Direct Drive to Diff E Revo Build

[MetalMan]

Originally Posted by sikeston34m

The MT2 looks like a pretty awesome truck. Are there aftermarket 1/8th diffs available for it also? I'm gonna check that one out a little more. Only weighs 5 pounds! I like that!

In considering other trucks for direct drive conversion, just remember what we've ran into on the cogging issue. I think that line that you can't cross is somewhere about 4 inches of roll out per turn of the motor. Vehicle weight affects this I'm sure.

But more so, I believe it also has to do mainly with the level of EMF pulses that the ESC MUST get from the motor to start properly. More on this later.

The MT2 is pure 1/10 scale, no optional 1/8 diffs. The diffs are actually a weak point on it, even with the optional hardened diffs on the 18SS kit (which are the ones I started with). However, aluminum diff housings have fixed that issue for me, in combination with the hardened diff gears.

My motor is a KMS 4120/06:
http://www.hobbypeople.net/gallery/108521.asp
I get these at a discount 'cuz I work there. It uses a 6mm shaft, so I have a 6mm steel rod that I will turn down to 5mm where the dogbone cups attach.

Only problem that I have found with the MT2 so far, is that the stock chassis is pretty narrow.

[sikeston34m]

Originally Posted by MetalMan

The MT2 is pure 1/10 scale, no optional 1/8 diffs. The diffs are actually a weak point on it, even with the optional hardened diffs on the 18SS kit (which are the ones I started with). However, aluminum diff housings have fixed that issue for me, in combination with the hardened diff gears.

My motor is a KMS 4120/06:
http://www.hobbypeople.net/gallery/108521.asp
I get these at a discount 'cuz I work there. It uses a 6mm shaft, so I have a 6mm steel rod that I will turn down to 5mm where the dogbone cups attach.

Only problem that I have found with the MT2 so far, is that the stock chassis is pretty narrow.

What's the diff gear ratio and the tire height on the MT2?

Hey, that looks VERY much like my motor. Let me give you a word of advice here. When you get the motor, remove the endbell. set it on a table and wick some RED locktight in around the stator and the bear holder. Let it sit for a day or two, then dry up what doesn't soak in. What does soak in, gets hard and creates a VERY secure bond in the absense of oxygen. Some outrunner manufacturers don't loctite both ends of the stator. This can spell for disaster if the stator breaks loose. Check it, it may already be done.

There are some outrunners that have a 5mm shaft that would be suitable, but it looks like you found a great one. I might have to give that one a try.

[MetalMan]

Originally Posted by sikeston34m

What's the diff gear ratio and the tire height on the MT2?

Hey, that looks VERY much like my motor. Let me give you a word of advice here. When you get the motor, remove the endbell. set it on a table and wick some RED locktight in around the stator and the bear holder. Let it sit for a day or two, then dry up what doesn't soak in. What does soak in, gets hard and creates a VERY secure bond in the absense of oxygen. Some outrunner manufacturers don't loctite both ends of the stator. This can spell for disaster if the stator breaks loose. Check it, it may already be done.

There are some outrunners that have a 5mm shaft that would be suitable, but it looks like you found a great one. I might have to give that one a try.

The diff ratio is 38/13 (2.923:1). For now, my tire height is 3.5" (Proline 2.2 Road Rages).

I haven't taken the motor apart yet since this brand uses snap wrings that are difficult to remove. But when I do, I'll put red loctite on it as you mentioned.

[sikeston34m]

Originally Posted by MetalMan

The diff ratio is 38/13 (2.923:1). For now, my tire height is 3.5" (Proline 2.2 Road Rages).

I haven't taken the motor apart yet since this brand uses snap wrings that are difficult to remove. But when I do, I'll put red loctite on it as you mentioned.

3.5 x 3.14 = 10.99 (Tire Radius)

10.99/2.92 = 3.76 inches of roll per motor revolution

This configuration should work! I'm sure you will be able to increase tire size somewhat since it's so lightweight.

The AXI uses those snap rings also. I use a pair of small screw drivers. First pry the ring apart, then starting on one side, pop it up out of the groove. Then using both screw drivers, work all the way around gently prying up until it's completely out of the groove.

I don't think I've ever seen a pair of snap ring pliers that small. I'm sure someone makes them though.

[Matthew_Armeni]

Originally Posted by sikeston34m

3.5 x 3.14 = 10.99 (Tire Radius)

I think you meant circumference

[sikeston34m]

Originally Posted by Matthew_Armeni

I think you meant circumference

You are correct!

Circumference........that's what I meant

Sorry about the Brainfart there. I have those sometimes.

It's been a long day already and I'm wrestling with this truck right now. lol

[Matthew_Armeni]

That's cool, you keep working, I can't wait to see this thing done!