5305 @ 215 degree C (420 F)

methods

methods

1 GW
Joined
Aug 8, 2008
Messages
5,555
Location
Santa Cruz CA
Once again I am doing research for you guys. :roll:

So I was practicing wheelies up and down the street dragging my feet and taking off over and over and over.
After about 15 minutes the motor picked up an odd sound
About 2 minutes later I started hearing a grinding sound with a noticeable lack of power

It was not until then that it occurred to me that I was lugging the motor and applying 120A over and over again. :?

I had the current limit set to 110A (motor current) and battery voltage was around 88V
I did not have the temperature protection hooked up...

Even with the controller powered off the motor now drags like it has the regen brakes on.
I checked the temp with my multimeter and although it was off the chart I interpolated out to about 420F give or take 15 degrees.

I am letting it cool now.
The last time I gave it the gas went. . .

I am thinking that maybe somewhere in the middle the phase wires shorted
Just enough to cause electrical braking but not so much as to disable electrical drive.

We will see

-retard
 
Could be you just melted the leads together shorting the motor. I did it 3 times when I was abusing my 5302 with a 100 amps

Mark
 
Thats pretty warm, was this on the Zippy packs ? If the zippys are ok with you, they must be outstanding, as you really push the gear through the limit. Thats cooking temp!!
 
Sorry to hear about that.

At 200+ degrees you may have done some damage to the magnets.

It would depend on what grade/type of magnets are in the X5. More info about what temps magnets fry at is here

http://www.kjmagnetics.com/specs.asp

Anyone know what grade magnets the X5 uses?
 
So I let it cool down a little and tested it.
The hall sensors are fine
The motor runs but just draws a ton of current

Free-wheel at about 15mph takes 15A

Turning the motor by hand creates a ton of resistance.

I am going to be optimistic and go with Marks idea that I may have just shorted out the phase wires.
I will go in and do a little test.

Amazing that the Hall sensors still work eh?
Those things are quality.

The magnets? It would not surprise me if they were jelly.

Zippy packs? This was actually the 9Ah pack and it was not even warm.


-methods
 
You should probably also check the glue used for the hall sensors. It's not the problem here of course but when you get the phase wires fixed, you should check that before doing normal riding again.
 
Oh.. I just hope you did not reached the REAL ELECTRICAL LIMIT OF THIS MOTOR!.. there are only few member here that had burned their motor.. I mean cooked!

215 degree C is 35 degree OVER the max temp class of winding for motor!! the H class...

melted varnish on the wires would really be a bad new!

Good luck to repair it Methods!

Doc
 
Also plenty hot enough to cause the magnet epoxy to liquify. I bet it's pretty toasted. Next time I have the cover off my motor I'm putting in a sensor to a remote thermometer. We are riding around like we have cars with no hot engine light.
 
Last summer i added a temp sensor (from a BBQ digital thermometer)

it work really nice! I can set an alarm temp that indicate me to slow down a bit :wink:

Monitoring every stressed parts of the ebike is comething i would call : Necessary when playing with 5kW + :wink:

Doc
 
Disconnect the motor from the controller and see if you still feel resistance to turning.

If there is still resistance / cogging, then you probably have shorted phase wires.
If the resistance goes away, then your controller is blown.
 
Yea, I had the temperature sensor in there.
I was just not monitoring it.

I opened up the motor.
First thing I noticed were solder balls here and there
Got hot enough to melt the solder right off the board where the windings meet the teflon cables

I removed the board and separated out all the windings.

They are fubar.
For lack of a better way to describe it,

A-B 1.4Kohm
B-C short
A-C short

Of course I separated the point where all three windings meet for this measurement.

All those measurements should be open circuit.

Now the question is whether I want to try to re-wind it or just go over to a 2WD setup.
I dont want another 5305. It cant put out enough power for me.
2 5305's would be too heavy

What pair of motors would be comparable in weight and power to a single 5305?

Any suggestions on how to mount a motor in an aluminium front fork that takes a 20mm round axle?

-methods.
 
methods said:
I want to try to re-wind it or just go over to a 2WD setup.
I dont want another 5305. It cant put out enough power for me.
2 5305's would be too heavy

What pair of motors would be comparable in weight and power to a single 5305?

Any suggestions on how to mount a motor in an aluminium front fork that takes a 20mm round axle?

-methods.
Click to expand...

Why not two BMC 1000W .. or Etek.. or mars motor ?? :twisted:

Can you just take close pics of your roasted 5305.. i would keep that for my archive :mrgreen:

Doc
 
I will download the pictures later.

I will have to go with Etek or mars.
The BMC motors are too expensive. For 2 I will end up spending $1k, I will need 2 controllers, and what about all that unsprung mass. . .

Ok... I have paid no attention to the other chain drive options till now.
If I go with Etek or mars I will have to custom fab everything (..sigh..)
I hate metal fabrication, especially aluminum.

Ok... Ok... Here we go with another endless learning curve

I guess I will just start looking at what the motorcycle guys are doing.
If I take one of their power setups and put it on a bike I should have them beat with my power to weight ratio. :?

-methods
 
Why not do what Liveforphysics is doing with the dual RC motors to put out 18kw in about a 60lb package, bike batts and everything? Skip the bearing upgrade at first and it's fairly economical. If 10-15lbs more and the space it requires is of no concern, then of course go for the Mars or Etek solutions, since you stay in proven territory. All of us budget minded performance cravers want to see you pull it off with tremendous success, so we can follow in your footsteps.

Best of luck whatever route you take!

John
 
The quick way to home in on the limit of equipment is to look at the racers. And even then their equipment is only expected to last for a finite number of races.

Sounds like your next build will be very interesting.
 
John in CR said:
Why not do what Liveforphysics is doing with the dual RC motors...
John
Click to expand...

Trouble is that I am a mechanical retard.
All of my tooling, all of my experience, all of my passion is geared toward electronics.

I went through a phase of my life where I was building Honda's but truth be told, nearly everything I ever worked with was bolt on to some degree.
I can weld, I have no fear of complex systems (i.e. I can disassemble and reassemble an engine), and I can do basic fab with a drill and an angle grinder but I just dont have the intuitive feel for mechanical systems. My instincts drive me toward hose clamps, zip ties, expanding foam, angle grinders, spray paint, and "kits".

I know, shameful. :oops:

-methods
 
methods said:
John in CR said:
Why not do what Liveforphysics is doing with the dual RC motors...
John
Click to expand...

Trouble is that I am a mechanical retard.
All of my tooling, all of my experience, all of my passion is geared toward electronics.

I went through a phase of my life where I was building Honda's but truth be told, nearly everything I ever worked with was bolt on to some degree.
I can weld, I have no fear of complex systems (i.e. I can disassemble and reassemble an engine), and I can do basic fab with a drill and an angle grinder but I just dont have the intuitive feel for mechanical systems. My instincts drive me toward hose clamps, zip ties, expanding foam, angle grinders, spray paint, and "kits".

I know, shameful. :oops:

-methods
Click to expand...

I'd suggest something like an etek then too. Means you can skip the complexity of getting and mounting a gear reduction drive. There's the Mars brushless (etek bolt on replacement), would it work on the kelly controller you have? I'm not sure...

see here: http://www.evalbum.com/1511

You could even bolt it on like he did...on your Kona to skip suspension chain growth complexities....and keep it ghetto :twisted:

However, here's a question: What do you aim to accomplish with a re-build?
 
for sale here and more info http://www.teamdelta.com/products/prod5c.htm
(plus mounting plates etc, keep scrolling down)
Here are the specifications:

Torque constant = 1.2 in-lbs/amp

Voltage constant = 70 RPM/volt

100A continuous, 200A/1 minute, 300A/30 seconds

6 HP continuous, 15 HP peak

88% efficient

24-36V design voltage, 48V absolute max

20 turn, fitted with hall effect sensors (+12V powered)

10 milliohm phase resistance

Stepped output shaft, 2.4" long:
0.750" dia. by 1.0" long with 3/16" keyway
1.170" dia. by 1.4" long

Same mounting format as the brushed Etek

Weight: 22 lbs. (shipping weight 24 lbs.)
 
I am sold on the Etec power, you certainly dont have to convince me of that.
I think a 44.4V 12S lipo would be perfect.
My current 88.8V 9Ah would convert down to a 44.4V 18Ah in about 17 nanoseconds

I see that they sell mounting brackets too which would be a big help.

I guess I will have to switch to a steel frame if I want to go Etec.
Welding to a steel frame is not a problem for me.
Mounting to an aluminum frame would be real lame.

I guess I could finally get that aluminum conversion kit for my Mig

Point me to some threads where people have mounted these things.
I started looking through the non-hub section but you know how it is. . .
Like digging through a corn field looking for a baseball bat.

-methods
 
methods said:
I am sold on the Etec power, you certainly dont have to convince me of that.
I think a 44.4V 12S lipo would be perfect.
My current 88.8V 9Ah would convert down to a 44.4V 18Ah in about 17 nanoseconds

I see that they sell mounting brackets too which would be a big help.

I guess I will have to switch to a steel frame if I want to go Etec.
Welding to a steel frame is not a problem for me.
Mounting to an aluminum frame would be real lame.

I guess I could finally get that aluminum conversion kit for my Mig

Point me to some threads where people have mounted these things.
I started looking through the non-hub section but you know how it is. . .
Like digging through a corn field looking for a baseball bat.

-methods
Click to expand...

file.php


Ok, first off, on that swingarm of yours what are the pivot points?

Could you pay someone with skillz to weld a thick aluminum plate to your lower swingarm member on the left side of the bike. Then bolt the mars through, and connect it to a 219# kart sprocket on bolted to a disc brake on the rear wheel hub. Motor then moves with rear suspension but mounting plate is sized to not interfere with swingarm movement when compressing.
file.php
 

Attachments

  • weld_to_lower_swingarm_member_LHS.jpg
    weld_to_lower_swingarm_member_LHS.jpg
    2.2 KB · Views: 5,595
I think we can forget about mounting 22 lbs on ONE SIDE if the swing arm...it will create too much stress on it ant it will break.


If he install it like the Youtube video posted...then it would be balanced and the frame would take it no problem.

To do that. he need a machined custom braket that will clamp to the down tube and secure with the bottle holder hole/screws.

Robin
 
I like that idea. . .

clamp to the down tube
Screw into existing holes

I have many friends at work who could model that in 45 minutes down to every last detail.
We could design it for low cost fabrication, have the gross part machined via CNC from aluminum then I could go in and do the detail work with a drill press to save money

Hmmmm.....

Can I just drive the largest freewheel?
Guess I need to go do some gearing calculations.
I want to go 50MPH at 48V top top top speed.
Maybe I would prefer more torque and less speed so perhaps I will need a custom freewheel.

Ok, this is starting to sound feasible.

How do I deal with the fact that the entire rear assembly moves up and down 7"
Wont that make the chain slack-tight-slack-tight?
Do I just use the derailer to apply tension?
Disable the pedals?

-methods
 
methods said:
How do I deal with the fact that the entire rear assembly moves up and down 7"
Wont that make the chain slack-tight-slack-tight?
Do I just use the derailer to apply tension?


-methods
Click to expand...


It depend on your suspension geometry...in your case I don't think it will move enough to cause any problem.

It won't be heavier than a 5305 Crystalyte...and suspension will react better with almost no weight on the suspension arm.

This sound like a good idea for power!

I have built a electric scooter with a Etek brushed motor..they have CRAZY torque ( http://www.evalbum.com/1535)

Here is a video
http://www.youtube.com/watch?v=qDPPnenI8NI&feature=channel_page
http://www.youtube.com/watch?v=SWHj_-J0ljk&feature=channel_page

It's a little noisy...but when you ride it, you like it!

Robin
 
Nice!

Lipo will make that thing a monster. . .
You will need airbags.

I had no considered the noise factor.
Oh well, this is not my stealth bike.
I was hoping to be able to sneak around in the woods....

What generates most of the noise? The motor or the drive train?

If its the motor, I wonder if the Brushless will be quieter or louder.

-methods
 
You must log in or register to reply here.

Similar threads

jimtmcdaniels
Installing a temperature switch to the outside of a brush DC motor, to avoid overheat damage, any input?
Replies
9
Views
967
jimtmcdaniels
jimtmcdaniels
RustyKipper
    • Like
Ammo box battery with solar charging
Replies
4
Views
719
99t4
9
R
    • Like
A critique of mid-drive riding recommendations (and hub drive criticisms)
Replies
15
Views
5,030
Bullfrog
B
e-beach
‘A Dangerous Combination’: Teenagers’ Accidents Expose E-Bike Risks' A New York Times Article
2 3
Replies
72
Views
5,708
nicobie
nicobie
P
Motor cutting out
Replies
4
Views
1,449
pajtaz
P
Back
Top