Bike keeps shutting off on my commute home, Help? Full Specs Here.

[500wattz]

I have a stealth bomber clone that came with a mideuebike rebranded dinky 80/300 controller. I bought the bluetooth dongle (didn't come with one) so i could further tune it in the fardriver app but due to my over-excitement, I didn't save the stock tune before my issue started happening. At stock tune, my bike never tripped. It never shut off on its own, ever. But it was a snail off the line at full throttle, and it was a horrible hill climber. It caught up to speed though, hitting 90kmh on flat on full charge, no problem.

I use my bike primarily for work commute, which is 41km mostly straight and downhill with some hills, then 41km home which is mostly uphill, 82km round trip, 5 days a week if the weather permits it, all year long. I am a heavy rider, at 250lbs before full moto gear. The bike is a fat tire bike, so it's heavy, probably around 160-180lbs with a steel frame.

Because my controller is old and no longer supported (according to siaecosys) I can't change a lot of the settings as I get the "please use new BLE module" message. Siaecosys says the USB cable will work, so I ordered that and am awaiting it's arrival, but for now I have to make due with what I have. I can't change pole pairs, some RPMs in speed ratios, stuff like that.

Ever since I started my goal to achieve 5kw (70/200) The bike always trips and shuts off around the same spot going home, going up a hill. It shut off once waiting at a red light which was really odd. It NEVER shuts off going to work, where I hammer the throttle and burn more battery than going home due to the speeds I'm going.

Controller has gotten as hot as 77-80c, motor around 45c (i use temp laser gun for that) and battery around 45c (temp laser gun for that as well). The controller is too hot to touch, the silver area especially once I get home.

Could it be the controller overheating? I get the undervoltage alarm but I think that's just the app losing signal from bluetooth since the entire bike shuts off when this happens, display, controller motor and all. When this does happen, I pull over, wait 3 seconds, turn the bike back on and it works no problem gets me home which is a remaining about 6km from that point. I also don't think it's undervoltage alarm because my 72v battery sags to around 72-73v around there when this happens and on the way to work, I've sagged it to as low as 67 at times and it never tripped. The line amps were also under 40 when it trips due to my battery being at 60% or under.

So what could it be? I plan to get a ND72530 very soon just to run the thing at under half capacity as i would think that wouldn't heat up as much since it'll be under utilized, at 70 line, 200 phase around there.

Here are all my pics, motor, bike, battery, controller settings (limited), a screenshot when it tripped, and all that.

My battery is a Suzhou thinked electronic technology 72v 41ah 150a BMS (I think, had to translate from google lense), 2999 watt hours. Battery currently has around 4300km of usage. I don't know if it has bluetooth BMS.

Please note, I have changed a few settings since these screenshots. I have changed motortemp sensor to none, as CACU wasn't reading properly, maxrpm set to 5000RPM, low voltage protect at 63v, line current 70, phase 200. Field weakening is disabled (can't change it) and regen also disabled (i ride in winter, so should stay that way).

Thank you all in advance!

 

[m3vuv]

battery goosed i would guess,take voltage readings under full load.

 

[500wattz]

battery goosed i would guess,take voltage readings under full load.

Not the battery. I have a voltmeter on my throttle, soldered it in myself. Line amps under 40 and voltage over 70v when it trips, never trips under full load (70a line). I think it's the controller overheating. Getting a Nd72530 today.

 

[From-A-To-B]

Sounds like you are well on your way to the first step in troubleshooting your own problem. Your controller was getting HOT, and the replacement may or may not solve your problem. Hopefully it does!

Keep an eye on battery and motor temps as you push more current through your system. They’re already heating up, and you only have 40-50*F worth of thermal budget to work with.

 

[500wattz]

Well I made it home at 70/210 using the brand new ND72530 and it did not trip! It still got a wee bit hot, at 77c but I'll tinker with it, probably my speed ratios as i set them all to 100. It was nice experiencing a sustained 70 line, 5kw all the way home with all that elevation with decent torque. I tried 70/300 on the way to work and holy crap it was insane. I had to tuck the handlebar into my gut on takeoffs! too much...melting my brake pads.

Thank you so much to those who put in their input on my thread.

I believe the issue is now resolved

 

[neptronix]

If you're measuring up to 80C on the case of the controller, there's spots at 100C or above inside, and that's when most electronic components start to get unhappy.

I would seriously consider dialing the power down 5% and seeing what happens. If you don't see under 70C, dial it down another 5%, and so on, otherwise you will probably see a short controller lifespan.

 

[Bikestick]

I have had 1 controller take a crap but I have learned to alway get a slightly oversized battery so the BMS dosnt shut down from over discharge.

 

[500wattz]

If you're measuring up to 80C on the case of the controller, there's spots at 100C or above inside, and that's when most electronic components start to get unhappy.

I would seriously consider dialing the power down 5% and seeing what happens. If you don't see under 70C, dial it down another 5%, and so on, otherwise you will probably see a short controller lifespan.

Hi.

I've created a makeshift vent system on my side panels on my bomber which now allows ventilation. I haven't seen the controller go above 65c since. Only issue now is I have to gorilla tape the vents when I want to ride in the rain, which then I have to be mindful of how much power I output to prevent overheating.

I've only had a heat issue once. I got to work once and my battery wouldn't charge. I waited 1.5 hours for it to cool down, still wouldn't charge. I disconnected the anderson connector (which resets the bms) and then it charged. It has been fine since. I believe the lack of ventilation (this was before I made my mod) was causing the battery to exceed 45c, at which the bms won't allow the battery to charge until it cools down.

Since my mod, I haven't had any issues, yet.

 

[500wattz]

I have had 1 controller take a crap but I have learned to alway get a slightly oversized battery so the BMS dosnt shut down from over discharge.

Cool. I haven't had any issues since the controller upgrade. I do believe my issue with the stock controller, was that controller overheating or something within the bugged tune that was causing it to do it's thing.

 

[calab]

Measure each parallel grouping for voltages when the battery is at LVC and see how far off each grouping is.
I'd be sure to measure it as soon as possible after a hard ride up a hill.
To cheap out, others have bought a 6-8s lipo voltage reader, and used 2 or 3 of them at once to get real time data points.
Bluetooth bms is a nice feature to read the voltages of each pairing/grouping.
Next I'd look at the parameters of your controller, in the software if yours has one. If its just generic, then it might be something broke loose, but I'd first look at all the wiring, phase wires from the just inside the axle exit, wiggle the wires pull out a bit, sometimes frayed phase wires hide in the axle exit. That would be a symptom of a random cutout after a bump, if not fry a fet. But I'd open the controller and take a visual of the components for marks, black, note any aroma coming from the vintage.

 

[500wattz]

Measure each parallel grouping for voltages when the battery is at LVC and see how far off each grouping is.
I'd be sure to measure it as soon as possible after a hard ride up a hill.
To cheap out, others have bought a 6-8s lipo voltage reader, and used 2 or 3 of them at once to get real time data points.
Bluetooth bms is a nice feature to read the voltages of each pairing/grouping.
Next I'd look at the parameters of your controller, in the software if yours has one. If its just generic, then it might be something broke loose, but I'd first look at all the wiring, phase wires from the just inside the axle exit, wiggle the wires pull out a bit, sometimes frayed phase wires hide in the axle exit. That would be a symptom of a random cutout after a bump, if not fry a fet. But I'd open the controller and take a visual of the components for marks, black, note any aroma coming from the vintage.

Issue has been resolved once I went ND72530. Not gonna bother with the rebranded unknown old fardriver "miduebike" crappy controller my bike came with.