Walking speed button

[urosv]

Hi All,
I want to add walking speed to cruse button. The idea is when I push and hold the cruse button Magic Pie will help me move and get a speed around 2-3km/h, to walk by. How can I tweak a throttle to bay-pas some small amount of speed ?
Thanks for help...

[Bikemad]

How can I tweak a throttle to bay-pas some small amount of speed ?

It's relatively simple to modify the throttle to suit your requirements by simply fitting a couple of small diodes and a small variable resistor (10K trimmer) as shown here:



The trimmer would have to be adjusted by trial and error to obtain the desired speed.
If you don't have a horn, you could use the wires from the horn button instead so that your cruise button will control the cruise function as normal.

Please Note: The throttle will still continue to function as normal and would still deliver full power if accidentally operated.

I couldn't remember what colour wires are used on the horn/cruise unit so the colours shown in the above diagram are not correct.

Another alternative would be to use the throttle restrictor circuit shown below and simply set the maximum speed to walking pace and then use the throttle instead of the cruise/horn button for variable slow speed control.



The square red button on the throttle control can be used to turn on/off the restricted throttle instead of the single pole switch shown in the diagram, and another 5K trimmer can be used in place of the 5K potentiometer shown if preferred.

Alan
 

[urosv]

Excelent,
I will try this today and give you a feedback !
One question in between. What is inside throttle? Is controler sending current through and throttle is variable resistor, and how does HAL signalling work ?

[Bikemad]

What is inside throttle? Is controler sending current through and throttle is variable resistor, and how does HAL signalling work ?

The throttle incorporates a hall effect sensor, a small device which determines the actual position of the rotating twistgrip/thumb lever by sensing the movement of an embedded magnetic strip. The hall effect sensor converts the varying magnetic field into a variable voltage output which the controller then uses to control the amount of power being supplied to the motor.

Take a look at this post to see exactly what's inside the throttle unit.

Alan
 

[mike662]

How can I tweak a throttle to bay-pas some small amount of speed ?

It's relatively simple to modify the throttle to suit your requirements by simply fitting a couple of small diodes and a small variable resistor (10K trimmer) as shown here:



The trimmer would have to be adjusted by trial and error to obtain the desired speed.
If you don't have a horn, you could use the wires from the horn button instead so that your cruise button will control the cruise function as normal.

Please Note: The throttle will still continue to function as normal and would still deliver full power if accidentally operated.

I couldn't remember what colour wires are used on the horn/cruise unit so the colours shown in the above diagram are not correct.

Another alternative would be to use the throttle restrictor circuit shown below and simply set the maximum speed to walking pace and then use the throttle instead of the cruise/horn button for variable slow speed control.



The square red button on the throttle control can be used to turn on/off the restricted throttle instead of the single pole switch shown in the diagram, and another 5K trimmer can be used in place of the 5K potentiometer shown if preferred.

Alan
 

I want to do this for my non-mp kit. Will this work, or is this only for mp? Thanks!

[DirtyGinge]

This mod should work with all 5V hall sensor throttles

[mike662]

This mod should work with all 5V hall sensor throttles

Thanks dirtyginge!

[mike662]

I made a video that shows the speed reducer working, in case anyone would like to see how it works.

http://www.youtube.com/watch?v=Z-7zCNNRxkI

[Bikemad]

Nice video Mike, it clearly demonstrates how effective this modification is at limiting the maximum speed of the motor.

Alan
 

[motor_magic]

Has anyone got this working for MP3?  If so any chance of a diagram?

Cheers,

Neill

[urosv]

Reverse switch, 100% functional.

[Bikemad]

Reverse switch, 100% functional.

I don't understand why the time delay is required, why not simply join the two wires to select reverse?

Has anyone got this working for MP3?  If so any chance of a diagram?

Neill,
I don't think anyone has tried this on the MPIII as it would require some very intricate soldering.

The neatest way to accomplish it would be to run a separate piece of two core cable into the throttle control and then cut the green signal wire coming from the hall sensor and solder the two separated ends of the green wires onto the two core cable:



There is very little spare room inside the throttle housing so it would be a bit of a fiddle to do it neatly and properly insulate the soldered joints.

An alternative method would involve carefully cutting into the insulation on the existing throttle cable and exposing the green wire so it can be cut and the two core cable spliced into it part way along the cable run.

Unless you have a very steady hand with a very sharp knife and good soldering skills, don't even consider doing this modification, as you would probably end up ruining a perfectly good throttle.

Also, I can not guarantee that the throttle signal wire will be green on all MPIII throttles, so you would also have to check very carefully before cutting any wires.

Alan