RayJrr

I have an Axial Yeti and I replaced the plastic spur with a metal one from gpm racing. It was noisy so I adjusted thr motor position a few times trying to make it less noisy.

After about an hour the spur had worn the pinion gear down to a nub.

Is there something I can do to prevent this from happening again? Or do I need to switch back to a plastic spur ?

RustyUs

Sometimes a manufacturer will "goof" on the composite for certain parts, and have a so called "bad batch". Sometimes a manufacturer won't care and only intends for their product to handle lite duty, and then you have to hope for aftermarket parts to show up and fill the void. That being said, I found nothing wrong with the stock Axial Yeti spur gear. I was running a 1/8 scale motor, and 3S LiPo setup...spur gear was handling it just fine. Me personally, I would run a plastic spur gear whenever I can. Now the rear axle's output bearing is another story .

What brand of pinion gear were you using?

seedygreenute

The softer metal will usually be the one to get eaten up . In your case , the pinion gear .

flyinwalenda

My Feedback: (5)

Are you sure you had the correct pitch on both gears? If say one was 1mod and the other 32p, one is going to "wear" into the other .
Proper gear mesh is very important.
As mentioned you need to have a hardened steel pinion.

RayJrr

The spur I have on there is this one:
https://www.gpmracing-parts.com/axia...-90068813.html

I just ordered this pinion gear:
https://www.amazon.ca/dp/B001SEVSN0/..._nbzJzbMYZ8V1M

Both look like 32p and hardened steel. I should be in good shape now. Thanks for thr help.

flyinwalenda

My Feedback: (5)

If the Traxxas one doesn't hold up try these:

Robinson Racing Products - Products and Pricing 5MM BORE MOTOR PINIONS

https://www.horizonhobby.com/extra-h...-5mm-p-rrp8614

The Saylors

i have heard pretty bad things about the metal spur gears. You are better off doing plastic and just keeping a couple on hand in your tool box.

RayJrr

Hi, What sort of bad things ?

flyinwalenda

My Feedback: (5)

The plastic spur gears are supposed to be a sacrificial part. When something goes wrong in the drive line, etc...the plastic spur will let go before anything else gets damaged and for a few dollars it's easily replaceable.
A metal spur will not break but rather allow the next weakest link to break.....usually something in the transmission.
High amperage, high speed/torque modified vehicles do better with a metal spur...as long as the rest of the drive line is beefed-up as well.

RayJrr

Ah ha, That's a good point. Thanks