"Direct Drive to Diff" MT2 18SS

[GO-RIDE.com]

MetalMan, that is a really cool project. Thanks for sharing the build. Is there a smaller outrunner motor that would work good with a MambaMax and fit in a CRT.5? I really like my CRT.5, but I wish it was lighter and had more room on the chassis for batts. Does removing the center diff make driving on a track a lot harder? Is the direct drive system more for bashing?

Thanks again!

[MetalMan]

Originally Posted by GO-RIDE.com

MetalMan, that is a really cool project. Thanks for sharing the build. Is there a smaller outrunner motor that would work good with a MambaMax and fit in a CRT.5? I really like my CRT.5, but I wish it was lighter and had more room on the chassis for batts. Does removing the center diff make driving on a track a lot harder? Is the direct drive system more for bashing?

Thanks again!

I'm sure there is a smaller outrunner that would work just fine. In his Redcat 1/10 4wd truck lincpimp is using a 2826, which is a bit smaller than mine. You'll want a motor with a kv of ~900 if you use 4s Lipo and 3.5" tire to achieve 40mph. The Mamba Max might have difficulty starting the outrunner with its current software, but the future software release (if it ever comes out) should fix that.

I honestly couldn't say if this setup is good for bashing. Bashing can put a lot of strain on drivetrain parts as it is, and if you remove the center diff and not have a slipper clutch with an outrunner setup, you'll put even more strain on the drivetrain components.

As for driving with this setup on a track compared to a center diff, I have absolutely no idea. We can make guesses, but no one has tried a "direct drive to diff" outrunner setup on the track so far, and certainly no one has compared it to an inrunner/center diff setup.


Well, I have good news. I took apart the MT2 diffs and found no metal shavings in either the diff housing or the diff cup. There was, however, a wheel nut that loosened while driving last night, which caused one of the wheel to get stripped at the hex (the MT2 has metal drive hexes). That was the problem that I thought was the rear diff.

[sikeston34m]

I'm glad you found it wasn't any worse than that.

[lincpimp]

I really think that the direct to diff outrunner setup could do with some sort of slipper arrangement. I was thinking to use a revo slipper on each end of the motor. Where the spur is normally mounted, a plate with standoffs and some sort of adapter to mount a drive cup could be substituted. This would require shorted center driveshafts. Not sure if this would be feasible, but it is all I can come up with.

Here is an idea that will really annoy the electric diehards!!!

Why not make the center shaft of the outrunner capable of mounting a nitro clutch on either end? That would create a mechanical disconnet, and cure the startup cogging problem. Mechanical brakes would also have to be employed though, raising the complexity a notch.

Plus I have no idea how big the diameter the nose of a nito engine crank is. It would have to be smaller than 5mm to allow the shaft to plass thru the bearing, etc, in the outrunner. Bigger outrunners use the 6mm shaft, so maybe it would work.

I only throw this idea out cause the cluch adapter on my revo really makes the motor work smoothly. I have no idea if the nitro cluch would be strong enough to handle the power and torque of the outrunner.

[sikeston34m]

Hey Linc,

The clutch is an idea if you can come up with the mechanical aspects of it. Design I mean. It's a tradeoff since you have to use mechanical brakes though. Just remember, down on the center driveshaft there is MUCH higher torque and higher gearing.

Hey Metalman,

LOL@Crow screaming. That's gotta be strange.

I've never tried an outrunner on 10S A123. I have tried an E maxx Outrunner setup on 6S2P A123 which resulted in stripping the hole in the tranny drive dog. I wasn't jumping or anything. It was from HARD acceleration with a 715kv 3530 5 turn.

Sounds like High Timing works good on that setup.

Can you get us a video of this thing?