Direct Drive to Diff E Revo Build

[sikeston34m]

Originally Posted by lincpimp

I guess that I should do some mods to the old direct-to-diff redcat and see what it can do. Need to find a lower kv motor, most likely a 600-650 would do. That will allow me to put some taller tires on it and it will be more off-rad capable.

The main benefit I found was that there was so muck more room on the flat chassis with out the center diff/trans there. Batteries could be placed on either side of the chassis and the balance was great.

Any ideas on a good out runner with 600-650 kv that would run 5s well and have a 5mm shaft? Here is the info on the motor I am currently using, would like to keep the same diameter if possible:

Specifications:
-Rpm(Kv): 833Rpm/V
-Continuous Currect: 50A
-Max Currect: 70A
-Watt: 980W
-Max Eff: 98%
-Recommended Rotor Prop: 8 x 4 to 15 x 8
-Weight: 150g ( Motor Net Weight )
-Total Length: 78.2mm (include Front and Black Shaft)
-Motor Body Diameter: 37.1mm
-Shaft Diameter: 4.98mm(Front and Back)
-Shaft Length: 15.1mm (Front) and 14.2mm (Back)
-Recommended Input Voltage: 8 - 23 Volt

I went back and read over the "red cat" post and studied the pictures a bit more.

Can you get shorter CVD's for that setup?

I'm with John on his recommendation. The Scorpion 3032 motors would work well also. There are two ways to increase starting torque with a motor change. Increase stator diameter OR increase stator length. All the Scorpion 30xx motors use the 5mm shaft.

[lincpimp]

Originally Posted by sikeston34m

I went back and read over the "red cat" post and studied the pictures a bit more.

Can you get shorter CVD's for that setup?

I'm with John on his recommendation. The Scorpion 3032 motors would work well also. There are two ways to increase starting torque with a motor change. Increase stator diameter OR increase stator length. All the Scorpion 30xx motors use the 5mm shaft.

Thanks for the recomendation. I can always cut and weld my center dog bones to the correct length if needed. A longer stator would be the best bet for this setup as it needs some more torque. Does axi make a similar sized motor to the scorpion 30xx motors? Which scorpion/axi would I want to use? Thanks a bunch for the advise, I have plenty of inrunner experience, but not a wholelot of outrunner testing under my belt!

[sikeston34m]

Originally Posted by lincpimp

Thanks for the recomendation. I can always cut and weld my center dog bones to the correct length if needed. A longer stator would be the best bet for this setup as it needs some more torque. Does axi make a similar sized motor to the scorpion 30xx motors? Which scorpion/axi would I want to use? Thanks a bunch for the advise, I have plenty of inrunner experience, but not a wholelot of outrunner testing under my belt!

What does the Redcat weigh?

This motor looks pretty good for the specs you gave.

http://modelmotors.cz/index.php?page...e=12&line=GOLD

That is AXI's website. They make alot of different size motors.

PS. A little off topic, but was there a special bearing that you used on the 1/8th diff pinions? I know you were having trouble getting them to hold up

[lincpimp]

Thanks Sike, may have to scare one of those motors up. On the weight issue, the redcat is very light, maybe the weight of a rustler sans motor and esc.

I use the std HB bearings that came with the diffs. I had an issue with a stock revo pinion bearing that the race came apart and the balls made their way into the ring and pinion gears. All of my revos run stock diffs at the moment, I was building a killer maxx / racebomb truck and it is currently in a box at work awaiting time and interest from me!