How to pick Pinion and Spur Gears

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quad_rocket

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Are there any standards on the motor shaft diameter? How do I know which pinion gears will fit on a motor?

I do understand mod and tooth count, just not sure how I go about getting or creating a kit of different size pinions (and spur gears) that will fit my 1/18 and 1/10 scale motors.

I also understand that the wrong gear combination can lead to mayhem, but it's a hobby and I want to push the boundaries.

Thanks!
 
Most motors are either 1/8" (3.2mm) or 5mm. Most 540 / 3650 and smaller motors are 1/8" shaft, most bigger motors are 5mm, and some of the 1/5 scale motors are 8mm I believe the Mega brushed motors are 1/8" shaft, but the current gen BLX motors are 5mm (not sure of the 8s Firma motors).

Also important is the gear tooth size. The Mega use a 48p tooth, and BLX3/4 use 32p / Mod.8, and the 6s cars use Mod1.

So if you have a BLX3s Granite, you need a 5mm bore, 32p(M0.8) pinion.
If you have a Mega, you need a 1/8" (M0.8) bore 48p pinion.

Make Sense?
 
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Most motors are either 1/8" (3.2mm) or 5mm. Most 540 / 3650 and smaller motors are 1/8" shaft, most bigger motors are 5mm, and some of the 1/5 scale motors are 8mm I believe the Mega brushed motors are 1/8" shaft, but the current gen BLX motors are 5mm (not sure of the 8s Firma motors).

Also important is the gear tooth size. The older Mega use a 48p tooth, the newer mega and BLX3/4 use 32p / Mod.8, and the 6s cars use Mod1.

So if you have a BLX3s Granite, you need a 5mm bore, 32p(M0.8) pinion.
If you have a V3 mega, you need a 1/8"(3.2mm) bore 32p(M0.8) pinion.
If you have a V1/2 Mega, you need a 1/8" (M0.8) bore 48p pinion.

Make Sense?
Arrma 8S motors are still 5mm. ?
 
My v3 mega senton had 48p when I bought it not 32 althought I did change to the whole .8 mod slipper assembly

Thanks, I fixed that. I thought for sure I had read the V3 Megas came with the same slipper and spur as the BLX trucks. But, I checked the exploded diagrams, and dang, it still has the same slipper - just updated with the castellated pads.
 
Yeah it makes sense.

I got an aftermarket Hobbywing 7200kv brushless for my MiniT2.0 and after digging online I found the diameter for that motor shaft was 2mm. It is not on the outside of the sealed box.. And it appears the stock MiniT2.0 motor shaft is 2mm too.

As for my Granite BLX, I had heard from this forum that the original gear mesh was way too tight. So one of the 1st things I installed was the adjustable motor mount. So now I know the shaft diameter, I am set now!

Thanks!!
 
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