Q100 loses power, makes whining noise at low speed

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
Hi all, I finally finished my conversion! After lots of shopping around and delay, I’ve finally built it. I do have one major issue though, which is what I’m here to ask about. When I use an assist setting greater than 3 or push the throttle any more than a tiny amount while below 25 km/h, the bike will pull for a second and then it sounds like the motor and controller de-sync, with the controller running through the phases faster than the motor is spinning. The motor is a q100 cst, the controller is an S09 square wave sensorless torque simulation controller, limited by the LCD to 18 amps, powered by a 48v 7.2 Ah battery. I have noticed that problem sometimes manifests on assist level 3 if the bike does not accelerate quickly enough, for example if going up a hill or into a strong headwind. It seems to happen near the end of the time it takes for the “soft start” function to finish, so I wonder if that is the problem. Any help would be greatly appreciated. I have uploaded a video of the problem to YouTube here. Sorry for the shaky handlebars, starting from zero with only one hand is a bit unstable.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,990
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West Sx RH
What P1 setting do you have and motor winding/rpm ?
 
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Nealh

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Aug 7, 2014
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Despite what some say P1 does have an affect on motor sync pick up in pas mode, I had a similar issue with Q128C until I selected a PI figure that suited best and as near as a damn gave me a correct odo reading.
Though I was using a sinewave controller, not 100% sure but ex member d8veh I think said they don't always work well with sq wave unsensored controllers like the S0*P series ones. So the issue may lie with the controller.

227 indicates hub ratio of 14.2, Akiema or the Q's appear all to have different gear ratio depending on the version and rpm. It was suggested 201rpm Q100cst is 15.7.1 ratio so try a higher P1 figure and play with it, try 240 - 251 and see if it syncs better.

Also which pas disc are you using as the wrong setting can also have an affect.

My money is on the unsensored controller but try the above first.
 

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
Playing around with the P1 setting, 249 seems to be the best so far, allowing up to assist 4 from a stop, and level 5 / WOT at ~16 km/h. WRT the sensor, I forget the name, it’s the one the LCD manual calls “reverse pulse”. S-12V maybe?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Playing around with the P1 setting, 249 seems to be the best so far, allowing up to assist 4 from a stop, and level 5 / WOT at ~16 km/h. WRT the sensor, I forget the name, it’s the one the LCD manual calls “reverse pulse”. S-12V maybe?
That follows suit with 15.7 gear ratio so does sound about right, keep playing up and down by 5 or 6 figures either way and sttle for the one that syncs best whilst riding.

For that pas disc /sensor reverse v12, try C1 setting 05,06 & 07 one should feel better then the others.
 

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
I had it set to 7 before, but 5 feels better. For P1, there’s no discernible difference between 249 and 251, so I’ll keep it there. Thanks for the help, this is a major improvement! So from here do I just stick with this until I decide to spend the money on a sensored controller?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Most likely little more to tinker with to improve settings, however if you post all your C parameter settings as a list 1 -14 we can see if it can be tinkered any more.
 

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
Oh, I just realized I should mention this. I’m going home for the holidays and I’ll be away from my bike from tomorrow until the 7th of January, so I won’t be able to implement any changes until after then. I will keep checking the thread though.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Make the following changes one at a time to feel/try their affect after your hols.
C3 try 0 or 8.
C4 throttle try 0 only activates when pedalling to be legal, means setting P4 to 1
Also P3 make sure it is set to 1 for current control, pas in all levels will have varying current /power levels. Current control is smother then speed control which is 0.
Pas 1 13%
Pas 2 20%
Pas 3 33%
Pas 4 50%
Pas5 100%
Try C5 10 as this gives max current but only on throttle and in Pas 5, in other pas levels you will get the % of the max controller current as in C4 above.
C7 0 this turns cruise off.
C14 is 2 try 3 to see if pas picks up better.
C14 is pas signal strength 1 weak ,2 medium & 3 strong.

Also the pas disc and sensor gap between the two should be about 1 or 2mm at most.

Most of these changes I believe will be for the good and your controller should be ok.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
290
60
73
Chicago, USA
I run two Q100's on 6FET sinewave controllers siilar to the S06 sold by BMSbattery, and another one on the 6FET KT square wave controller . These are dual 36/48 units, No loss of sync.

If DVE8H were still around, I think he would point the finger at your S09 sensorless controller. I have one of those controllers running a Bafang SWXH w/o problems. but it only spins around 4X wheel rpm. I believe our Q100's are 12X, and the S09 cannot keep up. not using discrete hall sensors to determine motor position,
 

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
Sorry if this is too late for the thread, but does anybody know of a sensored torque simulation controller that can do 18 amps then? The reason I’m not running 22 is that from what I’ve read here and elsewhere, that might cook my motor pretty quickly. I’m fairly good with electronics, and I’ve heard that you can solder the shunt in an S06, but what might be the downsides to that? Thanks.
 

harrys

Esteemed Pedelecer
Dec 1, 2016
290
60
73
Chicago, USA
The C5 parameter, if you use the LCD3 display with the KT controller, has settings that can derate the current from 50% to 90% of max. I've never tried it out though.
 

jarob10

Esteemed Pedelecer
Jan 22, 2017
270
83
51
Uk
N
Hi all, I finally finished my conversion! After lots of shopping around and delay, I’ve finally built it. I do have one major issue though, which is what I’m here to ask about. When I use an assist setting greater than 3 or push the throttle any more than a tiny amount while below 25 km/h, the bike will pull for a second and then it sounds like the motor and controller de-sync, with the controller running through the phases faster than the motor is spinning. The motor is a q100 cst, the controller is an S09 square wave sensorless torque simulation controller, limited by the LCD to 18 amps, powered by a 48v 7.2 Ah battery. I have noticed that problem sometimes manifests on assist level 3 if the bike does not accelerate quickly enough, for example if going up a hill or into a strong headwind. It seems to happen near the end of the time it takes for the “soft start” function to finish, so I wonder if that is the problem. Any help would be greatly appreciated. I have uploaded a video of the problem to YouTube here. Sorry for the shaky handlebars, starting from zero with only one hand is a bit unstable.
Not related to your question, but from your video, your rear wheel hub is upside down in the dropouts, risking water ingress through the cable
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,990
8,173
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West Sx RH
Sorry if this is too late for the thread, but does anybody know of a sensored torque simulation controller that can do 18 amps then? The reason I’m not running 22 is that from what I’ve read here and elsewhere, that might cook my motor pretty quickly. I’m fairly good with electronics, and I’ve heard that you can solder the shunt in an S06, but what might be the downsides to that? Thanks.
Buy the KT 20a 36v or dual voltage controller from either PSWPower directly or via Aliexpress. With lcd3 you can limit the controller amps or buy the 17a version instead and leave it set to max amps.
https://www.aliexpress.com/item/36V-48V-350W-Brushless-DC-Sine-Wave-Controller-ebike-Electric-Bicycle-Hub-Motor-Controller-with-right/32759804535.html?spm=a2g0s.9042311.0.0.27424c4dHkpnpu
 

AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
I've looked at what PSWPower has to offer, and maybe I'm just missing the obvious, but I can't seem to find a sensored 48v torque simulation controller. Is the one you linked on aliexpress a torque simulation controller? The listing doesn't mention that it is. On BMSBattery the only sensored torque sim. controllers are the 6-FET and the 12-FET, which I suppose I could settle for, but I would need either to over-amp or get a larger controller and saddle bag.
 
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harrys

Esteemed Pedelecer
Dec 1, 2016
290
60
73
Chicago, USA
PSWpower was selling 20A sensored torque simulation controllers two years ago, as I have one from them, but I agree that they don't sell them now.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,990
8,173
60
West Sx RH
All PSWP sinewave (sensored ) controllers can use speed control or torque control, you have to set the P3 value accordingly.
In torque mode each PAS level gives you more amps/torque.
For 20a controller, all are approximate.
PAS1 2.6A.
PAS2 4A.
PAS3 6.6A.
PAS4 10A.
PAS5 20A.
 
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AviatorTrainman

Pedelecer
Feb 9, 2018
35
6
23
Arizona, USA
Sorry again for the late reply, but I eventually just went ahead and got a 12 FET controller before I saw your comment about all sinewave controllers supporting torque simulation. That was stupid of me. It's too big for the saddle bag, but is otherwise working perfectly for my purpose with one exception: I can't seem to find a combination of P3 and C4 that make the handlebar throttle torque simulation. It is always a speed throttle, even though the PAS is torque simulation. I can live with this, though it is inconvenient. I appreciate everybody's help, I'll definitely come here more often! I realize I never uploaded a complete picture of the build, so here is one with the old controller that fit in the bag. The "much better" refers to the battery I have just put on, which is a re-packaging of the original one I made into the blue water bottle. I made the battery because I now live in the US where black Friday is a big event, so I got 26 LG MJ1 cells for 85 USD and a Sunkko 737B for 65 USD, which adds up to less than the cost of a fresh battery. It currently has an XT-60 plug, but the plan is to eventually have copper contacts on the bottle and cage connected to wires which run in through the centre of the mounting bolts and up the seat tube. The bike is in its winter form right now, with wide CX tires and fenders, but in the summer it gets narrow road tires and the fenders are removed.IMG_3643.JPG