Big Rock So how long do you think this new set of RPM arms will last?

Hector_Fisher

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The stock ones suck. The RPM ones break for no reason (my 5 year old son has been driving this RC). Is there anything that is worth getting instead?
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QLynxer

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Lol man I don’t think anything is 5yo proof.

RPM is supposedly the strongest, the metal ones are tempting but don’t be fooled.

They’re more likely to break then plastic ones.

Did you boil the RPM before installing? I’ve read that if you boil them for a bit, it will increase flexibility even more.
I’ve also heard that in colder temperatures, the plastic becomes more brittle and perhaps that’s why yours snapped.
 

Tex Koder

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The stock ones suck. The RPM ones break for no reason (my 5 year old son has been driving this RC). Is there anything that is worth getting instead?
View attachment 261563 View attachment 261564

You may want to look into upgrading to the new 4S v2 arms.
Which would involve not just the arms, but also the CVD driveshafts, steering block ,C-Hub and Rear Hub block.
Something to consider..
 

slick2500

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The stock ones suck. The RPM ones break for no reason (my 5 year old son has been driving this RC). Is there anything that is worth getting instead?
View attachment 261563 View attachment 261564
1 run.

The a arms almost always break in the same spot, it is a design flaw for sure. https://www.arrmaforum.com/threads/...-4s-models-lets-see-your-broken-a-arms.23481/

-edit- I completely forgot you already knew about that thread. I know people are breaking these arms but the fact that no one posts them in that thread kind of annoys me as Rpm will say it isn't a problem with so few people having posted in that thread.
 

Hector_Fisher

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1 run.

The a arms almost always break in the same spot, it is a design flaw for sure. https://www.arrmaforum.com/threads/...-4s-models-lets-see-your-broken-a-arms.23481/

-edit- I completely forgot you already knew about that thread.
Thought about posting in it again. But I couldn't find it and was lazy so I started a new one.

Either way, the 4s arm mod may be my best bet. It seems to be super random. I've thought about taking up RPM on their warranty about the arms but I've heard they are difficult to work with.

I wonder if RPM even knows their 3s arms sucks.
You may want to look into upgrading to the new 4S v2 arms.
Which would involve not just the arms, but also the CVD driveshafts, steering block ,C-Hub and Rear Hub block.
Something to consider..
That's a hefty upgrade.
 

slick2500

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Thought about posting in it again. But I couldn't find it and was lazy so I started a new one.

Either way, the 4s arm mod may be my best bet. It seems to be super random. I've thought about taking up RPM on their warranty about the arms but I've heard they are difficult to work with.

I wonder if RPM even knows their 3s arms sucks.

That's a hefty upgrade.
I've pretty much given up on my 3s Arrmas, I got sick and tired of having to rebuild the motor and slipper every 3-4 runs. The motor out of my Typhon has been in my Rustler since August and after dozens of runs I haven't even though about checking the motor bearings because I know they aren't packed with dirt. And the Senton is just a big ol pile of crap every time my nephew drives it he breaks something on it. It runs on 2s only with a 15t pinon, he isn't allowed to jump it and you can't run into stuff in a wide open area. The 3s Arrmas are the most overhyped rc cars in my opinion my Slashpede 4x4 is way more reliable.
 

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I've pretty much given up on my 3s Arrmas, I got sick and tired of having to rebuild the motor and slipper every 3-4 runs. The motor out of my Typhon has been in my Rustler since August and after dozens of runs I haven't even though about checking the motor bearings because I know they aren't packed with dirt. And the Senton is just a big ol pile of crap every time my nephew drives it he breaks something on it. It runs on 2s only with a 15t pinon, he isn't allowed to jump it and you can't run into stuff in a wide open area. The 3s Arrmas are the most overhyped rc cars in my opinion my Slashpede 4x4 is way more reliable.
I'm with you on alot of those down sides. But our senton turned big rock is the only truck that can take a front corner impact from 15 ft onto a concrete skate park and drive away. The kaiju is a close second. Wouldn't even dream of taking my EXB there. So I guess I'll just suffer with buying more arms for now. Maybe I need to get a rival mt10.
 

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The stock ones suck. The RPM ones break for no reason (my 5 year old son has been driving this RC). Is there anything that is worth getting instead?
View attachment 261563 View attachment 261564
Rpm is worse than stock. They flex too much. Breaking shock shafts. Then if you don't flip them in time the break, because eventually they don't rebound back and stay bent. Then they snap over nothing.
Stock are too stiff and rpm are too weak.
Will v2 arms fit the v1 original cassi???
 

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They drive me nuts because of how bad they bow, especially the long ones on the rear. They’re not awful up front but still bow. I don’t think they’re any better than stock arms on durability. It’s not like they last any longer and they still break. Ca get stock arms really cheap off of Jenny’s so prefer that route.
 

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Rpm is worse than stock. They flex too much. Breaking shock shafts. Then if you don't flip them in time the break, because eventually they don't rebound back and stay bent. Then they snap over nothing.
Stock are too stiff and rpm are too weak.
Will v2 arms fit the v1 original cassi???
Yes but you basically need the arms, turnbuckles, camber links, drive shafts, rear hubs, front axle carriers and caster blocks.
 

Hector_Fisher

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They drive me nuts because of how bad they bow, especially the long ones on the rear. They’re not awful up front but still bow. I don’t think they’re any better than stock arms on durability. It’s not like they last any longer and they still break. Ca get stock arms really cheap off of Jenny’s so prefer that route.
How do stock big rock arms hold up? I've only had granite arms which were okay. I imagine longer arms would be worse?
Rpm is worse than stock. They flex too much. Breaking shock shafts. Then if you don't flip them in time the break, because eventually they don't rebound back and stay bent. Then they snap over nothing.
Stock are too stiff and rpm are too weak.
Will v2 arms fit the v1 original cassi???
I've never heard this many issues about other model rpm arms. Buddy had a slashpede that had rpm arms for like 4 years now. Still going strong. Or maybe I just don't get out enough.
 

slick2500

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How do stock big rock arms hold up? I've only had granite arms which were okay. I imagine longer arms would be worse?

I've never heard this many issues about other model rpm arms. Buddy had a slashpede that had rpm arms for like 4 years now. Still going strong. Or maybe I just don't get out enough.
For the 4x4 Slash, Stampede, Rustler ect sadly Rpm makes the best a arms I have used but they still bow. The stock ones are made of glass and the HD arms spilt at the seams. I have not tried the Traxxas Extreme Duty a arms yet though.
Say no to RPM arms
I'm currently in the process of reverting my Outcast back to stock a arms but instead of going with the V1 arms I am going V5 but I forgot to buy new pillow balls and idk if I can screw the og pillow balls into a arms that already had the new style pillow balls in them.
 

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How do stock big rock arms hold up? I've only had granite arms which were okay. I imagine longer arms would be worse?
I’ve had really good luck with them, even when I used to hit the skate park I didn’t have many issues. But I don’t send my cars anymore like so many of y’all do. During my first year in the hobby I realized I prefer ground bashing with occasional jumps over sending it to the moon 🌙
 

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Say no to RPM arms
News to me. Everywhere you go it seems RPM is the snake oil people are screaming about.
For the 4x4 Slash, Stampede, Rustler ect sadly Rpm makes the best a arms I have used but they still bow. The stock ones are made of glass and the HD arms spilt at the seams. I have not tried the Traxxas Extreme Duty a arms yet though.

I'm currently in the process of reverting my Outcast back to stock a arms but instead of going with the V1 arms I am going V5 but I forgot to buy new pillow balls and idk if I can screw the og pillow balls into a arms that already had the new style pillow balls in them.
They may bow, but as long as they don't break, I wouldn't consider that a failure. Just an annoyance, and if it can be solved by occasionally rotating arms, that's a win in my book. The arrma 3s RPM arms breaking are, as I'm sure we can all agree, unacceptable. Coincidentally, i have had good luck with the upper RPM arms for the KEXB. I only swapped over the front upper arms and they are significantly improved over stock. More rigid (ironically) and no more breakages.
I’ve had really good luck with them, even when I used to hit the skate park I didn’t have many issues. But I don’t send my cars anymore like so many of y’all do. During my first year in the hobby I realized I prefer ground bashing with occasional jumps over sending it to the moon 🌙
Unfortunately (I guess?), my big rock is my big sender.

Are the big rock arms reversible, like per side? (doesn't look like it). I hate when companies make arms that only fit on one corner of the truck, seems like a total cash grab. If both options suck, at this point i'm all about which is going to cost the least in the long run. If i break a stock arm on the front corner, I have to buy a whole new set. The RPM arms are reversible, so if I broke a left front I wouldn't need to buy a whole new set for another left front. Jenny's arms shipped are about $18. RPM is about $12 shipped, or $6 per F/R spare. That's a win for the RPM, unfortunately.
 

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News to me. Everywhere you go it seems RPM is the snake oil people are screaming about.

They may bow, but as long as they don't break, I wouldn't consider that a failure. Just an annoyance, and if it can be solved by occasionally rotating arms, that's a win in my book. The arrma 3s RPM arms breaking are, as I'm sure we can all agree, unacceptable. Coincidentally, i have had good luck with the upper RPM arms for the KEXB. I only swapped over the front upper arms and they are significantly improved over stock. More rigid (ironically) and no more breakages.

Unfortunately (I guess?), my big rock is my big sender.

Are the big rock arms reversible, like per side? (doesn't look like it). I hate when companies make arms that only fit on one corner of the truck, seems like a total cash grab. If both options suck, at this point i'm all about which is going to cost the least in the long run. If i break a stock arm on the front corner, I have to buy a whole new set. The RPM arms are reversible, so if I broke a left front I wouldn't need to buy a whole new set for another left front. Jenny's arms shipped are about $18. RPM is about $12 shipped, or $6 per F/R spare. That's a win for the RPM, unfortunately.
So the rpm exb upper arms are an improvement over stock? I've only broken one, my brother has broken one as well(talion exb).. I had the rpm hub carriers for the Xmaxx, fronts are too flexible, rears are ok..
 

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Jenny's arms shipped are about $18. RPM is about $12 shipped, or $6 per F/R spare. That's a win for the RPM, unfortunately.
They’ve gone up a bit. I never order just one thing from Jenny’s. I max out the shipping cost so it doesn’t stress me out too much. I’m glad I got a ton of extra parts when everything was cheaper a couple of years ago.

No the stock arms are not reversible. I know the RPM ones are but when they take the shape of a U literally I had to boil them first to make them able to be switched. And since boiling makes them even more flexible, they would look like an U again after a week.
 

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So the rpm exb upper arms are an improvement over stock? I've only broken one, my brother has broken one as well(talion exb).. I had the rpm hub carriers for the Xmaxx, fronts are too flexible, rears are ok..
In my experience, yes. Based on the rigidity alone. They also get rid of those shims that you use with the stock arms (what basher is looking for that sort of adjustment anyway?) and are much beefier around pin. But like you, i've only broken one (right front i think). the other stock arm is still holding.
 

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Out of curiosity, how do the big rock arms compare to say typhon 6s rears? I'd bet the pivot pins are smaller but nothing a 5/32 drill bit and 4mm pins couldn't remedy..
My bro just bought a 4x2 vorteks boost..he said he's gonna try sticking a Max8 with 4268 into..🤣🤣 I see a pile of stripped parts in his future!! LOL Does the vorteks use the same arms as the big rock? I'm oblivious with regards to the Arrma 3s line.
In my experience, yes. Based on the rigidity alone. They also get rid of those shims that you use with the stock arms (what basher is looking for that sort of adjustment anyway?) and are much beefier around pin. But like you, i've only broken one (right front i think). the other stock arm is still holding.
Mine and my brothers both broke right at the arch near the middle..
My bro is too funny..he literally just handed me a bandit xl-5 in like new condition, along with the stock vxl electrics from a 4x4 rustler..that system would've been perfect for the boost? I'm thankful, but wtf? Max8!? Really?🤣🤣
 
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I’ve had really good luck with them, even when I used to hit the skate park I didn’t have many issues. But I don’t send my cars anymore like so many of y’all do. During my first year in the hobby I realized I prefer ground bashing with occasional jumps over sending it to the moon 🌙
Same here. I have a carbon cub for the air. I'm happy just keeping the truck upright on flat terrain!
 
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