Upcoming Castle Outrunner Motors

[sikeston34m]

Originally Posted by lincpimp

Sikeston 34m has done this with his emaxx. went from a 2826 axi with 22/40 (something like that) gearing to a medusa...

I will say that 99% of people will find an inrunner preferable over an out runner in a land vehicle.

Yes, this is true. There isn't a specific comparison thread about it, ya gotta read between the threads. LOL

Or just ask.

Both setups use 5000mah 20C 4S Lipo

AXI 2826/8 geared 22/40 - Great little setup. I would have to say the MOST efficient setup I have ran. Usually about 10 extra minutes of runtime than an inrunner setup. This motor will run higher gearing, but temps get "uncomfortable".

Medusa 36-60-2000kv geared 52/18 - Another Great setup. Medusa makes the best inrunners I have ever owned.

It would have been easier to compare the two if I were using an older style feigao 2 pole motor. The gap on efficiency and operating temps would have been large.

When Medusa made this line of motors, they did alot of things right. The 4 pole design is truly superior to the old 2 pole motors. I love my Medusa. A little less runtime than the outrunner, but it makes good power. This setup continues to break driveshafts.

On the other hand, the AXI setup would dominate on short track.

Mike's speed calculator shows these two setup like this:

AXI geared for 30.15 mph
Medusa geared for 33.59mph

I GPSed the Medusa setup at 38mph, so these the calculators figures are a little low.

The AXI setup tops out ALOT faster than the Medusa setup. It's quicker "out of the hole". It will yank the front end right at startup, where as the medusa comes into it's real power a little farther off the starting line.

"when sik said "A super low kv inrunner would make ALOT more torque" I thought he mean than an equivalent size/kv outrunner. Now I think I may have misinterpreted his response."

Sorry, I should have said "A super low kv inrunner would make ALOT more torque than it did before." Not to be interpreted that it would make more than the outrunner.

[sikeston34m]

Ok, here's a showcase for you guys. Maybe you will see why I'm excited about Castle's new outrunner line.

First up is where it all began for me and outrunners. The E maxx with an outrunner directly connected to the transmission input shaft. Actually the motor shaft and the input shaft are the same.



Next up, is the Revo Direct Drive to Diff Build. Powered by a custom wound AXI 4130. It kept blowing the bearings on the RCM diffs in about 2 runs. The Ceramic Nitride bearings faired no better. Differential toughness is gonna have to catch up before this setup really works well. Show me an inrunner that explodes diffs like this.

http://www.youtube.com/watch?v=dFDrYXLkcGg

Next up is the AXI 2826/8 setup.

[sikeston34m]

Let's talk about why outrunners have more torque.

A Medusa 36-60's armature is 15mm in diameter and is 35mm long. It has 4 VERY strong magnets, thus making it a 4 pole motor.

An AXI 2826's stator size is 28mm in diameter and is 26mm long. The ID of the magnets inside the rotating endbell is 29mm.

The larger diameter is "easier" to turn because of leverage. This is why there's a knob on the door instead of just a shaft sticking out. LOL

Take a look at my avatar. For each phase shift, there are 4 teeth of the stator energized at any given time.

This means, at any given time, there are 4 magnets in use at any given time. More Magnets, greater force.