How exactly do 3 speed throttle switches work?

Fordulike

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Feb 26, 2010
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I realise that the job of these switches is to provide a 3 stage speed limit, but how do they do this?

Say the bike operates like this:

position 1: 8mph
position 2: 12mph
position 3: 16mph (full speed of bike)

When the bike is speed limited in position 1, does the throttle spread this over the full turn of the throttle, and do the same with position 2. Obviously, 3 isn't altered in any way.

Or, does it cut off the upper range of the throttle turn to provide the speed limit.

This might sound a bit gobbledygook, but hey it is Sunday morning :eek:

Also, does the speed switch limit available torque in position 1+2?
 
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flecc

Member
Oct 25, 2006
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A common way of doing this is with resistances. The eZee EAF multi-position control works this way, as does the "Cruise Control" that Dave (d8veh) created for his bikes to operate to various fixed speeds. In effect this provides part throttle levels, equivalent to not twisting a twistgrip throttle as far.

The torque at the lower intermediate speeds reached isn't changed, it follows the same pattern of being higher with lower speed.
.
 
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NRG

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Oct 6, 2009
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I realise that the job of these switches is to provide a 3 stage speed limit, but how do they do this?

Say the bike operates like this:

position 1: 8mph
position 2: 12mph
position 3: 16mph (full speed of bike)

When the bike is speed limited in position 1, does the throttle spread this over the full turn of the throttle, and do the same with position 2. Obviously, 3 isn't altered in any way.

Or, does it cut off the upper range of the throttle turn to provide the speed limit.

This might sound a bit gobbledygook, but hey it is Sunday morning :eek:

Also, does the speed switch limit available torque in position 1+2?
The switch scales the throttle movement so with your example of position 1 giving 8mph or 50% of position 3 it means full operation/rotation of the throttle in position 1 gives 50% of the available battery voltage to the motor...hence half the speed.

The torque more or less remains the same. To provide true torque control you need to vary the available amps to the motor.
 

Fordulike

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Feb 26, 2010
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Thanks flecc and NRG.

So in reality, position 1 should give better controllability of the motor at low speeds, because it spreads the lower speed range over the whole of the twist of the throttle?
 
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flecc

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Oct 25, 2006
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Yes, it partially overcomes the familiar problem of the fierce on/off nature of our Hall throttles in that way, though the hall action will still be fierce. I wish some manufacturer would make a high quality potentiometer twistgrip throttle to give even better motor control over the whole range. I've often toyed with the idea of making a multi-step twistgrip throttle with at least a dozen fixed resistor steps but never got round to it. Alternatively making a bevel gear drive for a high quality potentiometer would be even better.
 

mike killay

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Feb 17, 2011
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The throttle on my electric outboard has click stops, five forward and three backwards.
Just thought I would add that!
 

flecc

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Oct 25, 2006
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That makes a lot of sense on an outboard Mike, not much point in absolute precision.
 

Fordulike

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Feb 26, 2010
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Does anyone know if the Cycle Analyst speed limit function, limits the speed in a similar way?
The direct plug in plus speed sensor type.
 
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