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Guys I cant remember the part number for the 'HARDENED' final pinion gear for the Optima. I'm currently looking for one and need to know the number.

Thanks in advance, Jason.

OT-76

Thank you.

Good luck in your search...those things are damn hard to find! I bought an Optima parts lot from a forum member several months ago, a box filled with random bits & pieces, nuts & bolts, and a lot of crap...but there was a hard final pinion gear in that lot, like finding a gold nugget in a pan full of gravel!

bormac i have a few along with some ot74 slipper gears, let me know if u still looking and i can find one tonight, have a bunch new and used i believe, the used ones were in perfect shape i believe too.

Is that he same as the Ultima's?

Diggley wrote:Is that he same as the Ultima's?

Perhaps the original Ultima, yes...but the Optima Mid and later ones had a plastic final pinion gear.

Diggley wrote:Is that he same as the Ultima's?

I used one from an Ultima Pro gearbox when I put my Optima together.

I think you could just use a 19 tooth, 32 pitch pinion to suit a 5mm shaft. Like this

dangermouse wrote:

Diggley wrote:Is that he same as the Ultima's?

I used one from an Ultima Pro gearbox when I put my Optima together.

I think you could just use a 19 tooth, 32 pitch pinion to suit a 5mm shaft. Like this

Anyone want to take a chance on a gear like that? It's occurred to me a time or two already, but there's a number of little details that make the hard final pinion gear different from a motor pinion. For starters, the teeth and overall height of the Kyosho gear are much longer than typical motor pinions.

It wouldn't surprise me if you could make it work.

When I had a quick look before, I ran a 32 pitch pinion around an optima diff gear and the mesh is fine. Actually I just went and compared a new 19T 32P tamiya pinion against my old optima final drive pinion. Both have the same diameter.

Obviously you would need to look into the width of the gear, and possibly make adjustments via trimming or shimming to suit the gearbox housing.

I may be wrong, but those 32p pinions with 5mm bores are what is used on the big 8th ebuggies. I would think they'd be tough enough for some Optima use, if they handle that kind of power and abuse.

they arent 32pitch, they are like the metric pitch i believe, whatever that is called

32 pitch in metric is 0.8 module. They're very, very similar...close enough to interchange in most cases. 48 pitch vs 0.6 module and 64 pitch vs. 0.4 module are far enough off to create mesh problems.

Diggley wrote:Is that he same as the Ultima's?

Optima, Salute, Javelin, Ultima, Turbo Ultima, Ultima Pro, Ultima Pro XL and Sideways can use this gear (OT-76)!

.8 module is roughly 31.8 pitch. Close enough to 32 pitch to use.