Kraton RPM A-Arms vs. Aluminum

cordell12

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After much admiring of aluminum A-arms I have decided to order RPM for both the front and rear. Neither are broke, and I know deep down I shouldn't replace them until needed, but I feel like I needed something to do to my Kraton. Working on it is just as fun as driving for me, I find it relaxing and since I don't get into TV much it works out for me. Anyway, did I make the right choice by choosing RPM over Aluminum? My choice wasnt so much with the cost as it was durability. Plastic can take a hit, flex and return to shape. Aluminum can take that same hit, bend or twist ever so slightly and cause a issue with steering for example. Or am I overthinking this?
 

KRA-TON7

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Well I installed RPM on the front and rear of my Kraton, they have lived up to all the great reviews I read about RPM. I installed GPM front and rear on my Big Rock, and they have been just as durable,, haven't flexed at all, nor have any of the many Hot Racing alloy upgrades I have installed on both of my rigs. I plan to get silver GPM'S for the Kraken in the near future just haven't had the xtra cash to let go of on this
 

cordell12

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There is a guy on FaceBook from Australia who has fairly good prices and will ship to wherever you are.

https://www.facebook.com/markhordesigns/

No website, have to contact him via messenger but it seems legit. I like the tower to tower carbon fiber brace he makes for various RC, including the Kraton.

I was also looking at GPM but found a few threads were they are getting bashed pretty hard due to using weaker aluminium. Perhaps these are just biased reviews, or the part took a direct hit from 30+ feet lol.
 

WoodiE

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Anyway, did I make the right choice by choosing RPM over Aluminum? My choice wasnt so much with the cost as it was durability. Plastic can take a hit, flex and return to shape. Aluminum can take that same hit, bend or twist ever so slightly and cause a issue with steering for example. Or am I overthinking this?
Yes you made the right choice for all the reasons you've already pointed out.

RPM a-arms are a tank and much cheaper than aluminum arms. Aluminum doesn't bend very easy which means that impact/shock is transferred else where (typically most costly or time consuming fixes). If the aluminum does bend then you pretty much go buy a new expensive a-arm. Aluminum weakens as it bends, so bending it back just further weakens it.

RPM is covered by a life time warranty, so if you do manage to bust one they will replace it for free. I have yet to find a single aluminum a-arm that comes with this same type of warranty.

You made a great choice!
 

s14tat

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Aluminum has its place, but suspension arms are not one of them. Basically aluminum makes great support pieces as long as they don't come into contact with anything during a collision.
 

Paultro84

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After much admiring of aluminum A-arms I have decided to order RPM for both the front and rear. Neither are broke, and I know deep down I shouldn't replace them until needed, but I feel like I needed something to do to my Kraton. Working on it is just as fun as driving for me, I find it relaxing and since I don't get into TV much it works out for me. Anyway, did I make the right choice by choosing RPM over Aluminum? My choice wasnt so much with the cost as it was durability. Plastic can take a hit, flex and return to shape. Aluminum can take that same hit, bend or twist ever so slightly and cause a issue with steering for example. Or am I overthinking this?

I've only broke front A arms and replaced them with RPM. No problems at all. Kevin Talbot on YouTube recommended spraying the plastic arms with WD-40 and letting it soak in over night and it allows the plastic to bend a little more. Seems to work good.
 

KRA-TON7

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Man, I don't understand how anyone can knock RPM, so what if they are made in China, I have bought no telling how many things over the years that were made in China . I have GPM shock towers, front and rear, have slammed them in the ground many many times and they are straight .I also have GPM turnbuckles on all 4 corners along with the servo arm they give you also in the set that mounts to the servo horn . I plan on getting front and rear diff housings and I want 2 sets of their rear shocks, I like running longer on the front, gives you much more tuning, and I am going to get there UPGRADED spring steel axles for all 4 wheels cause the factory ARRMA ones bend too easy and I can't do anything but praise their products, I have many and all were just as nice as the Hot Racing mods I have as well. It's your decision of course, but I can't say anything bad about RPM either, I have cartwheeled it so many times I have yet to brake one, plus they are cheaper and work just fine. I just want some for looks mainly
 

cordell12

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You must be thinking of someone else. RPM RC Products are not made in China, they are made in the USA.

I think he meant to type "GPM", or maybe not, just re-read it.

Either way it looks like I made the right choice!
 

RCROD

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Cordell, you made the right choice going with composite suspension arms instead of aluminum. I also agree with most comments here on this thread. Aluminum has it's place, and suspension arms is not one of them, as there needs to be some flex, and A-arms is one of the best places to have this flex. Furthermore, aluminum arms would add a lot unnecessary weight.

However, I got spare Arrma suspension arms from the car breakers, as the prices were just too good. I may try and boil these spare arms for more durability and flex.

I do have RPM arms on my AE Rival MT and quite happy with them. You have to like their replacement warranty, as this is hard to beat. However, my one concern with using RPM arms on Arrma vehicles is their design around the hinge pin area. All their Arrma arms, including the lower front, upper front and rear arms look like they have no composite material around the middle part that covers the hinge pins. It looks like a good portion of the hinge pins are exposed to the elements. Although the front upper hinge pins are ok, the stock lower hinge pins already rust way too easily, and I wonder if this RPM design will make it even worst?
 

Ahlwardt9

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After much admiring of aluminum A-arms I have decided to order RPM for both the front and rear. Neither are broke, and I know deep down I shouldn't replace them until needed, but I feel like I needed something to do to my Kraton. Working on it is just as fun as driving for me, I find it relaxing and since I don't get into TV much it works out for me. Anyway, did I make the right choice by choosing RPM over Aluminum? My choice wasnt so much with the cost as it was durability. Plastic can take a hit, flex and return to shape. Aluminum can take that same hit, bend or twist ever so slightly and cause a issue with steering for example. Or am I overthinking this?
I’ve had aluminum and rpm a arms on my nitro slash. I’ve bent even snapped the aluminum a arm. The rpm a arm I installed took a similar hit as the aluminum ones and held up great with no issues
 

RCROD

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I’ve had aluminum and rpm a arms on my nitro slash. I’ve bent even snapped the aluminum a arm. The rpm a arm I installed took a similar hit as the aluminum ones and held up great with no issues
Makes sense. You need some give in the suspension arms and aluminum arms do not flex enough. Suspension arms take a beating and this is one place you need some of that flex/give. The composite material RPM uses has even more flex than the stock arms, and one of the biggest reasons why they usually work well. Boiling the stock arms or any spares you may have usually helps add a bit more flex, and makes them even more durable, which is another good option.

Besides your stock suspension arms, boiling should also help make your wing mounts, chassis braces, wheels, etc, more durable.
 
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