Granite Spur Gear Stripped

[MRSRT8]

Good day gents,
I noticed my son's Granite Mega 550 making a grinding noise when I pulled the trigger.
I dismantled the power unit and sure enough, the plastic spur gear completely stripped. Thank God the pinion gear is okay. No modification just stock motor.
Would this be covered by warranty? I have email to Horizon Hobby to voice out my concern, waiting for their reply.

 

[jondilly1974]

It’s a $5 part. Why would you even think about wasting your time with a warranty claim?

 

[MRSRT8]

It’s a $5 part. Why would you even think about wasting your time with a warranty claim?

Lol, I just realized it! Whether they will replace it or not, I have ordered an upgrade to a metal slipper set.

 

[jondilly1974]

Lol, I just realized it! Whether they will replace it or not, I have ordered an upgrade to a metal slipper set.

You will also need a matching mod 0.8 pinion for the metal spur.

 

[MRSRT8]

You will also need a matching mod 0.8 pinion for the metal spur.

Will do, thanks!

 

[Jay R]

You should always look at WHY the gear stripped. Stone in the box happens and you can try to plug the holes better. Too lose mesh, perhaps you need to adjust the motor mount....

 

[MRSRT8]

You should always look at WHY the gear stripped. Stone in the box happens and you can try to plug the holes better. Too lose mesh, perhaps you need to adjust the motor mount....

Is only a month old! The pinion meshed properly. Remember, is a plastic spur gear. I don't see any hole where rocks can enter.
Well, I can tell you one thing...we bash the heck out of it!

 

[Jay R]

Yes, could just be heavy shock or just bad luck.

 

[ButchEastus]

Is only a month old! The pinion meshed properly. Remember, is a plastic spur gear. I don't see any hole where rocks can enter.
Well, I can tell you one thing...we bash the heck out of it!

what about the slipper clutch? Do you run on concrete and if so how tight do you have it set? Mine was set too tight from the factory and I had to loosen it.

 

[MRSRT8]

what about the slipper clutch? Do you run on concrete and if so how tight do you have it set? Mine was set too tight from the factory and I had to loosen it.

We normally bash on the parking lot. The slipper clutch Is factory setting. I've already ordered a replacement HD spur gear, hopefully, it will solve this issue.

 

[ButchEastus]

I would adjust that slipper clutch if you only run on concrete. The slipper clutch helps take stress off other components especially on high grip surfaces. Cheaper to replace a slipper pad then internal components. Just my 2 cents.

 

[MRSRT8]

I would adjust that slipper clutch if you only run on concrete. The slipper clutch helps take stress off other components especially on high grip surfaces. Cheaper to replace a slipper pad then internal components. Just my 2 cents.

Thank you for your advice! ?

 

[NoMoreArrma]

Might be a $5 part... but it's crap that it happens so soon. 3rd time my son took out his granite, stripped. Replaced it, got 5 more runs out of it, stripped. Never even bashed it around. Just ran on gravel and road. First and last arrma product I'm buying lol

 

[Kla912000]

Is only a month old! The pinion meshed properly. Remember, is a plastic spur gear. I don't see any hole where rocks can enter.
Well, I can tell you one thing...we bash the heck out of it!

Might be a $5 part... but it's crap that it happens so soon. 3rd time my son took out his granite, stripped. Replaced it, got 5 more runs out of it, stripped. Never even bashed it around. Just ran on gravel and road. First and last arrma product I'm buying lol

You guys have to make sure the slipper is set correctly, that the gear mesh is right and that the motor mount isn't bent which will eat up spur gears real fast. Plastic or not the stock spur is plenty strong to handle the stock motors if everything is set properly, especially on the mega 550 with the weak brushed motor. I run my Big Rock on 4s brushless power and am still using the stock plastic spur gear that the truck came with when I got it over 6 months ago. It is not a fault of Arrma if you don't have your rig set up properly and are stripping spur gears.

 

[NoMoreArrma]

But on the 3rd run from the time of delivery with everything stock...
I appreciate the info though. That shouldn't need to be done on a brand new rtr.
It's all apart (again) now, so I'll double check the rest. But still. Shoddy.

 

[flipsim59]

Might be a $5 part... but it's crap that it happens so soon. 3rd time my son took out his granite, stripped. Replaced it, got 5 more runs out of it, stripped. Never even bashed it around. Just ran on gravel and road. First and last arrma product I'm buying lol

There's a reason for everything. If the same part keeps failing, investigate why it's failing. As for the spur gear being chewed up, the most common problem is a bent motor plate aside from improper gear mesh. You also have to check the pinion gear for wear. If the gears are sharp at the tip, replace it. I own a Senton and have gone through the same thing, so I went all metal spur (4 clutch plates), input gears, diff gears. Adjust the slipper clutch accordingly and just bash.

 

[Kla912000]

But on the 3rd run from the time of delivery with everything stock...
I appreciate the info though. That shouldn't need to be done on a brand new rtr.
It's all apart (again) now, so I'll double check the rest. But still. Shoddy.

I don't exactly believe that. There's gotta be more to it. I have 2 other Arrmas in addition to the 4s Big Rock and before I ever ran them I did my due diligence and went over the vehicles to make sure everything was set up correctly and all three trucks are still running the original stock spur gears from the factory.

 

[m.mahdi_sh]

stripping in mega is definitely a problem! it's definitely one of the three mentioned above, bent motor plate(which from what u said about bashing in the parking lot i don't think that's the case), dirt in the power module or under it(which again not happening that much in the parking lot!), gear mesh which is probably the problem. anyway check all of them. if u don't settle the problem it'll happen again. also check for movement of the motor(maybe a loose screw that let the motor move a lil bit) and probably use of a washer+blue locktite will do

 

[MRSRT8]

You guys have to make sure the slipper is set correctly, that the gear mesh is right and that the motor mount isn't bent which will eat up spur gears real fast. Plastic or not the stock spur is plenty strong to handle the stock motors if everything is set properly, especially on the mega 550 with the weak brushed motor. I run my Big Rock on 4s brushless power and am still using the stock plastic spur gear that the truck came with when I got it over 6 months ago. It is not a fault of Arrma if you don't have your rig set up properly and are stripping spur gears.

In my case isn't the adjustment (I had it adjusted according to specification). Actually, the slipper shaft was warped. I've replaced it, seems to be fine afterward. Guys, check the slipper shaft.

 

[Kla912000]

In my case isn't the adjustment (I had it adjusted according to specification). Actually, the slipper shaft was warped. I've replaced it, seems to be fine afterward. Guys, check the slipper shaft.
View attachment 150846

Good deal! There is always a reason for the spur stripping out. Doesn't just happen cause it's plastic. Glad you got it figured out.