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Hello, I took a look at my turbo optima pinion surprised to find it was a pitch 32 pinion. Is this correct does turbo optima use pitch 32? I was always under the impression it used 48p?

Techincally it's metric 0.8 module, but that's VERY close to 32 pitch and essentially the two are interchangeable.

Several 48 pitch conversions were available for the Optima line, so perhaps that's what you're thinking of.

Yes it must be, but was that part of the option house parts?

Robinson Racing made a vast line of 48p cluster gears for the car. Kyosho later released a smaller module pitch gear for the Ultima series of cars that that could be used on the Optimas as well. Thorp also made aftermarket gears, but I don't remember anything other than 32p.-Jeff

Jay Dub wrote:Robinson Racing made a vast line of 48p cluster gears for the car. Kyosho later released a smaller module pitch gear for the Ultima series of cars that that could be used on the Optimas as well. Thorp also made aftermarket gears, but I don't remember anything other than 32p.-Jeff

Were any of those aftermarket gear sets worth having? Other than giving you the ability to use modern pinion gears, what were the benefits besides overdriving/underdriving the drivetrain?

Mainly being able to run lower gear ratios for the brushed modified motors. Unfortunatelly, Robinson has always had quality issues, and many time the gears were so out of round that the smaller pitches would strip (because the kyosho cluster gear was so small). Also, with the 48p gears, one could get a more accurite ratio, or make finer adjustments. -Jeff

I wouldn't mix metric with DP... yes it "works" but the mesh is still not 100% right and the wear is much, much faster...

Paul

Lonestar wrote:I wouldn't mix metric with DP... yes it "works" but the mesh is still not 100% right and the wear is much, much faster...

Paul

X2

0.8 module is 31.75 p. I've found they work just fine together if you set the mesh correctly.

Allow me to insist

Lonestar wrote: yes it "works" but the mesh is still not 100% right and the wear is much, much faster...

Thorp did release the 48 pitch conversion...and offered an over drive kit and an under drive kit. Similar parts were also released under the trinity name.

The under drive kit allowed a better range of gearing when running a mod motor.

This topic brings up a question: How do you guys properly set your pinion gear mesh? If I remember correctly, either the Optima kit or some other kit I built came with a little strip of plastic that you'd mash between the 2 gears to properly adjust the mesh. That strip of plastic is now long gone, but I've used the corner of a plastic Ziplock bag to do this. What do you guys do?

Lonestar wrote:Allow me to insist

You're allowed, but I'm also allowed to disagree.

Coelacanth wrote:This topic brings up a question: How do you guys properly set your pinion gear mesh?

My method is to allow for just a small amount of "rocking" movement between the pinion and spur teeth, checking it at several places along the rotation, as molded spur gears are rarely perfectly round. Some people use a strip of paper between the teeth, which would give about 0.1 mm clearance.

Coelacanth wrote:This topic brings up a question: How do you guys properly set your pinion gear mesh? If I remember correctly, either the Optima kit or some other kit I built came with a little strip of plastic that you'd mash between the 2 gears to properly adjust the mesh. That strip of plastic is now long gone, but I've used the corner of a plastic Ziplock bag to do this. What do you guys do?

For Kyosho rb5 which is pitch 48. manual says use piece of paper between pinion and spur gear while tightening/