Kraton RPM - Arrma 6s V5 / EXB A-arms!!

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I wonder if boiling the arms you can straighten them out again

It is a thermosetting plastic isn't it?
Yeah I boiled them but they bent again after a few runs.
 
Yeah I boiled them but they bent again after a few runs.
I never had anything go wrong with the stock rear EXB. They are just heavy unsprung weight. But durable. Only the fronts have been an issue for me.
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Well my first run of the year with my krwyon didnt go as planned. It nakes a lawnmower sound in the air and it was bugging me the whole session. Idk what rpm would have done in this case. A one wheel landing in a failed front flip at 40mph. Went tumbling into a a bush of trees aftwerwards
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Arm survived
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I’ve found the stock exb arms to be more than adequate.
Same here. Just replaced a set of rears well over a year old that ovaled out the hinge pin part but never broke.
Well my first run of the year with my krwyon didnt go as planned. It nakes a lawnmower sound in the air and it was bugging me the whole session. Idk what rpm would have done in this case. A one wheel landing in a failed front flip at 40mph. Went tumbling into a a bush of trees aftwerwardsView attachment 217394
Arm survived
View attachment 217395
Just out of curiosity was that lawnmower sound a tire coming unglued?
 
Cracked another EXB upper arm, 4th time same spot, luckily I keep a few extras around

Still waiting for RPM arms from the LHS......

This was on 6s power, MMX8S 1650kv 20t/44t with backflip 6s tires (162mm)

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Let me be real about it RPM arms were fine if you had a stock rig as soon and you M2C Scorched or JBI your rig it was to heavy for them hopping the bigger EXB arms make up for this.
 
Let me be real about it RPM arms were fine if you had a stock rig as soon and you M2C Scorched or JBI your rig it was to heavy for them hopping the bigger EXB arms make up for this.
My rig is very light and mostly titanium and CF now. There few choice m2c parts make it lighter. Scorched parts are all lighter than stock. No jbi parts.

The only difference between this Talion and my ultra lightweight under 7lbs Talion is the 1717 motor
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Even with the big block 1717 I'm only an ounce or two over box stock



This below is the ultra build with all the strongest parts. I ran it like this and kept breaking arms. Now I'm ultra lightweight and still breaking arms


Any more excuses? This is a 2021 EXB model from factory, then fully m2c and HR etc..

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Yeah mine if a talion XL so there is a big chunk of extra weight running the longer chassis and T to T brace. But lets be clear I'm SENDING IT and some times putting the poor thing in local long jump comps so I had to go back to metal towers. Broke two sets of the scorched carbon ones and I'm not saying its the parts fault that's on me. Put an M2C set in a few months back wont be going back for any thing I'm bashing this hard.

Again though its personal choice and yes a lighter rig in all most all regards will brake less need cheaper servos and run cooler with lighter/cheaper electronics.
 
Yeah mine if a talion XL so there is a big chunk of extra weight running the longer chassis and T to T brace. But lets be clear I'm SENDING IT and some times putting the poor thing in local long jump comps so I had to go back to metal towers. Broke two sets of the scorched carbon ones and I'm not saying its the parts fault that's on me. Put an M2C set in a few months back wont be going back for any thing I'm bashing this hard.

Again though its personal choice and yes a lighter rig in all most all regards will brake less need cheaper servos and run cooler with lighter/cheaper electronics.
I'm not really jumping it, not that I don't want to, just I don't have a good spot for it right now (and ramp).

I spend most of my time on a private dirt track. I never break anything racing.

But 6s and big tires break the upper arm at the same spot every time, even without any real crashes
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I'm not really jumping it, not that I don't want to, just I don't have a good spot for it right now (and ramp).

I spend most of my time on a private dirt track. I never break anything racing.

But 6s and big tires break the upper arm at the same spot every time, even without any real crashes
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you mean like this https://gyazo.com/c2d40210d616f8e80dac72474f1ba50c this one cost me front hub, rear a arms, gear housing, hinge pin set and rear chassis brace... landed from a wheelie at about 60 when it broke and car veered to one side and hit the curve hard.
 
I'm not really jumping it, not that I don't want to, just I don't have a good spot for it right now (and ramp).

I spend most of my time on a private dirt track. I never break anything racing.

But 6s and big tires break the upper arm at the same spot every time, even without any real crashes
View attachment 218488
Well, I guess mowing the lawn doesn't take long eh?🤣🍻
Hopefully I don't jinx myself by saying it,but I haven't broken an kexb arm yet? Max6/4092 with backflip MT. No big sends for me but have blasted many a trees..and TRX's 🤣🤣
 
Looks good but by having that open spot where the hinge pins go may cause a lot of flex.
Likely not. When the arm flexes or rotates, most of the stress is going to be on the outer most edges of the pin, the middle will likely only see a little stress. This is why most a-arms don't have much if any meat near the middle of the pin.

Cracked another EXB upper arm, 4th time same spot, luckily I keep a few extras around
I'm mostly interested in the uppers for this same reason. That and I have lots of fwd to aft play in the stock upper arms. The only lower a-arm i ever broke (front) was caused by user error. When you smash two EXBs into each other at 30mph, things tend to break...
 
Yes, definitely! RPM arms rock on 1/10th scale. Too flexy for 1/8th rigs, multiplied by the Kraton arm length. RPM's plastic formula does not scale up very well.
Hell, even on a 1/10 rig the rpm typhon rears droop bad. So bad that I can run short cvds with no issue. But I don’t jump this truck much, it’s my thrash truck. If they were on a car I jumped they’d be worthless So on my other two cars with typhon arms I run stock without issue.

As for the one 10th scale short arms…I have to replace them every 4-6 months or boil and flatten them out. So I don’t buy rpm arms anymore. Once I’m done with them I’ll stick with stock arms off of Jenny’s. Except for this truck, they work on it

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Well, I guess mowing the lawn doesn't take long eh?🤣🍻
Hopefully I don't jinx myself by saying it,but I haven't broken an kexb arm yet? Max6/4092 with backflip MT. No big sends for me but have blasted many a trees..and TRX's 🤣🤣
Well..as always, I had to open my fat mouth!!🤣🤣 Broke an upper arm on the kexb this weekend!! Operator error, tree jumped out in front of me, but frustrating just the same, popped the lower pivot ball on same side so I suppose I should replace the hub as well?
 
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