Nanrobot D5+ 2.0 Mystery solved!! Brush less motor dissection, trouble shooting and speed accuracy. 

Since there aren't any hall effect sensors (typically 3), your motor controller is using back EMF to determine when to commutate the motor as well as calculating your speed. Speed controllers drive 2 of the 3 phase wires in 6 different states with MosFETs, one driven with battery voltage and the other ground. The phase wire not driven goes into some electronics on the motor controller (resistors, caps, and op-amps) and it senses the back-emf. The designers use this info not only to know when to commutate the next phase of the motor, but uses the MCUs timer to calculate wheel speed. It measures the time in between the EMF pulses and based on the diameter of the hub and tire calculates your speed - 2*PI*R * time for one rotation ( 3 EMF pulses). Google back EMF for more detailed information on the topic. Same as Ale's comment below....

Damn that was a learning experience! Thankyou for taking the time to explain this in depth. I learned more with this video than I learned in all my HS science classes combined

Great video, thanks for sharing. I found some time to take my wheels off today and installed the tube liners, I took my time because I wanted a clean fit, with no over or underlap, got it back together, and took it for a couple spins around the neighborhood, all good bro. Yea thanks for the heads up on making sure it was cut to the right length to avoid speed wobble in the tire. I feel better running on puncture proof or at least puncture resistant tires. Cheers man!!

Great content as usual. Subscribed. I built esk8 for a while and was curious to see these escooters open up. I am also going to modify mainly the electronics of these scooters. You can get more out of them. Since you asked, her efew clarications. I hope useful for everyone. The brushless motors used in escooter and skate for instance are not DC, that's one of the reason why there is a speed ccntroller to talk with them. They are powered by a battery (DC) but they are 3 phases motors. Regarding the hall sensors they are, as you said, telling the speed controller (ESC) the position of the sensors in angle related to the stator and are used to smooth out the take off when starting from stand still. Then they have no use anymore. Sometime there is also a temp sensor on it to read motor temp to prevent overheating (you can implement that, sensors cost like 5$). Concerning your correct question how the speed is calculated then the speed is based on RPM or to better say Engine RPM (ERPM). The ESC reads the back-emf and count it as 1 rotation (you can read here from an open project for advacne ESC that we used in esk8 vedder.se/tag/esc/). Since is ERPM then the size of the motor matters so you have to know the number of poles of the stator. The conversion of these values plus the size of the wheels combined with the 3.14 constant (circonference) will tell you the speed. That's why on your dashboard you can set the wheels diameter, but actually to be correct it should have the number of poles as well in order to adjust them and get the right speed. I hope it can help and thanks for your content!

'This is my scooter, there are many like it but this one is mine' ~ Slogan of the Future Marine Stealth Invasion Vehicle poster.

Hmm. Do you think the D4+2.0 motor is the same (no hall sensor)? Changing the hall sensor reading seems much more logical. SUCH a good call, man.

Have you delt with a rear tire on a e scooter not having any rotation when you manually turn it and when you try to use the throttle?

Great videos, thank you. Btw. please, make a video about what is inside of Nanrobot lower tube.

hello good I want to ask you a question I have a D6 because the air chamber deflates every so often, I check it and it has a minimum hole on one side, I mean, it drills it then I put a new air chamber and it continues the same I roll like 20 min and then deflated a little hole you will know what the problem is, thank you very much

Hello again. Been a while. I finally had my first flat tire on my D5+2.0. It was the rear. I live in NYC. I ride every day to and from work, in the rain, and recently in the snow. Well on my way home today I had to cross the 59th street bridge ( using the bike lane ) and there was some kind of nail or bolt, spiky thing ( no point on it ) sticking out and I didn't see it. All I heard was the explosion of my rear tire. Luckily I was not going too fast. The piece of metal snapped off and stayed inside the tire. When I replaced the tire and tube it fell out. Anywho, I was hoping to also change out my rotor which is bent, but after taking the real wheel apart I realized the rotor sits on the cable side of the wheel. Do you have any idea how to take it off without having to cut the cables? If so any chance of you making a video on that process? As always thank you so much for you educational videos. I've learned so much from your efforts and I truly appreciate what you do!

I have been having problems with my scooter. It is not even 1 year old, and when I ride it, it makes this vibration from the rear wheel, and it overheats causing a puncture in the inner tube. Over 1 month I replaced the inner tube 3 times. Is there something I can do

Very helpful! What is the p2 setting you found to get accurate speed? mine seems to be 17 18 or 19 but I'm not certain because I can't look at my phone while I'm riding, I don't have a mount set up

Can u do one how to change a motor on nanrobot

love ur videos man...does nanrobot even have a legit american tech guy for troubleshooting cause I've sent him my issue with video evidence and he said he would jus look into it and that was a month ago...my issue is jus odd like the motor is overvolting at hard throttle from start and makes a plastic grinding noise...any thoughts?

Hi, I also set up my P0 to 6 and the speed is quite accurate ; Did you finally changed your settings (P0, P2 and P3) in order to be as accurate as possible ? I missed the point Thanks

My rear motor is on the fritz. It engages for about one second and then it quits and it feels like it’s rubbing on something like the magnets are in the right place just a little off I don’t know I haven’t gotten into it yet but there’s a warning indicator light that I can’t seem to find with the indicators I don’t know where they’re at in their instruction so I’ll keep looking. thank you

Speed sensor could be in the back wheel? Since single motor mode is just the back wheel. Just and idea

How hard would be be to replace the bearings on this model?

This is fantastic information. Other than the bearings these motors should last a long long time right? So theoretically how long could it last with a quality set of bearings? I didn't get to finish the video. Just saw the first 10 minutes so forgive me for a lack of information.

It may be on the other motor....

can you provide summary? set P0 back to 10 then P2 to?

Dang maybe I should lube or grease those wheel bearings

Are you a electrical engineer? Just wondering

You said in ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9Pzyjyexfjc.html 12:12 those black thingys are 6 sensors I guess that was before you opened up the motor. What do you have P2 set now to?

Stop scraping the cap against the insulation on the wires!