# Needed a tow home.



## madderscience (Jun 28, 2008)

I believe the curtis controller has a feature called "high pedal lockout" or something similar which basically means if you turn it on and the throttle sensor is not at "zero" throttle (I forget whether that is zero of 5k ohms) then it won't turn on. Anyway, that is kind of dangerous, akin to starting a gas car with the accelerator linkage stuck. If you were to try starting the motor in neutral you risk over-revving the motor when under no load, even at very low throttle so don't try it.

What is wrong with the PB-6? I have one and it is built like a tank so far as I can tell. The only things that seem like could go wrong is eventual wearing out of the pot itself or the microswitch failing, or the spring breaking.

A 0-5k pot is not an uncommon part though a truly high quality one you would probably have to search around for a bit. You should be able to find a cheap one at radio shack or someplace similar and wire it up as a temporary knob-actuated throttle assuming the pot is not mechanically compatible with the original one. If the pot is mechanically compatible you would of course just open up the potbox and replace the original with it and drive away.


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## gojo (Feb 1, 2011)

madderscience said:


> I believe the curtis controller has a feature called "high pedal lockout" or something similar which basically means if you turn it on and the throttle sensor is not at "zero" throttle (I forget whether that is zero of 5k ohms) then it won't turn on. Anyway, that is kind of dangerous, akin to starting a gas car with the accelerator linkage stuck. If you were to try starting the motor in neutral you risk over-revving the motor when under no load, even at very low throttle so don't try it.
> 
> What is wrong with the PB-6? I have one and it is built like a tank so far as I can tell. The only things that seem like could go wrong is eventual wearing out of the pot itself or the microswitch failing, or the spring breaking.
> 
> A 0-5k pot is not an uncommon part though a truly high quality one you would probably have to search around for a bit. You should be able to find a cheap one at radio shack or someplace similar and wire it up as a temporary knob-actuated throttle assuming the pot is not mechanically compatible with the original one. If the pot is mechanically compatible you would of course just open up the potbox and replace the original with it and drive away.


The motor was running by itself when I turned on the controller without stepping on the pedal, so I think the cut out must only work with a dead short (0), or I think again after 5.5k, but not in between. I was actually driving for awhile with the motor humming along at whatever the pot was stuck at and shutting off the controller when I needed to stop. I almost made it home, so that is why this crazy idea appeals to me. If I could match the resistance my pedal was stuck at, it would be perfect. 

I don't have a PB-6 in the car now. It is some cheap Kelly or something. I am replacing it with the Curtis FP-6, and everyone seems to be out of them. Is there a difference between a FP-6, and a PB-6? The pot I ordered is a Curtis FP-6. update. Ok, I checked it out, the PB-6 is just the pot box with a linkage, and the FP-6 is a box with a pedal attached directly to the pot box. 

It might be interesting to take the old pot apart, and see if I could fix it. The pedal still goes up and down, but it feels different now. Not as smooth as before.


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## madderscience (Jun 28, 2008)

Huh- OK. Either your throttle pot is not at a setting such that the high pedal lockout will be triggered, or I am full of hot air.

I looked at a picture of a curtis FP-6. There is a difference between that an a PB-6 (which I thought you were talking about) The PB-6 is a just a box with a lever arm on it, it is intended to be attached to an existing pedal and throttle linkage, whereas the FP-6 completely replaces it. This is kta's page for the PB-6:

http://store.kta-ev.com/curtispb-6potbox.aspx

Do you know how your existing throttle box is broken? Still the case that it may be repairable.


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## greif (Jun 26, 2010)

http://www.evdrives.com/throttles.html

looks like there is a pb6 in stock here, I bought my stuff here and am happy with service

gary


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## Ziggythewiz (May 16, 2010)

I've had a couple times when I had issues with the throttle, and for such a simple little thing it's really annoying. I think it would be cool to have a twist throttle on hand for emergencies, such as the one at the site linked above, or even better as a hand lever thing like those stress/hand exercisers. Wouldn't want to pay $50+ for a backup that sits in the glovebox though.

Maybe just get a length of wire hooked to a switch and a 1k ohm resistor; limp home for $5


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## gojo (Feb 1, 2011)

greif said:


> http://www.evdrives.com/throttles.html
> 
> looks like there is a pb6 in stock here, I bought my stuff here and am happy with service
> 
> gary


Thanks Gary, but I'm looking for an FP-6. It's the one with the pedal attached directly to the pot; all one unit. 

That is a really good price on a pb-6 though, and if they have good service I will keep them in mind. 

Don


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## gojo (Feb 1, 2011)

Ziggythewiz said:


> I've had a couple times when I had issues with the throttle, and for such a simple little thing it's really annoying. I think it would be cool to have a twist throttle on hand for emergencies, such as the one at the site linked above, or even better as a hand lever thing like those stress/hand exercisers. Wouldn't want to pay $50+ for a backup that sits in the glovebox though.
> 
> Maybe just get a length of wire hooked to a switch and a 1k ohm resistor; limp home for $5


Deranged minds think alike. Whatever my pot stuck at was perfect for limping home. I think I will pick up a 1k and 2k, then try the 1K first, and if that isn't enough, try the 2k. For now I just want to move the car out of my way while I am waiting for the replacement accelerator, and then keep the resistor in the glove box for future possible problems. I hate being towed home.


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## Conelrad (May 23, 2009)

Howzabout this:

In the beginning, mount a separate pot & knob in the dashboard labled 'throttle'.

Have a DPDT switch also mounted there labled 'accelerator' & 'throttle'.

Wire accordingly so you have two sources of control. 

Limp away.

DG


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## cruisin (Jun 3, 2009)

gojo said:


> My electric converted RX7 broke down a few days ago about ½ mile from home, and a friend pulled me home.
> 
> Turns out the accelerator pedal failed. The car is sitting in the garage, everyone is out of Curtis FP-6's, and it will be almost a month before I can get a replacement. This has got me thinking:
> 
> ...


Everybody knows those pots cannot be trusted. I have put in about 10 of these without a single failure. they also have a NO switch builtin. I use them for the regeneration brake pot as well. here are a couple of pictures.


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