Notorious RPM Rear A-Arm Shattered

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bicketybam

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Arrma RC's
  1. BigRock 4x4
  2. Granite
  3. Infraction
  4. Kraton 8S
  5. Kraton 6s
  6. Kraton 4s
  7. Mojave
  8. Notorious
  9. Talion
  10. Typhon 6s
I have to say....I'm really pissed off about this. I took my Notorious to the BMX track along with my Typhon and Granite. I ran the Notorious first and was going nice and easy. Truth be told, I'm afraid of trashing the body so I wasn't really sending it like I usually so. After landing a small jump (on all 4 wheels no less) I saw the back end of the truck dragging. I went over and saw that the rear RPM A-arm simply shatteted.

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To compound the matter, the breakage caused collateral damage. The lower hinge pin bent and the shock post sheared off. I also lost the dogbone.

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I am going to put the unused stock rear A-arms back on. I had everything in hand to fix this except the hinge pins which I just ordered.

I'll be the first to admit when I ball up a truck and break something. I'm an ok driver at best and I have no problem admitting it. But this was just a plain failure of the RPM A-Arm. It will make me think long and hard if I go back to them again.
 
Wow I can't believe that.

I thought their stuff was softer than that.

If you have to buy new shock mounts I would look into these tekno mounts you need a 5/32 drill bit I think.

 
Wow I can't believe that.

I thought their stuff was softer than that.

If you have to buy new shock mounts I would look into these tekno mounts you need a 5/32 drill bit I think.


I ran the same arms on my Kraton from July until last week and had some pretty nasty landings. They never broke. They ended up warping from use but they never shattered like this. As far as the shock mount goes, I have 8 extra that I stock. So I'm good.
 
Dang man. I've never seen RPM a-arms do that.

When I upgrade my stock a-arms to RPM on any RC I always buy one extra set as well. That way in the event I ever need to use their warranty I have an extra for back up.

I'm not even going to bother to send it in for warranty. I'm more pissed about the bent hinge pin and lost dogbone.
 
I've broken tons of Rpm parts but not from normal landings.
I agree with @Nitr0EngiEx said about the Tekno shock mounts I went through 3 or 4 sets of the stock 3mm shock mount bolts before I got fed up with them, but I also went with Tekno shocks at the same time 4mm shafts vs 3.5mm shafts it was a no brainer which was going to be better. Use a 4mm drill bit to drill out the holes. I cringed when I drilled out my rear Voltage tower.
This is another benefit to running cvds in the rear, never loose a dog bone again.
 
I've broken tons of Rpm parts but not from normal landings.
I agree with @Nitr0EngiEx said about the Tekno shock mounts I went through 3 or 4 sets of the stock 3mm shock mount bolts before I got fed up with them, but I also went with Tekno shocks at the same time 4mm shafts vs 3.5mm shafts it was a no brainer which was going to be better. Use a 4mm drill bit to drill out the holes. I cringed when I drilled out my rear Voltage tower.
This is another benefit to running cvds in the rear, never loose a dog bone again.

I’ve only broken one other shock mount and that was when I took my Kraton to the BMX track for the first time. My driving was awful, lol. I’ve also only bent two shock shafts. I just discovered I used a front shock shaft on the rear shock by mistake. When I was tearing down my Kraton for cleaning/inspection, I lined up all my shocks. To my surprise I had two fronts, one "middle" and one rear ? I had been driving it that way for 2 months. Whoops!
 
Challenge accepted. Landed on a bird bath, also bent a Tekno 4mm shock shaft.
View attachment 23680
At least you could get that out easy, when the stock ones bend then you almost have to cut them off because they wont unthread.

which shock towers do you have? What I found is that my stock towers like to bend and are soft. do you have 7075 ?
 
At least you could get that out easy, when the stock ones bend then you almost have to cut them off because they wont unthread.

which shock towers do you have? What I found is that my stock towers like to bend and are soft. do you have 7075 ?
It's still the stock tower in front and yeah it is pretty tweaked. Have the Voltage Racing shock tower in the rear and it's held up great so far. Gonna get a Voltage tower for the front soon. Might pm him and see if he would make one with the shock mounts already drilled to 4mm.
 
I have to say....I'm really pissed off about this. I took my Notorious to the BMX track along with my Typhon and Granite. I ran the Notorious first and was going nice and easy. Truth be told, I'm afraid of trashing the body so I wasn't really sending it like I usually so. After landing a small jump (on all 4 wheels no less) I saw the back end of the truck dragging. I went over and saw that the rear RPM A-arm simply shatteted.

View attachment 23642View attachment 23643View attachment 23645View attachment 23646

To compound the matter, the breakage caused collateral damage. The lower hinge pin bent and the shock post sheared off. I also lost the dogbone.

View attachment 23648
View attachment 23649

I am going to put the unused stock rear A-arms back on. I had everything in hand to fix this except the hinge pins which I just ordered.

I'll be the first to admit when I ball up a truck and break something. I'm an ok driver at best and I have no problem admitting it. But this was just a plain failure of the RPM A-Arm. It will make me think long and hard if I go back to them again.
Installed the same arms yesterday on my notorious. 1 jump today and it broke in exactly the same way. Big jump soft landing that the stock arms took 100x and never broke. Went with rpm as the fitment is better with no slop but it shatterd like glass. Very upset with rpm. Will be sending mine in for replacement. If we all send them in with same issue maybe they will adress the problem.
 

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I wonder if they recently changed their plastic compound or if there was just a bad batch? I've bent some RPM arms into a 'U' shape with heavy abuse, but I've NEVER had one break.
 
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