Direct Drive to Diff E Revo Build

Originally Posted by sikeston34m

8S1P A123 is 1lb 6 ounces. What ESC will you be going HV with?

Thanks, I seem to like the jazz controllers the 55-32-10 or something like that. I have not decided yet though... Also, those tires look great!

Off topic question, would a 63v 3300uf 85c cap be ok on my quark 125? I know its not low esr, but since its so big, would it work? I have 2 of them....(from an older bass amp)

Bye

[squeeforever]

I LOVE the Phaltlines!

[zeropointbug]

Sike, this is coming together really nicely man. It's looks fine with the 10Ah lipo's on there... that would make for some nice runtime at that, 40 mins at least at 40 mph.

[JERRY2KONE]

Hey Sikes thanks for sharing this project info with all of us. This thread has been a pretty educational venture. We are learning at your expense and that will help a lot of us decide how to proceed on some of our own builds. The trucks setup looks really good, and the direct drive is a unique concept for that truck. With those street wheels and tires you should be able to get some pretty fast runs. keep up the good work. We are having fun just reading through your experience.

[johnrobholmes]

done yet? Got an hour of test time too? :D

[BL_RV0]

hurry your ASS up! j/k, take your time and do a good job.

[DrKnow65]

Any thoughts on a centrifical clutch setup for a direct drive brushless? It would have to stay engaged (spelling?)under braking and work at a low rpm. Wouldn't this fix all cogging issues?

I'm picturing a clutch (old old school) that had two weights on levers that would spin out with rpm, pushing (leverage) on a clutch disc. I remember seeing them on elevators for speed brakes and at a power pland to control a turbine flow valve. Hope you know what I'm jabbering about :)

I also saw a modernized version for harley davidsons that used sliding weights that spun between two concave washers to apply force to the clutch. I'll see if I can find a photo to help you all understand.

[DrKnow65]

Here's a link to the harley autoclutch, but I couldn't find any photo's of the internals.
http://www.efmautoclutch.com/

Basically there are two plates with tapered grooves (channels) from the center out (large groove at the center, getting smaller twards the outside). There are balls (weights) that are in the groves, when the rpm's increase the balls are pulled outward by centrifical force, this wedges the balls farther into the grooves and pushes the two plates apart, applying force to the clutch pack.

[sikeston34m]

Originally Posted by DrKnow65

Here's a link to the harley autoclutch, but I couldn't find any photo's of the internals.
http://www.efmautoclutch.com/

Basically there are two plates with tapered grooves (channels) from the center out (large groove at the center, getting smaller twards the outside). There are balls (weights) that are in the groves, when the rpm's increase the balls are pulled outward by centrifical force, this wedges the balls farther into the grooves and pushes the two plates apart, applying force to the clutch pack.

That's a pretty interesting design. I think there is much improvement to be seen in the "clutch" area of RC. I wish someone would design a clutch for RC that works like that.

Most "slipper" clutches that are used today are designed to "protect" the drive train, but they also hinder acceleration. It's really the fact that it never truly locks up that does this.

I'm almost 100% positive that I have the answer to the cogging. These diffs will change how everything acts. With the Phaltline tires and the 4.3:1 diffs, Rollout is exactly the same as the E maxx outrunner setup in 2nd gear. This is gonna be awesome because this is SOOOOOOO much tougher.

I got the Diffs assembled. They look great inside and out. I also figured out the CVD arrangement. Now I have to split the bulks to install them.

For all you guys taking notes here, the RD Logics CVD's work with the Hotbodies diff cup. The THS Racing cvd's do NOT work with the HB cup.

[Matthew_Armeni]

Maybe I'm wrong, but doesn't a Centax clutch work like that? Or is it the balls themselves that apply the direct force on the clutch? I know that it uses balls set in a concave hole so when the flywheel spins the balls are forced outward but the shape of the hole they sit in forces them forward as well. What I don't know is if they touch the bell or touch something else that in turn touches the bell. Any thoughts?

[sikeston34m]

Well I got the front end tore apart and the Bulks split. This is my first time tearing down a Revo. I'm impressed with the design. It's a tad more complex than the E maxx.

I took out the front stock diff. There's something wrong with it. It's leaking grease everywhere. When I spin the pinion, it feels like the ring gear inside is warped or something. It spins freely for about 1/3 of turn, then I feel the gear mesh and there's ALOT of drag. Hmmmmmm.........Aaah well, I'm not gonna trouble shoot it right now.

This does point toward the fact that this diff was dragging the setup down though.

The RCM diffs feel sooooooooooo smooth and spin VERY freely.

@Drknow:

Let me get this perfected. I'll show you the EXACT setup to go with and some video's.

[lincpimp]

Originally Posted by sikeston34m

Well I got the front end tore apart and the Bulks split. This is my first time tearing down a Revo. I'm impressed with the design. It's a tad more complex than the E maxx.

I took out the front stock diff. There's something wrong with it. It's leaking grease everywhere. When I spin the pinion, it feels like the ring gear inside is warped or something. It spins freely for about 1/3 of turn, then I feel the gear mesh and there's ALOT of drag. Hmmmmmm.........Aaah well, I'm not gonna trouble shoot it right now.

This does point toward the fact that this diff was dragging the setup down though.

The RCM diffs feel sooooooooooo smooth and spin VERY freely.


@Drknow:

Let me get this perfected. I'll show you the EXACT setup to go with and some video's.

Sounds like the inside bearing on the pinion let go and the ball bearings are floating around inside the diff. I had the same problem with my tekno revo rear diff. It only had 3 different nitro motors and 1 hour of hard brushless running! Maybe some better bearings, boca avid etc, would be the ticket. They may be expensive, but would sure roll nicely.

[DrKnow65]

Keep good notes of this buildup for me OK Sike? I won't be able to do it too soon, but imitation is the most sincere form of flattery :) I think I'll be converting my hyper7 befor I can do the DDR (direct drive revo) but I'd like to do direct in both of them. Eventually....

[its me]

I am also digging this build and dieng to see the end results :)

[MetalMan]

This truck has caused me to stop procrastinating on turning my MT2 into a direct-drive outrunner-powered truck. Now I have everything I need, except for the custom shaft that still needs to be made.

Thanks a lot