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[teddillard]

Another piece of the motor/controller puzzle.  I've never really waded into the deep(er) end of the pool on the basic question of speed vs torque control, but I found a good thread on the AEVA forum.  It's more of me "typing myself smart" than I like, but finding a definitive explanation online was damned-near impossible. 

Here's my post: https://evmc2.wordpress.com/2014/12/05/controllers-speed-vs-and-torque-control/

Again (and as always) I welcome some critique - especially on this issue since I: a) really don't fully understand it and: b) would like to. 

c) 

[Cortezdtv]

Sure would seem as if the early bikes (2008-2012 MX/x models) are speed control and the 13s went with the torque,     The older bikes are much jerkier,

I've been told the old controllers worked more like a rc speed controller pushing battery voltage directly through to the motor, where as in the newer bikes 13 and up all the power must travel directly into the controller then out the other side rather than just passing though a "regulated gate" like the earlier speed controllers.

Feel free to correct me just what I was told long time ago by someobe who worked there, and I'm sure there is a chance I relayed it slightly wrong, maybe you can shed some more insight to it Ted


And thanks for another good read for me

[teddillard]

The early Zeros were running Alltrax AXE controllers afaik.  Definitely speed control. 

Not sure on the rest - sounds like kind of a sketchy analogy to me though.  I did a post a while ago on your basic PMDC controller:
https://evmc2.wordpress.com/2011/04/01/how-a-controller-works-so-you-can-see/

Basically feeding the motor pulses of full voltage in varying increments... 

And thanks!  Glad you're enjoying them.  The fruits of my obsession...  lol!

[NoiseBoy]

My 2012 set itself to speed control mode once for a few days then switched back. When opening the throttle it shot forward flat out then stopped accelerating suddenly when it reached the speed determined by throttle position. Fairly unpleasant but it felt faster than normal.

[teddillard]

Sorry to double post - lost track of the threads.  My last installment was looking into the Alltrax SPM controller programming to see if it gives a torque control setting.  It does:
https://evmc2.wordpress.com/2014/12/17/the-controller-thread-last-installment-alltrax-spm-controllers/

[jateureka]

The 2011 Zero uses the Main Bike Board (MBB) to filter the throttle signal before it enters the Alltrax controller.
If you read through some of the threads in the '2012 and earlier Zero' section of this forum you will find posts by Electric Cowboy and Doctorbass where they talk about changing the throttle mapping via programming the MBB. In that software you can change the control from speed to torque or both and the upper/lower limits and ramp rates, etc.

If you don't have a Zero MBB then you could use a Throttle Tamer or Picoamps throttle filter module to convert your throttle signal so that it acts more like a current/power/torque control rather than a voltage/speed control.
http://greyborgusa.com/product/throttle-tamer/
description of operation here http://endless-sphere.com/forums/viewtopic.php?f=31&t=51460
I have purchased one of these to install on the ZEV 7100 LR as the throttle on that is speed control and acts like WOT until it gets to the speed you set with the throttle and so is very jerky and not very nice when compared to my Zero electric bike or my Yamaha MT-07 ICE bike.

You could try building your own throttle tamer if you can solder a circuit or program an Arduino. http://endless-sphere.com/forums/viewtopic.php?f=2&t=78&start=200

[teddillard]

Thanks for the update and the links!  Some good reading there...