the death of an ebike

[auraslip]

I posted about my cracked axle a couple months ago. Well, after 2,000 miles it finally gave. Luckily right when I got to my girlfriends house. I popped up a curb and heard a pop. Slid to a stop. Got off my bike throttle makes the wheel twitch. Bike shoots 3 feet up in the air when it clicks into motion again. Then BOOM SPARKS at the axle. And nothing. Quite a show for my girlfriends friends.

Anyways - I really hope I didn't bust my controller because all of the phase wires were shredded and some of the hall wires.




If you drill out your axle make DAMN SURE the bit is straight.

BTW, anyone want a 9*7 9c motor? In good shape. No refunds though

[Miles]

I think you should change the title to "death of an ebike".........

[dogman]

Holy moly, I thought you'd junked that motor.

[boppinbob]

Yes change to"Death of an ebike". After what happened to Pure I'm jumpy when I read "death" in a title.

[motomech]

ouch!

[Pure]

I didn't die Bob. lol

Yeah, I'd say that motor has seen better days. Can't axles be replaced, or is it worth the trouble on a cheap(ish) 9c?

[auraslip]

I didn't junk it! I was too broke to get another one! I was thinking the generous clamping torque plates would prevent this from happening... some other members gave me the same advice. Also, the rear wheel was still firmly in the frame. The wheel was just rubbing the chainstays. That would be another +1 for clamping dropouts. If the axle ever breaks, the motor will stay attached to the bike!


I think someone with a giant industrial press can get the axle out. It actually might be worth someones time since this motor is so modded out. Good ventilation job on the covers, new USA made bearings, temp sensor on the windings. I put 5kw peaks into daily, and cruised at 3kw for around 10 miles before it'd over heat. Could be brought back to life if someone has a motor with burned out windings and can do the axle swap.
I'm willing to sell the motor for whatever someone thinks it's worth to them.


Love these guy's vidoes!

[dogman]

Ahh, better title.

Shocked it lasted that long.

[auraslip]

didn't realize people were so jumpy - apologies!

I was hoping this would turn into an awesome "how I killed my ebike in a dramatic fashion" photo thread

[Lessss]

I popped up a curb

... so you deliberately killed it.

[Pure]

e-bike homicide

[neptronix]

WOW, that axle is hollow! I am surprised it did not die sooner. Did you bore that axle out, or is that stock?

This is why i was nervous about grinding away at my magic pie axle to shoehorn 4 wires into it.

[neptronix]

p.s. Auraslip, it is high time that you and me joined the m.e.n.s club.

[boppinbob]

I didn't die Bob. lol

I bet they gave you some kick ass opiate painkillers though.

[amberwolf]

BTW, anyone want a 9*7 9c motor? In good shape. No refunds though

What do you want for it? I bet I could deal with the axle problem one way or another....

Did you bore that axle out, or is that stock?

It is bored out, but the drill didn't go in quite straight, and that's most likely what caused the problem in the first place. I forget which thread his wire upgrade is in, but it shows that, plus the original beginning of cracking of the axle.

I was hoping this would turn into an awesome "how I killed my ebike in a dramatic fashion" photo thread

I could post the pics of how I helped grind up the inside face of my Fusin covers with a hose clamp, and coated the entire motor inside (including the nylon gears) with aluminum shavings....

Turns out to have been easier to fix the Fusins that Dogmain cooked in his meltoff than it has been to fix that one!








Hose clamp is there becuase of this little crack:

keeping the clutch from gripping....


Plus, I overheated the motor so much after the 15+ mile ride home at slower-than-usual speeds (to keep the clutch from slipping) that I couldn't touch it, and the halls stopped responding, so the last half mile was pedal-only.
viewtopic.php?p=550415#p550415


There are some fairly dramatic destruction pics of chain drive failures on CrazyBike2 from a while ago, which I can post here, if this is the kind of hting you want in this thread.

[auraslip]

That's pretty gruesome amberwolf.

In other news, it looks like I blew up the mosfets on my controller. When the green phase is hooked up to a new motor, it is hard to turn just like a phase short. No fun.

Will this be a simple mosfet swap, or will there be something more too it? Anything else that could of blown up?

[Doctorbass]

I posted about my cracked axle a couple months ago. Well, after 2,000 miles it finally gave. Luckily right when I got to my girlfriends house. I popped up a curb and heard a pop. Slid to a stop. Got off my bike throttle makes the wheel twitch. Bike shoots 3 feet up in the air when it clicks into motion again. Then BOOM SPARKS at the axle. And nothing. Quite a show for my girlfriends friends.

Anyways - I really hope I didn't bust my controller because all of the phase wires were shredded and some of the hall wires.




If you drill out your axle make DAMN SURE the bit is straight.

BTW, anyone want a 9*7 9c motor? In good shape. No refunds though

I can see in one of your picture thatyour axel have some rust directly where it broke... maybe it already had some crack or fatigue and thanbroke completly?

it is rare that people thighten their axel nut with the right torque.. did you used a torque wrench?

When people torque their axel by the "feeling" often they already go over the plastic state of the metal and it's too late.

Doc

[auraslip]

thanks for the reply doc bass

To answer your question, these were clamping dropouts I made myself. Which is very good because the wheel stayed in the dropout after the axle broke.

The axle was original cracked after I drilled it out to make more room for fatter wires. I wasn't precise enough with my POS drill and it went at an angle. Possibly I also clamped down too hard.

[amberwolf]

That's pretty gruesome amberwolf.

Yeah, it looks worse than it is, though--just cleaned it all up today. Pics later, but description of getting it done in this post:
viewtopic.php?p=576368#p576368
Still gotta repair the cracked clutch, if I can...but one tooth is broken off a gear, so it's a good thing I have the others from Dogman already.

Will this be a simple mosfet swap, or will there be something more too it? Anything else that could of blown up?

Gate resistors or driver transistors, sometimes.


Decide what to do with the motor yet?
EDIT: Nevermind that last question; I saw your new thread (PM'd you, too).

[auraslip]

Ok - tech question

The ground and positive side of the green phase was shorted. Removed a single mosfet that looks funny. Now it's no longer shorted. Mosfet was shorted. WELL THAT WAS EASY.

OK, but mouser has two irf4110 and I don't know which one to get.

http://www.mouser.com/ProductDetail/Int ... xA51Xu4%3d
http://www.mouser.com/ProductDetail/Int ... MzyMeP0%3d

???

Praying it's not the gate resistors and driver transistors too because I'm sure that wouldn't be fun to diagnose.

Also, I got some temp sensors. I'm gonna have one for the motor, and one for the controller. They lm25 IIRC. Anyone have anythoughts on where I should epoxy them? Like what fets will get the hottest?

[amberwolf]

OK, but mouser has two irf4110 and I don't know which one to get.

http://www.mouser.com/ProductDetail/Int ... xA51Xu4%3d
http://www.mouser.com/ProductDetail/Int ... MzyMeP0%3d

the G part is "Lead Free Halogen Free". Otherwise they're identical, AFAICS.
https://ec.irf.com/v6/en/US/adirect/ir? ... RFB4110PBF
https://ec.irf.com/v6/en/US/adirect/ir? ... FB4110GPBF

Praying it's not the gate resistors and driver transistors too because I'm sure that wouldn't be fun to diagnose.

Relatively easy to diagnose, but since theyr'e SMT parts, harder to fix. I have one here I suspect that is the problem, but haven't fixed yet cuz my bad eyes and shaky hands.

Also, I got some temp sensors. I'm gonna have one for the motor, and one for the controller. They lm25 IIRC. Anyone have anythoughts on where I should epoxy them? Like what fets will get the hottest?

[/quote]
Theoretically they should all be the same temperature, but whatever is closest to another component that either generates it's own heat (like caps, resistors) or reflects the FETs' heat back to it, will get hotter, and so will FETs that are less-well heatsinked. Probably the closer to the middle they are, the hotter they'll get, but you'd have to empirically test that to be sure.

[dfar]

gate resistors and driver transistors

Relatively easy to diagnose, but since theyr'e SMT parts, harder to fix. I have one here I suspect that is the problem, but haven't fixed yet cuz my bad eyes and shaky hands.

could you elaborate on how to diagnose or link to an applicable thread showing how please

thanks

[amberwolf]

I don't have a link; you would need to search thru various controller repair threads (unless someone has linked it in the ES wiki http://endless-sphere.com/w ).

However, all you need to test is the resistance of the gate resistors, once you trace down which ones those are on your particular controller. If they are open or shorted (probably open if they did fail) then that should be distinctly different readings from the ones on the other phases that haven't failed.

Then test the gate transistors (again, you'll have to trace down which ones those are). There are numerous articles on the web about testing various transistors in-circuit, if you arent' sure how, either while powered on or without power applied.

Any simple multimeter can do the testing needed.

I'd post more specific directions on how to do ti, but I am very time-limited. (but if you find the links, and articles on how to do it, you could help future people asking the same thing by placing the information into the ES wiki. )

[auraslip]

well, I installed a new fet.... hooked up my test setup....

and nothing worked.

removed the fet... and it's shorted again.

WTF, did I get it too hot?

[auraslip]

EDIT: I must of gotten it too hot. New fet in and motor spins great.