RC10Talk - The Net's Largest Vintage R/C Community

I'm sure this has been answered a dozen times, but I can't seem to find it.

I'm planning to rebuild and experiment with some modifications on one of my 6-gear transmissions. Is there a better spur/slip assembly currently (and readily) available for these? Would it require a different currently (and readily) available differential shaft? If so, can someone point me in the right direction?

Thank you in advance!

It's actually the diff, not a slipper. There's really nothing that can be done with it.

+1,

If you are building a runner convert it to a stealth trans, much better!

I clearly have little knowledge about rc cars at the moment. The part where the spur gear is essentially "clamped" between two washers is not called a slip assembly? What is that assembly called?

That part kicked my butt about 20 years ago. No matter what I did, the gear would just spin, and the wheels wouldn't spin when I squeezed the throttle. Living out in bfe away from any form of modern civilization or even internet, I didn't have anyone or anything to help me figure out what I was doing wrong. For all I know, I could have rebuilt the transmission incorrectly.

With help from this site (and finally having an instruction manual), I'm confident it won't outsmart me this time. haha

Hi,

It is a ball differential.

Make sure you use the correct Associated lube on the balls.

In the 6 Gear transmission, the ball differential is external and adjustable by the nut on the topshaft. Newer transmissions, like the Stealth, have the ball differential (or gear differential) internally to the transmission case where you set it and forget it (for the most part). They then have a slipper clutch on the top shaft that is external and becomes your primary adjustment.

And to add a little confusion on newer cars, sometimes people eliminate the slipper entirely.

As some have said, the only upgrade is to go to a stealth transmission. If you're actually running the car, it's the way to go regardless. I'm also one of those people who eliminates the slipper if possible.

Thank you for the information and advice guys!

I disassembled the tranny last night and discovered that I definitely did NOT know what I was doing 20 years ago. Missing bushings, gears not all the way in place, etc...

It'd be nice to upgrade to the stealth tranny, but I'd rather not drill the necessary holes in my chassis....plus my engineer brain wants to experiment with various modifications to a few re-release 6-gear transmissions and see what happens (R&D has always been my favorite part of engineering). If none of my ideas work (which they probably won't, but I can't help wanting to try), I'll buy a different chassis and upgrade to the stealth tranny.

you can build them pretty bulletproof if you take special attention to building the diff, running it tight, and then, replace the idlers with outdrive gears with the outdrives cut off. this would make the trans all metal, so you would need some smidge of lubrication on the gears. but this would be bulletproof to the point that any damage that would occur would be from slipping the diff enough to melt the spur gear.

Unless you have a rare unmolested car that you don't plan on ever actually using, drilling the holes for a stealth tranny isn't really a detriment if done right. Or pick up a spare chassis, they are relatively cheap even new.

I've not tried this on a 6 Gear but Kyosho Option House used to offer a pinion gear with an integrated torque limiting slipper. It adds rotating mass, but is a cool option.

- Limestang

.

I've had good results with the 6 gear diff by sanding the diff rings and using a Kimbrough spur gear. These gears have holes for extra balls which increase the friction to reduce slipping.

Hi Harvey,

This will be going in my RC10 book, I use the Kimbrough spur gears with the extra balls,

but never thought of it as a hot up, I will try sanding the diff rings as well.

Thank you,

It is also a good idea to pin the diff rings to the carriers, most racers in the UK would super glue or araldite(epoxy) them. I always used loctite 270 the green stuff on both diff rings and on thrust washers.
I also used to change the gold 5-40 nyloc nut from time to time.

One thing I have noticed is that the diff shaft is shorter on older cars not allowing correct thread protrusion on the gold
nyloc nut.
Can anyone confirm this ?