RB5 Gear Diff Mod
 

Hello fellow RB5 drivers,

Have anyone of you encountered someone who have done a geardiff mod on the RB5? Please share if you have any know hows.

Thanks

Regards
Calvin

I run an Ultima SC gear diff on my RB5-based MCS. I had to dremel slightly the diff screws and the gearbox in order to avoid any friction, but I think it is a drop-on fit on the roomier RB5 gearbox.

I had to buy the parts separately as Kyosho doesnt sell it as a unit.
-KYOUM605 (gear set)
-KYOUM610 (bevel gear set)
-KYOUM613 ((bevel shaft set)
-KYOUM612 (outdrives)
-KYOUM611 (gasket) (not sure if needed, read below)

I filled it with 3000wt Kyosho oil but it quickly made a mess on my gearbox, oil everywhere and none into the diff :cry: So I filled it once again, but I used silicone bathroom sealant instead of the paper gasket and under the diff screws.
So far so good, after 2 trainings on our outdoor carpet club track (roughly 2 hours of track time) the diff is fine, smooth, with all the oil still inside ;)
Don't forget to set your slipper properly as there is no give on a gear diff.

I see on Red RC that Kyosho is about to sell steel diff gear : http://www.redrc.net/2012/04/kyosho-...Car+News+DF%29

indeed a perfect fit in the normal RB5 gearbox,parts:
um605
um610
um611
um612
um613
ORG045S, must use them for no leakage, used 1000 cps for a smooth balldiff feeling :thumbsup:

Oops, I forgot the ORG045S o-ring.

Yes, 1000cps must be good. My 3000cps diff feels a little too stiff, awesome for traction but a little glued on hairpins.

Thanks for the respond guys. Got any pics to show?

Regards
calvin

nothing special, here is a gear- and balldiff. I've used it for a few day's on an indoorcarpet track. Have yet to try it outdoors on a dusty loose track ;-)

Yeah, i purchased the parts already and have already assemble the gear diff, so far no leakage. But i got one question, when i tighten the diff case screws the diff action becomes very tight is that normal? or i should not tighten the screws so hard?

Thanks

Regards
Calvin

The diff needs a little run-in to feel free, but don't torque the screws, finger tight is enough.

has anyone tried this in a vega gear box?

Thanks man :)

Thanks for the handy pics :)

Just a quick question .... why would you want to replace the silky smooth and long lasting Kyosho ball diffs anyway? What are you trying to achieve I mean?
Just curious.

nothing wrong with the lovely ball diff,but i for one would like to try a gear diff,nothing wrong with the RB5 but that didnt stop me making it into a Vega:thumbsup: