Granite Need help on choosing spur/pinion gearing

Jackhammer

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I'm completely ignorant about gearing at the moment. I have a stock Granite 4x4 Mega. I want to swap over to a Max10 SCT-A combo, run on 2s lipos. It's a 3660 motor at 3200kv.

Here's what I want out of my gearing. I want to keep the motor cool as possible, I want more torque than top end, but if at all possible, still be able to break like 40mph if I put it through the floor. Though that last one is the least important.

I blew my stock spur tonight. LHS didn't have correct pinion gear, so the one they gave me made the mesh too tight. I hollowed out a couple holes in my motor mount to allow me some adjustment, and I'm guessing I was too timid in tightening the motor screws (really afraid of stripping the motor screws holes). So during my first run with the new lipos, the motor moved out a tad, and rounded off all my teeth. I have to purchase a new spur no matter what. I'm guessing the blx spur will be the big suggestion? Also, the Max10 comes with a 21 tooth 48 pitch pinion. What should I be looking at for my gearing both before and after the upgrade? Until I get the new electronics, should I just replace the stock gear?

Any and all help is appreciated. Trying to learn a lot as fast as possible, but there's a ton of info to sift through.
 

Bryank930

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Get an adjustable mesh motor mount. That, with the BLX spur/slipper assembly and a 20T pinion will put you around the 40mph mark on 2S. Things might get warm though. I'd stick with the BLX slipper setup with a 17T pinion. That'll give you high 30's top speed and plenty of torque. Or even drop down to a 15T pinion to play it safe.

If you really want speed, just get a 3S battery and even with the 15/57 pinion/spur, you're looking at around 50mph top speed.
 

chazekxt46

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I ran the hr steel spur with a 17t pinon worked fine.
 

suchtragedy

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The 21T/48P isn't going to be a good fit for your granite, the tooth count is too high and 48p gearing is going to be very weak to hold up to brushless. If you need to get a spur anyways get the 32p blx spur or entire blx slipper assembly.

If using the 3s blx spur/slipper with the blx non-adjustable mount then stick with 15T or 13T pinions and it should run decent, 20T is too big for 2.8 MT tires and the motor will run quite hot and it will cog on 2s in grass/rough terrain, at least this was my experience when running 2s with 20T on a granite.

If you get the adjustable motor mount you need to be sure to set your mesh right and make sure your screws are tightened properly with locktite so they don't back out this time.
 
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