Stand up faggio EV 3.7kw 16s

Have a look for me how the main sprocket shaft is secured to the rotors laminated plates under the magnets I expect its an interference fit with a splined shaft.
It slipped under full load pulling off I backed off a bit got some speed the load had dropped and it performed as normal, I then drove the motor warm before trying to give a full throttle start again and it was fine, I'll investigate it more tomorrow.

This is what happens when you overdo the over watting of your BOMA motor, leave the vent covers in place and they get clogged up so your blower can't keep the motor cool. I discovered something amazing when this happened. Apparently wires have magic smoke in them too. I thought it was just electronics, but I was very wrong. If you don't know the facts, let me set you straight. There is no such thing as electronics. Computers, power supplies, mosfets, TV's, microwave ovens, brushless motors...you name it...doesn't matter...they all run on magic smoke. Intel doesn't design CPU's, they just compress magic smoke into creative new packages and call it a CPU. Samsung doesn't make TV's...they cram little tiny bits of magic smoke into stuff and then wire it all together to look impressive when it's really all just magic smoke. Anyway, this is what happens when you accidentally let the magic smoke out of a motor. Obviously it stops working because there's no more magic smoke inside. I can tell you from personal experience because I watched the magic smoke come out of this motor and once the smoke was all gone it didn't work anymore. Why did I have to push those magic smoke bits just a little bit harder? I should have known when I started smelling tiny bits of magic smoke that I should back off, but I didn't.

I hope you laughed...

OK so onto a more serious note...

I forgot I also had the burned out 1500 watt motor taken apart. So here are the armatures side by side. Stators are the same lengths as the armatures.



Closeup of the motor shaft going into the armature. I doubt those teeth on the shaft are going to slip.





Since I had the armature in my hands, I thought I would check a few dimensions.

Sprocket flats. These have stuff on them so they are reading a little thicker than reality which should be 8mm.


Sprocket round surfaces...10mm



Bearing shaft OD...12mm


Shaft to armature OD...14mm


Armature OD...50mm

Ianhill said:

Have a look for me how the main sprocket shaft is secured to the rotors laminated plates under the magnets I expect its an interference fit with a splined shaft.
It slipped under full load pulling off I backed off a bit got some speed the load had dropped and it performed as normal, I then drove the motor warm before trying to give a full throttle start again and it was fine, I'll investigate it more tomorrow.

Click to expand...

That ought to do it. If you look at the splined shaft you can see that the splines on the non-driven end of the shaft are all flattened out and the spines on the driven end of the shaft are nice and sharp. Obviously the shaft was pressed into the armature stack from the non-driven end. I would still be mightily surprised despite it being an interference fit, that those splines slipped inside the armature stack. The armature stack isn't as important as the stator stack. If...and I'm skeptical that it is slipping...but if it's slipping, then drill a couple of angled holes into the armature stack and into the shaft and then put a screw down in the hole and then fill in the hole around the screw with super glue. Runny/thin glue will naturally flow into and around the screw. The thicker stuff is good for filling gaps, but it doesn't flow so well. The screw is the strength to stop any further slippage. A 6-32 screw has a lot of shear strength, but use a 10-32 0r 5mm screw just to be sure it will hold. The glue secures the screw from slipping or coming loose.

All three phase are melted to bits so i say you might have overloaded it a little bit 8) , looks like the weak spot has been found on the rotor to much torque and it spins the shaft on start up I suppose the smaller rotors slip easier than the larger brother and that temp plays a big part as it was quite cold but like u say it can be sorted if i drill 3 m3 holes in a triangle shape down the sides of the shaft fill it with liquid thread lock and drift a trimed 3.5mm hardened nail in them both ends of the rotor offset in a way to keep it balanced and the shaft locked down for good hopefully.
The design of these motors has amazed me, get a bread loaf magnet, stamp all the parts and make the can to length very simplistic but effective

China seems to be magic smoke capital of the world their fireworks display team seem to have gone the whole nine yards in sabotaging every product of their own to be as shit as possible in an attempt to make sure we all get to see big displays as often as possible and credit where its due they really got making a shitty product down to an art now I've seen many of their product put out a cracking display for the whole family to gather round and see, FLASH BANG magic smoke lmao.

IBM have got refils for that boma if your interested

Ianhill said:

All three phase are melted to bits so i say you might have overloaded it a little bit 8) , looks like the weak spot has been found on the rotor to much torque and it spins the shaft on start up I suppose the smaller rotors slip easier than the larger brother and that temp plays a big part as it was quite cold but like u say it can be sorted if i drill 3 m3 holes in a triangle shape down the sides of the shaft fill it with liquid thread lock and drift a trimed 3.5mm hardened nail in them both ends of the rotor offset in a way to keep it balanced and the shaft locked down for good hopefully.
The design of these motors has amazed me, get a bread loaf magnet, stamp all the parts and make the can to length very simplistic but effective

China seems to be magic smoke capital of the world their fireworks display team seem to have gone the whole nine yards in sabotaging every product of their own to be as shit as possible in an attempt to make sure we all get to see big displays as often as possible and credit where its due they really got making a shitty product down to an art now I've seen many of their product put out a cracking display for the whole family to gather round and see, FLASH BANG magic smoke lmao.

IBM have got refils for that boma if your interested

Click to expand...

I wonder if expensive IBM magic smoke is compatible with cheap Chinese magic smoke?

THat's my 2000 watt boma. It was running fine and I was maxed out at 150-160F. All of a sudden the motor stuttered a couple of times and smoke was poring out the vent covers. I walked the rest of the way home. When I got home I pulled off the motor and found those vent covers were completely clogged up. What happened is the cottonwood trees around here were in bloom so fluffy little seeds were everywhere on the road. I must have been stirring them up off the road and sucking them into the motor. Since the driven side of the motor still had the vent grills in place, the seeds collected on them and blocked all air flow. After that it was just a matter of minutes between running hot and safe and melt down. Also, it didn't help that I had phase current limiting turned off.

China does make lots of really cheap crap and every now and then some good stuff. For example Xiaomi is the Chinese version of Samsung. Their products are every bit as good as Samsung or Sony.

Scooter took an hammering today, rain, mud, bumpy roads nothing could stop it.
I've decided most of my riding is off road and uphill so having such a high top speed is not really useful when I'm no where near it most of the time, so I'm going to gear up from 5-1 to 6.7-1 to give me a bit more range when climbing and torque not that im short on it.

I'm going to trim the handle bars stem down 40mm too it's wearing the bearings faster leveraging my weight and it's too high for throwing it around keeps wanting to wheelie and I'm in the wrong position to tame it.

So 2 more cheap upgrades hopefully to make this thing climb like cliff hanger and help me keep a grip of it while doing so.

My motor started playing up turns out the hall sensor was dodgy after testing and the drive sprocket had backed off with all the hot and cold cycles. I also noticed the rear brake hydraulic hose that passes over the motor will be in contact with alot of heat I've not had any trouble yet but I will get a bit of thermal barrier sleeving and run the pipe through that for added piece of mind.
The spare motor I have to replace the stock original has the same ratings but is 1cm longer, weighs 0.5kg more and has 4mm phase wires stock instead of 2.5mm so I'm looking forward to see how the performance changes. It was a squeeze to get the can in place with the larger wires and the extra 1cm length I had to use alot of muscle to get it all in place and get the wire to clear the suspension spring, I will add extra support on the rear of the can with some fixings I think to take the extra ooomph.
I won't bother rewinding the stock motor now I now it's smaller than my new unit I may just offer it as spares to someone that wants it as it still runs a treat drop a new Hall in and it's good to go just had new bearings to few months ago if anyone is interested in a dirt cheap motor give me a shout.

Covered the hydraulic hose over the motor with bubble wrap then foil then duct tape so the rear hose is protected as it travels over the motor in a vunrable heat area.
My new motors sprocket sits closer to the housing by a few mm putting the chain line out, but after flipping the wheel swapping the disc to the sprocket side I found the wheel lined up better than before and with a few tweeks to the brakes it's all back together spinning free, half of the wiring has been tackled with my large soldering iron a hour or so with my small iron tomorrow and it should be back working all cleaned up and running better than ever.

I'll put a video up soon of the scooter after its upgrades one showing its new speed and the other with a walk around what I've done, It's flying now I'm pulling 45mph up hill with less than half batt, i could only get 46mph on the flat before its gonna crack the 50mph mark when I charge it and do a speed run on the flat no doubt about it and it only weighs 35kg lift it over fences easy etc very versatile.

This new motor has a larger can and rotor by 1cm in Length but has a higher kv so it equates to more speed and power but the same current handling so I will have to keep an eye on temps in burst mode for long durstions but today I give it the death for around a mile and it was barely warm at all the whole system was mildly warm at best I've put 5.5mm bullets now on the phase wires and kept the 4mm bullets in the xt90 on the battery got all the power wires short as can be and close together as possible my whole power run is only 40cm from batt to comtroller to motor so the 12awg I got is more than enough to carry the juice, and ive soldered up a bit of the shunt on the sunwin so I will have to report back on what amps im getting and where but it's called the black widow originally by the makers and it stands upto it's name now I've had a tinker.

It's running 75amps on medium now no heat issues so far and the new motor is going faster the kv seems a little higher than the previous motor but due to the In crease in rotor size there's more torque available I was concerned if it would rev as high as my smaller motor being more rotating weight etc but the performance is sweet I couldn't look down when I was in turbo mode it was to hectic it's got to be over 5kw now I'd imagine, only problem my new fancy wheel tensioners started slipping half way through the run theres a ton more torque now and it spoiled my fun.

Pictures of inside the battery box showing the secret sauce, the key here is the battery cable run to control to motor and through the shunt is all short as possible, I could improve the battery a little as it's two separate 8s packs that I pair so that adds length that could be got rid of and charge from bms at a later date but for now it's staying as is and getting somemore miles under its belt.
Got new tyres to fit on they are labeled the same size but I think China has had its fingers in the pie here ae they are slightly wider than the old ones but they will clear no problems. After fitting the new motor and having a general service and a tidy up its staying as is for the foreseeable future as I've got the a2b metro in the background to play with now and that slowly got its parts list coming In so ive got to work some magic over that now with moped rims and tyres custom pretty much everything.
View attachment 1

Got some tyres that were out of round and generally dangourous crap so little video of what I did to them still got one left too.
[youtube]rlCweZnvE68[/youtube]

Ianhill said:

Got some tyres that were out of round and generally dangourous crap so little video of what I did to them still got one left too.
[youtube]rlCweZnvE68[/youtube]

Click to expand...

Well it's round now!

This is up for sale in the uk if anyone is interested PM me.

OOOH! I want it! LOL.

Post in the for sale section.