turned on it would make that battery voltage connect to pin 2 (blue wire). The inverse connecting red and blue will not necessarily turn on the display unit. - it might, but its not by design if it does. its not a simple latching switch circuit but a logic circuit triggered by a momentary switch, so Chances are you still need to satisfy the display start up conditions by pressing the on button.

So .. Yes. Probably.

testing should be simple enough if you can expose the red and blue wires, create a short and see if the display spontaneously turns on .. If so Im wrong, and will be happy to be proven so. live n learn etc...

 

[E-HP]

Do I understand correctly, that if you break the incoming power wire to the display. Using the key switch to provide that power to BOTH pins 1 and 2 simultaneously. One would STILL have to press the power on display button to get it to light up...?

I agree. I can't speak to all displays, but for the KT LCD3 and the UCK1 (came with a Sabvoton controller) displays, that is/was the case. My guess is the extra chip needed to build that functionality into the display would cut into profits.

 

[TommyCat]

Thank you for the replies, much appreciated.