ooohhhh maaaannn!!
as linc would say "hand porn alert"
this new diff ive made to crash's specs....soooooo good!!!
i cant do backflips again! and it handels soooo much better!! can kick the tail out some:yipi:

thanks for the simple design...you know the BB used to center the plastic gear onto the ground down ring gear...well i lost quite a lot of balls from that one when i managed to smash it:lol:
didn't matter though as long as the gear was centered.
filled it with 100k as i like wheelies and sending plenty of power to the rear.

Good stuff. This CD is what I would call the culmination of many ideas from a few people dating back to the first 8th scale CD ever made by CowboyRay. We all came up with something that is easy to make, easy to maintain, rock solid and easy to get parts for. Let's give ourselves a big round of applause. :yipi:

Well said MC.......I agree.....it is a real simple and effective design.....I'm surprised traxxas did try to make a clone of it , kinda like your aluminum clutch disc.....

Yes! I too made a CD usinh MC's designs, and it's been holding up! About 5 monthes now!

I'd love to make two of these for my revos but i lack the tools necessary and being a site work (construction rigging) i work very long hours (up to 70 a week) would realy love to be able to get the power down in my revos they certainly are so torquey it's not funny.

honestly suprised mike hasn't jumped on this and started making them

I sent Mike the original design and plans when I first drew one up, and explained how to make one, basicly the same way I explained to MC, how to do it....I wish he could ..... but I think MC can make them for people, you will have to ask...

Yes until Mike decides to make them, I can make the CDs for the ERevo tranny.

Thanks Ray, really appreciate it. I sent you a PM looks like 4 now though two other mates want them + the 2 for myself- hope you're making something on these though considering the price and what they are I think its a bargain.
Still feeling guilty at getting you to do it, love to do it myself but lack the tools and time.

Mate the carbon bulkhead ties i got off you nearly 6 months ago are still going strong too.

If you saw the tools I used to build mine you would fall over laughing. 1970's era bench grinder and 1950's era drill press. The key thing is getting the right drill bits, carbide. I'd like to say the spot annealing helped, but I have no baseline to compare it to.

Wasn't someone playing around with using a Kyosho plastic spur instead of the hardened steel spurs? How did that turn out?

Simply have no dress press champ- i use a fold out bbq table for a wrokbench with a plastic chair atm lol.

lol I have a 60's era Craftsman drill press :mdr:

Well to keep this thread up and alive... I just bought the items needed from AMAIN and I will try my hand at making one of these.

With threads rolling through about everyone trying to make a maxx cd, I thought this route was better as I can retain the Slipper assembly. With Mikes Maxx CD mount that is supposedly coming soon I would need to spend extra on a slipperential and I am short on $$.
I am going to be installing this into a 3905 maxx; (same tranny an Erevo) I dont think this will work with a 3906.

Anyhow I will keep this updated for anyone... And thanks everyone for putting all this together...

well mine is still going strong!! thanks for showing us how mr crash :yipi:
really simple design.
but now i have this losi smart diff here in my room...but i'm currently happy with the XXL diff i have got in there...what do i do?
run the smartdiff anyway?

I'm just wondering which version of the CD you are going with......

It would be nice to know if it can be done with the smart diff innards. If you try it, keep us informed of how it works. From what I know (and I don't know much) the smart diff uses the same diff case with the metal inserts and the same ring gear. I just don't know if the extra parts that go inside the smart diff would catch on the two screw heads for the posts that secure the output gear. If done well, the screw heads are well below the inside surface of the ring gear but I just don't know if that's enough for the smart diff mechanism to not catch or rub on them.

it can, i converted mine as soon as i got it back from you

you have to use the losi heavy duty diff cup, it all drops right in

Interesting, I thought about doing this myself, but I figured if it wasn't broke don't fix it. Also, how does it perform in the erevo tranny?

So we have one confirmation that the Losi Smart diff can be used for a CD on the E-Revo. That's cool. Now we need an update on the performance like sjcrss said. Get to work Semi :whip: :mdr:

i agree, the price of doing it , kinda kept me from trying it, I wanted to, but the funds needed to be used elsewhere....if it works out great, I may just do one myself....keep us posted.

i love torsion diffs, i run them in everything :lol:


i would love to tell you all it rocks and you all can't live without it but i live in MN, there is afew feet of snow on the ground and it is below 0 outside even in the daytime (really its been nice this week, mid 20's) so i dont think i will have my revo out for afew months.

its been winter along time, i think i rember seeing the sun in june or was it july?

Ok so I received all my Parts to complete this diff.

I am going to use a Losi Heavy Duty Case, LST bevel Gears and an 8ight B-1.0 Spur I had laying around.

So my main question is when putting the holes in the Traxxas Output shafts Is the Correct measurement .190" from end of shaft to center of the hole being drilled?

Just a bit confused from Mistercrash saying .190" on an OFNA diff output. Yet I am using a LOSI diff. I want to be certain that this is correct for the LOSI diff as well.

THANK YOU GUYS!:smile:

It's funny because the first time I took that measurement, it was because someone was asking about it. The only concern I had making that hole was for it to be well centered in the shaft. For the rest, I just went by eye and tried to match the location of the hole in the Losi output cups :lol: 0.190'' is fine and don't worry too much about it, worry more on making your holes centered on the shaft so that once the pin is in the hole, the shaft slides in the gear without too much force.

After looking at the losi diffs, I noticed that if the post holes were countersunk deep enough, the smart diff parts would drop right in. I was planning to do it as soon as I got mine back, Crash, but after doing some reading on people using them in e-buggies and truggies, the fact that there is no clutch on e-motors means that the center might act a bit odd (it's meant to have a freewheeling drivetrain in the rest position) I'd be curious to hear how it goes though. I think I'm going to run a SD in the front of my revo but leave the center as a regular diff.

Semi, I'd definitely love to hear some results when you get a chance to test it. I know in nitro truggy, the SD center and front is all the rage, but the reviews become a bit more mixed e-truggies.

the diffs dont and can't freewheel, the spider grears are ALLWAYS makeing conection, allot of people talk about torsion diffs that dont know what they are doing because the have never used one or havent used them enuff.

the easy way to look at a torsion diffs is it's a diff that just act like a variable fluid weight diff from about 1k up to 30k or so when controling wheel spin

here is a link that may help you AMorgan
http://www.rc-monster.com/forum/showthread.php?t=25229

Torsens dont work that way, a torsen diff has the ability to bias the torque without any slipage. It can bias up to 3 times more torque to one axle than the other.

On acceleration it will send up to 3 times more torque to the rear. After that ammount the front will start to slip (or lift!) and If an axle is on the air it can transmit any torque and 0*3 = 0. In theory is impossible to pop a wheelie with a center torsen..

A viscous differential will send equal torque to both axles until one loses traction, at that point it will start to send power to the axle with more grip according to the viscosity of the fluid and the difference of speed... And it will do so on and off power, while torsen in off-power acts as an open diff, improving both on and off power turning...


If the available torsens can stand the torque of a MMM they will be ideal!!!