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

Just picked up a 2nd Turbo Mid and in tearing it down I found it has the Option House Ball Diffs in it. Does anyone have an instruction sheet for these diffs? At the very least, anyone know what size diff balls they used?

Will this help?

That definitely helps! Can't see clearly enough though if there are any sizes on there for the diff and thrust balls. Can anyone make it out?
Thanks for the help!!!!

3mm diff ball you need. 3mm diff ball is also used for Ultima and Lazer (From ZX to ZX-S).

Kyosho's early ball diff system exists 2 kinds for Optima mid and Ultima series, one is no separated diff ring and the other is WBD-3 diff ring is inserted into it.

cpebach wrote:3mm diff ball you need. 3mm diff ball is also used for Ultima and Lazer (From ZX to ZX-S).

Kyosho's early ball diff system exists 2 kinds for Optima mid and Ultima series, one is no separated diff ring and the other is WBD-3 diff ring is inserted into it.

Thanks a ton!!!! Now I just need a rear ball diff gear and I'll be golden

the diff ring part no. is WBD4 not WBD 3. Sorry~

WBD3 is ball diff pully(Optima mid) and diff gear(Ultima) set

Ceramic diff ball would be ultimate choice.
I also restored Turbo optima mid special and Turbo optima mid SE with ball diff parts.

Hi everyone, I'd like to necro this thread for help. I have an Optima Mid that I'm restoring as a runner. I believe it has the early model rear ball diff that has the diff halves but no diff washers. There are light grooves worn into the halves. Will it run ok, if I just put new diff balls in?

Or is there any trick to maybe modifying the dif so I can use the dif washers?

Any other solutions?

I'd like to get this cleaned up to run at my local track for fun.

Thanks.

Woulves Baine wrote:Hi everyone, I'd like to necro this thread for help. I have an Optima Mid that I'm restoring as a runner. I believe it has the early model rear ball diff that has the diff halves but no diff washers. There are light grooves worn into the halves. Will it run ok, if I just put new diff balls in?

That depends on how worn it is.

Or is there any trick to maybe modifying the dif so I can use the dif washers?

Unfortunately not, besides replacing the outdrives with the ones from the later diffs.

Any other solutions?

I'd like to get this cleaned up to run at my local track for fun.

Thanks.

Pick up ball diffs with rings.