Please HELP me!!

[provo]

I am really confused and have a serious problem here...

This morning I plug in my magic pie 3 equipped bike to my 48v battery, and the thing basically takes off at 400w (not exaggerating saw the reading on my cycle analyst)!I managed to lift the back wheel fast enough to not let it pull it away, but I had to literally put it against a concrete wall and have it do a burnout for 3 seconds as I reached over to immediately unplug the battery pack!(later thought laying down may have been better but I had to think fast at that moment... and was not sure if the wheels would still touch the floor as I have never laid it down.) This was my worst nightmare and I cannot believe it has actually happened! It wasn't an immediate 400w though. At first I plugged it into the pack and noticed it was twitching or slightly moving every now and then, maybe 5/10 watts. I observed for about 2 minutes and figured it was nothing serious so I started getting ready to get on it when it took off all of a sudden!

This is the fourth time I have plugged it in and I was planning on doing a long trip today and am now extremely confused. Everything is brand new, and I have rode it successfully for about 20km three times without a problem, including going steep hills at 1200w and leaving it outside unattended while plugged in for hours.

So first thing to comes to mind: Yesterday I rode in moderate rain (no problems during the ride).

Anybody please any ideas?

This is the setup: 48v 20ah lifepo4, magic pie 3 (26") with internal controller, thumb throttle. Cycle analyst (but not really relevant I guess as it is not controlling anything.)

Worth noting: When I used the ebrake/regen it cut the motor, as I let go of it though immediately the motor takes off intermittently or full 400w at times, but again it would immediately cut any wattage the second I used one of the two ebrake levers. Also if I used the throttle, even slightly, it would not surpass the input I was giving it (stable when using throttle normally). Only when everything is at rest does it do it.

Please help!

Much love.

 

[Jeremy Harris]

This happened to me a few months ago, different motor, different controller. In my case it was a bit of water in the controller. No harm was done, and after drying the controller out it worked as before.

When I took mine apart to see what the problem was, it was clear that there was a tiny bit of water around the throttle connection area on the circuit board. This was enough to provide some voltage to the throttle input and make the motor do pretty much exactly as you describe with your MP3, twitch a bit, then power up and go.

 

[Trackman417]

Take the throttle connector off and then turn the system on again. If it doesn't tale off, odds are its the throttle. Maybe some water shorted the ground with the 5V wire? I use dielectric grease on all of my connectors. No chance to get water in between them to short any wires.
Hope this helps

 

[provo]

Very interesting responses... I really appreciate the input. Am looking into both of your suggestions as we speak.

I must say: this was a truly scary moment! Lifting the back of the bike is a feat in itself as I had two 48v 20ah pack on the rear rack plus the heavy mp3 motor, and no good place to anchor my hand to lift only the back and not front wheel. Unbelievably shocking, as I was really not expecting after the other times where it worked fabulously!

Any other ideas/suggestions will be considered!

I love endless sphere and all of its members. You guys (it is) one of the best online communities I have ever come across.

Many thanks!
Much love.

P.s.: (Sorry if my English is not perfect, it is my second language. I would appreciate any constructive criticism)

 

[provo]

So I unplugged pin 3 (throttle) from the control cable hub that comes with mp3, and then proceeded to plug in the 48v pack.

Result: 2 tiny twitches not even a reading on the CA. I waited and nothing more. I then proceeded to blow inside the male and female portions of the throttle cable (very nostalgic moment: Anyone else ever have to do this continuously with their NES, SNES or N64 game cartridges!) and nothing happened over the course of a few minutes even with the throttle plugged in.

As I unplugged the throttle there was droplets/moisture inside the connectors.

I believe this has been resolved.

Dielectric grease on my list of things to buy.

Much love,
Zach

 

[dnmun]

you should disconnect the leads with battery voltage in your throttle if it is leaking current onto the throttle signal wire when there is moisture. hi voltage, sensitive microamp inputs to the microprocessor and moisture is a bad combo.

 

[Trackman417]

This happened to me a few months ago, different motor, different controller. In my case it was a bit of water in the controller. No harm was done, and after drying the controller out it worked as before.

When I took mine apart to see what the problem was, it was clear that there was a tiny bit of water around the throttle connection area on the circuit board. This was enough to provide some voltage to the throttle input and make the motor do pretty much exactly as you describe with your MP3, twitch a bit, then power up and go.

Btw, sorry Jeremy. Didn't mean to steal your thunder, it took me a a good 15 minutes to finally type up what I wanted to say .

 

[provo]

Good news and bad news.

Seems it was moisture/water in the throttle pin after all so I dried it out and everything was working flawlessly!

I managed to make my longest trip ever on a bicycle yesterday: 95km using an average of 7.3wh/km!

Bad news: I was riding back home today (few hours ago) and with about ~60km (of the ~90km trip) left something happened.

All I can say/have checked is this:
Battery pack is fine, 52v and around 13ah left (voltage is from cycle analyst that is still functional)
The thumb throttle and the regen levers are unresponsive.
All three lights are on on the battery indicator integrated with the thumb throttle (yellow red and green are on steady)
Motor housing and controller were just slightly above ambient temperature at the time of the mishap (it has gotten much warmer on other rides).

Here is how it happened:
I was going about 30 km/h and had been for about 15 seconds when I felt the throttle/motor simply let off. The motor was not producing any more power... So I immediately pulled over and made sure that the throttle was indeed having no effect (which was confirmed.) I then pedaled up to about 20km/h to see if regen was functional and it was not. Then I tried unplugging and re plugging the throttle pin and it worked! So I took off again and had the same problem about 35 seconds/150m later.

I had to call a buddy to come pick me up. I really owe him one as it was a 2 hour drive...

Had a blast on my first ride though... Wow what a machine!

I will appreciate any suggestion/questions.

Much peace and love!

 

[iamsofunny]

I had this problem and it was the connection between battery and controller because it had arc slag on it. I just filed it off the plug and it works now.
Your controller could be fried though. If I went more than 30km per trip I'd carry a spare throttle and spare controller in conjunction with the tubes and wrenches that I carry now.

 

[provo]

Thanks for the input iamsofunny...

My controller to battery connection is across the cycle analyst shunt and the wires soldered together, so I think that eliminates your first suggested scenario...

Could there be arc slag on my throttle plug/connector (what does it (slag) look like and how would you file it down when the pins are so deeply recessed in the plastic plug housing)? One of the pins seems slightly darker than the others...

Why/how could my controller be fried? does this just happen at random sometimes?

Would appreciate any input!

Much love