Destroyed Pinion/Spur Gears

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Arrma RC's
  1. Fazon

I'm new to the RC world since two of my kids decided to buy some Rustlers. I had some money to burn so I opted to pick up a Fazon. I've only run it a hand full of times with SMC 7200's. It went down today, and I discovered the pinion gear and spur gear were completely sheered with few teeth left. Do these cars require adjustments to the gears before driving? Any info would be greatly appreciated. Thanks in advance.


Arrmas pinions are kinda weak,if the gap between the gears is to large more energy is transfered thru the tip instead of at the base of the gear leading to breakage.Robinson Racing makes hardened pinions,for the spur you need the stock gear(spur doesn't usually fail).
I'm thinking they got a bad batch of gears sometime in the last couple months. We hardly heard of chewed pinions and now a lot of folks are reporting them on the first couple runs. Seems to me that they might have gotten the mixture wrong in the alloy or messed up the heat treatment on a batch and this is the result.
It's also possible the gear mesh was a bit off out of the box. Do some research on gear mesh and watch some how to vids, or take it to your LHS and have them verify the gear mesh is good. Luckily the parts are not that expensive. Use this as an opportunity to learn your Fazon and do some wrenching.
I have only had one spur gear go on the one time I didn't check the mesh from the factory. I just ran the Nero straight out of the box. I did a few runs before it broke.
Yeah the spur gear was chewed up and teeth were sheered off. I don't have a picture since I haven't broken it down yet. I went with the Robinson Racing pinion gear that was suggested and the optional "machined steel" spur gear from Arrma. Hopefully that'll solve the issue when adjusted properly. Thanks for the help.
Has anybody tried to get them replaced under warranty or has everybody just upgraded and picked up the hardened gears?
I just now chewed through a pinion and spur gear. Ran the Nero through 16+ sets of batteries, had all the diff servos fry and replaced, not an issue. Run a fresh set of packs in open diff, just fine. Run it in all climb mode, all diff lock, fine. Set to wheelie mode, fry the pinion and spur. I set my gears already to minimal play, just enough to not bind. Now this. Is there a sweet spot to the gear mesh or is it just the common opinion that there was a bad batch of gears made and we need to buy the Robinson Racing gears?
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