To help my aging thumb I decided to swap the existing thumb throttle on my Oxygen MTB to a Half Twist version.

Installtiion was easy, simply removed hand grip and fitted the new throttle, disconnected the original throttle connector (a Julet version) and connected the new one, also a Julet fitting.

Switched the controller on , rotated the Half Twist - nothing... double checked all the connectors and that the new one wasn't being nipped against gear lever clamp etc.

 

This is version I bought... https://www.ebay.co.uk/itm/354733826595

Any sugestions as to what could be wrong would be gratefully received.

TIA

To help my aging thumb I decided to swap the existing thumb throttle on my Oxygen MTB to a Half Twist version.

Installtiion was easy, simply removed hand grip and fitted the new throttle, disconnected the original throttle connector (a Julet version) and connected the new one, also a Julet fitting.

Switched the controller on , rotated the Half Twist - nothing... double checked all the connectors and that the new one wasn't being nipped against gear lever clamp etc.

 

This is version I bought... https://www.ebay.co.uk/itm/354733826595

Any sugestions as to what could be wrong would be gratefully received.

TIA

In the listing, they ask you to check that the pinouts match. Did you? If not, use a meter to check what you have.

 

Whatever the results, cut both connectors off and join the wires to sort it out.

In the listing, they ask you to check that the pinouts match. Did you? If not, use a meter to check what you have.

 

Whatever the results, cut both connectors off and join the wires to sort it out.

 

Thanks for that saneagle.

That could be my mistake, I thought it meant the location of the pins relative to the notch in the yellow plastic not the +, -, signal wires, bad assumption by me that all Julet connectors are wired the same.

Looks like a cut and solder job then, thanks.

Without cutting the wires, does anyone know which of the pin holes in the throttle female connector is the +5 volts and the negative relative to the notch in the yellow plug?

How do I use a multi-meter to check this please.

Without cutting the wires, does anyone know which of the pin holes in the throttle female connector is the +5 volts and the negative relative to the notch in the yellow plug?

How do I use a multi-meter to check this please.

Check two pins at a time with the bike switched on and the motor wheel off the ground. One pair will show 5v. They're the 5v and ground. The other is the signal. If you short the 5v to the signal, the motor will probably spin, which is why you need the wheel off the ground.

Check two pins at a time with the bike switched on and the motor wheel off the ground. One pair will show 5v. They're the 5v and ground. The other is the signal. If you short the 5v to the signal, the motor will probably spin, which is why you need the wheel off the ground.

Many thanks - again.

Solved

Following on from the above posts I have finally managed to install the half-twist throttle to the Oxygen MTB.

As per saneagle's suggestion I cut-off the 3 pin female connector from the half-twist and tested for 5v, ground and signal wires with a 3 AA battery box power supply.

Not wanting to damage the plug on the original throttle cable I disconnected it and left it on the handlebars as a ‘back-up’!

Then checked the pins on the Julet connector on the bike.

Ordered a new Julet female connector/cable from Amazon, shortened it, bared the wires, connected them with some clips to those on the half twist, plugged it in the bike (on bike stand) and tested many times, Sorted.

Disconnected the clips, slid on some shrink-wrap tubes, soldered the cables and shrunk the wrap.

For anyone else who might consider fitting one, these are the wire to wire colours:-

HALF TWIST THROTTLE to JULET CABLE

Purple connects to White

Grey connects to Black

Black connects to Red