Kill switch ideas for twist throttle?

Happy owner of a SurRon but this applies to twist throttles in general.
On a couple of occasions I have stood aside from the bike and gently used the throttle to help push the bike up/over trail objects, such as a vertical cut or big log.
If the rear tire suddenly catches good traction on the object the bike jets forward and naturally, with me holding the grips, the throttle instantly gets twisted and there goes the bike end-over or off on a ghost ride.
I can install a kill switch easily...question is where to put it for these situations...
I'm out of ideas.

Since with the bike trying to run away from you it'd be tough to reach for and grab something, the best thing you can make is an easily-pulled-out connector with just a loop of wire from one to the other, that connects the "ignition / keyswitch" wire from the controller to the keyswitch or battery, etc.

You can do this for any low-current signal wire that has to be present for the bike to run (including the 5v to the throttle itself, if you prefer a low-voltage signal instead of battery-voltage).

Then you put a lanyard on that connector, and connect it to yourself (wrist, belt, whatever) whenever operating the bike in a situation you feel it could be needed.

If the connector is too hard to pull out, it won't do the job easily, so one option is simple Anderson PP45s with the low-retention-force contacts; this will pull out really easily with a little tug, as long as it is inline with the connector direction. If it's too much of an angle toward perpendicular, it eitehr won't pull out or it will damage things as it does so. If you make it as a pigtail that "hangs" out of the bike wherever is convenient, rather than a panel-mounted plug, it will greatly increase the range of positions you can be in and still have it pull out cleanly. The PP45s are non-gendered so you just need four PP45 shells and four low-retently contacts.

You could instead build in a magnetically operated switch (reed, hall, etc) somewhere, and use the lanyard to pull a magnet away from that. No connector problmes because there isn't one. The switch would still break a low-current circuit (throttle 5v is a good choice) just like the other one.


FWIW, this is also a potential "security" device, in that without the plug in place, the bike is disabled and wont' operate. (if it can still be pedalled, it won't stop them from riding away, and they could still roll it away walking with it, but coudln't ride under power without a matching plug with wire loop, or magnet, or whatever you used, and knowing that is what is needed to enable the bike).

Do you use your brake levers to help getting over trail objects then twist the throttle to help get over and every now and then you touch throttle when its not needed. amberwolf has a good idea thats often used on powersports like personal water craft. Might be worth trying a few different forms like a big toggle switch, small toggle, push button and try different locations like next to throttle, on brake lever, under seat

cyclokinesis said:

Happy owner of a SurRon but this applies to twist throttles in general.
On a couple of occasions I have stood aside from the bike and gently used the throttle to help push the bike up/over trail objects, such as a vertical cut or big log.
If the rear tire suddenly catches good traction on the object the bike jets forward and naturally, with me holding the grips, the throttle instantly gets twisted and there goes the bike end-over or off on a ghost ride.
I can install a kill switch easily...question is where to put it for these situations...
I'm out of ideas.

Click to expand...

I use a pull cord kill switch like on a jet ski ect.

I use a Oset kill switch, normally closed,when you pull the red button off ( attached to your wrist) it cuts power to the controller.You add it to the key switch circuit.

There are some aftermarket tether switches for atv/snowmachine/ like this...
https://www.amazon.com/BikeMaster-Tether-Switch-Normally-Closed/dp/B0068FYL7E
I like the bombardier selection
https://www.powersportsid.com/bombardier-kill-switches/
Summit racing & Dennis Kirk have magnetic tethers for a little more money.