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teddillard
17 December 2011, 0529
I'm posting this right now to keep myself honest. Also because I can't actually do any work right now, since I'm waiting on parts. :O

I started out with a Motenergy ME0709 running at 74V. It did wheelies. I then got one of the Manta motors, and it didn't do wheelies anymore, but it started pulling like a bitch starting around 30mph, and calculates out to over 100mph. Like an idiot, I sold the ME0709 before I got good tires mounted, so I couldn't do any testing.

Then, the Manta started binding up against one side of the case, against the magnet. So I tore it down... down to little bitty pieces (in the process, I broke a 12-ton shop press and learned a whole bunch of stuff about where these motors came from that I unfortunately can't dish publicly, though I'm trying to figure out a way to tell at least some of the story without needing a lawyer. I also learned a whole lot more about the legacy of the ETEK motor, Cedric Lynch and tales of industrial development, innovation, heartbreak and dreams. I want to put that story together too, but it's touchy, as you can imagine.

I also, for the record, learned how to tear the motor down without breaking a 12-ton press.*

Right now, the Manta is down to the very smallest bits, and I'm going to measure it up before I put it back together, so someone could do a CAD drawing of it if the spirit moves. Then I'm going to go through the process of re-assembling it. The armature literally gets glued to the shaft, if you can imagine that, positioned with mica shim stock. I'm intending to publish measurements for checking out motors (without tearing them down) so you can tell what kind of shape the thing is in, hopefully before you buy it. I also want to do a side-by-side comparison of the authentic Briggs and Stratten ETEK and the Manta.

In any case, I'm picking up another ETEK, (this one will be a B&S, not a Manta), a Motenergy ME0709, and, possibly the new Motenergy ME1003, and intending to do some serious comparison tests... with data even. :)

There, I said it. Now there's no backing out. :D

Some more detailed information can be found on my blog, here:
http://evmc2.wordpress.com/category/the-etek-thread/

...but here's where it started- the under-10-minute ETEK (Manta) teardown:

<iframe width="640" height="360" src="http://www.youtube.com/embed/gqluuuXTqpU" frameborder="0" allowfullscreen></iframe>

*...in spite of this, remotecontact still won't let me touch his motors anymore. :cool:

teddillard
17 December 2011, 1559
(Manta motor) Polished up the parts and measured them up today and put together a scale drawing in Photoshop. Here's a little animation of how the collars fit on the shaft to hold the armature:

<iframe width="640" height="360" src="http://www.youtube.com/embed/18uEOaS5WGM" frameborder="0" allowfullscreen></iframe>

The armature is assembled off the shaft, then the right side collar is held in place with a nut (not shown). Then the main collar is a pressed onto the shaft from the left side.

ZoomSmith
17 December 2011, 1623
Tull.
Nice.

Athlon
18 December 2011, 0426
BTW in a few month i will be able to add some info about some special brushes for Agni to be used in critical condition when regular brushes fail and burn down

teddillard
18 December 2011, 0513
Sweet! Just updated the video... added the rotor and sequenced it to show how it goes together. (...more Tull)

billmi
18 December 2011, 0909
Nicely done, Ted.

liveforphysics
21 December 2011, 1740
I can't keep those motors alive for 5 minutes before I melt down the brush carrier.

But there is a fix, on your brush carrier, externally run some leads, at least 2awg with a ring terminal on the ends to each of the 4 positive brush holders with that ring terminal pinching directly to the little forked lead coming off the brush, make sure each current carrying surface is lapped flat, and clamp it down. You end up with 8 leads leaving your motor, 4 positive and 4 negative. Trim each one to equal length and bolt the bundle to your controller's output lugs.

Now you're not using that awful series distribution to the brush carrier setup that gets to 200degC while laying in that groove on your brush holder after 3 minutes of riding. Your motor will run cool enough that it shifts the failure mode form the brush carrier to the rotor's solder melting and slinging itself apart, which can take as much as 10minutes of riding to do.

You're welcome. :-)

teddillard
22 December 2011, 0259
I can't keep those motors alive for 5 minutes before I melt down the brush carrier.

I know, I've heard about how you get. :D



But there is a fix, on your brush carrier, externally run some leads, at least 2awg with a ring terminal on the ends to each of the 4 positive brush holders with that ring terminal pinching directly to the little forked lead coming off the brush, make sure each current carrying surface is lapped flat, and clamp it down. You end up with 8 leads leaving your motor, 4 positive and 4 negative. Trim each one to equal length and bolt the bundle to your controller's output lugs.

Sweet.



Now you're not using that awful series distribution to the brush carrier setup that gets to 200degC while laying in that groove on your brush holder after 3 minutes of riding. Your motor will run cool enough that it shifts the failure mode form the brush carrier to the rotor's solder melting and slinging itself apart, which can take as much as 10minutes of riding to do.

10 minutes is all I need. :O But I'm looking into mist injection for both sides of the rotor to forestall that event for a few more minutes.

Thanks!



You're welcome. :-)

teddillard
11 January 2012, 0404
"Part # ME1003"

https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/398416_3116939641955_1218396040_33456365_858938308 _n.jpg

...let the Games begin! :D

Allen_okc
11 January 2012, 0713
that looks like my next motor...

dice23
11 January 2012, 0733
to small! lmao...more power!

Allen_okc
11 January 2012, 0759
but im sqeerd Jeff, anything over 35mph freaks me out...

teddillard
11 January 2012, 0853
but im sqeerd Jeff, anything over 35mph freaks me out...

(psssst. I think your "1" key isn't working yo...)

:D

Allen_okc
11 January 2012, 0953
your right Ted, well almost, i meant to push the number 2 key...

Thank You for correcting that type-o...

:cool: im still drinking coffee and smoking a cigarette at 135mph...