RB5 + Gear Diff?

[Mangan]

Hi,

Does anyone know if the gear diff from the Ultima SC can be fitted i the Ultima RB5?

//Mangan (Sick & Tired of the constant maintenece of the ball diff)

[fastinfastout]

I actually found the kyosho diffs to be one of the best.

they are very smooth, and do not require as much maintenance as say, AE and losi.

In the space of 9 months I had my car, running nearly everyday, you would not believe that I only overhauled it.......once!

[Gayo]

Good balls helps too
I use Acer ceramic ones on my FS and I see no need for a gear diff, unlike AE and TL ones.

[tsan]

I'd be interested in this too. As good as the RB diff is, I'd like to try out the gear diff if it fits.
Anyone have an SC manual? I can't seem to find one online.

EDIT: NM, found it. http://www.kyoshoamerica.com/manuals.php?category_id=1

[baw888]

Gear diffs have a different action under load. Gear diffs have a generally linear resistance to turning;
Ball diffs act like a proper limited slip diff should, light action when turning, then a heavier/stiffer under acceleration.

[njc11]

Originally Posted by Mangan

Hi,

Does anyone know if the gear diff from the Ultima SC can be fitted i the Ultima RB5?

//Mangan (Sick & Tired of the constant maintenece of the ball diff)

Yes they do fit... i have one built up to try.. so will post my findings as and when i try it!

The geared diff in the SC is spot on.. ive not had any hassles with it what so ever.. BUT ive never tried a ball diff int he SC!

[tsan]

The only thing I've noticed so far is the gear case has a slightly different number. The RB5's is UM508, while the SC is UM508B.
Here's what the SC's exploded gearbox looks like:
( clicky )

[Neil Skull]

The B number is irrelevant.
It means they have modified the tooling at some point. but its still the same part and will retro fit no problem.

[Rebelrc]

This gear diff...is it tunable ie oil filled?

[rcpower]

what was the outcome of your rb5 GEAR diff test?

[njc11]

I never tried it TBH..

I took the geared diff out of my sc and replaced with a ball diff... simply because the outdrives of the kit geared diff had ridges worn into them from the cvd's and there was now alot of slop..

But with running the ball diff in the SC for a good while now i dont think i will be going back to a geared one again... seems so much smoother to drive with the ball diff. So with these findings i wont be trying a geared in the lighter smaller RB5.

[RogerM]

I rebuild my RB5 diff about twice a year .... if they need them or not!

I use the Kyosho ceramic balls and pay attention to the finish on the diff plates, build with Nuclear greases and enjoy ... for months and months and months