biggest turnigy/turnigy motors right now?

[thedarlington]

so what would happen if we stick a bigger (and hopefully not too expensive) controller to the motor will that work? the question of what benefits putting HAL sensors inside these as many of you guys have done, comes to mind, would that help from blowing it up? hey on the other hand, blowing up motors gives u street cred like throwing flames out the exhaust, cuz ur hardcore like that 8)

 

[olaf-lampe]

so what would happen if we stick a bigger (and hopefully not too expensive) controller to the motor will that work? the question of what benefits putting HAL sensors inside these as many of you guys have done, comes to mind, would that help from blowing it up? hey on the other hand, blowing up motors gives u street cred like throwing flames out the exhaust, cuz ur hardcore like that 8)

Without halls you are more or less limited to 50V . With halls you have the option to use controllers with 72V,100 or even 150V. Pretty easy to kill a motor that way.
If you don't change the voltagerange, a hallsensor-controller only helps to start smoothly from zero rpm. (thats one of the disadvantages of non sensored controllers )
And you don't have to fiddle with servotesters,BESCs and throttle mismatch...

-Olaf

 

[etard]

I saw this motor go on sale on Hobby King today:

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=2129

Other than being really ugly, what's wrong with these motors? Skirt bearing issues?

 

[Jeremy Harris]

Nothing really wrong with that motor. It's relatively low power (maybe 2.5kW or so peak), fairly high Kv at 235, so will need a fairly high ratio reduction drive, but otherwise it's OK, if not ideal for ebike use.

I've been using similar sized outrunners for other purposes and they are fine without skirt bearings. To be honest, I'm far from convinced that skirt bearings are worth having. Being large diameter they are seriously rpm limited and seem to have a fair bit of friction from some reports on here. I've not yet seen hard evidence of a big motor failing from not having a skirt bearing, so can't help but wonder if they are really a solution for a problem that really doesn't exist for a normal ebike.

Jeremy

 

[olaf-lampe]

Nothing really wrong with that motor. It's relatively low power (maybe 2.5kW or so peak), fairly high Kv at 235, so will need a fairly high ratio reduction drive, but otherwise it's OK, if not ideal for ebike use.

I've been using similar sized outrunners for other purposes and they are fine without skirt bearings. To be honest, I'm far from convinced that skirt bearings are worth having. Being large diameter they are seriously rpm limited and seem to have a fair bit of friction from some reports on here. I've not yet seen hard evidence of a big motor failing from not having a skirt bearing, so can't help but wonder if they are really a solution for a problem that really doesn't exist for a normal ebike.

Jeremy

Hi Jeremy,
I can copy that.
My former company who sold long RC-motors with skirt bearings found out, they got hot because there where 3 bearing on one shaft. Which caused a lot of friction because there are always inaccuracies and misalignments. (they called it 'over-engineered')
They added a groove to the outer ring of the skirt and inserted a rubber o-ring where the bell was pressed onto. This way the bell got a better support, but any tolerances were eliminated.

I will try that on my 80-85 I'll get soon. Let's see, what no load current will do.
-Olaf