Blue Monkey Trailing arms wooble fix

[french_connection]

I was annoyed at how the blue monkey trailing arms would wooble side to side due to the shock mounting point not being lower than the arms ends...

I went through bunch of search at the shop part bin and came up with this combo.

20141005_135705 by Marc Brassard, on Flickr

Insert them on both side of the end balls and you will have no slop. (On both arm ends)

Also using a longer traxxas ball end on the shock bottom, the one with the stopper on one side seems to be perfect.

20141005_135629 by Marc Brassard, on Flickr

20141005_135622 by Marc Brassard, on Flickr


Hope this helps someone.

[Zukiiholic]

Good to know.
Thanks.

[Powerman]

That is a very nice and cost effective fix. Thanks.

[binaryterror]

Fix? What issue is fixed with this?

You've tightened the joint, removing some of the free-play needed in the system.

[french_connection]

Still lots of free play, just not flip flipping like before... relax until you try it.

[binaryterror]

Can you elaborate on what the issue is and how this helps solve it - that's all I'm trying to learn.

If it moves its fine, its not stopping the shock from working correctly.

You could have just installed the revo rod ends on an angle (one one way, the other the other so they are offset) to remove the twist/turn. I haven't noticed a handling being negatively effected so I haven't changed anything.

[Aebous]

So just to make sure I have this right (I have these links ordered) there was a slight lateral movement? Was it affecting handling or did you just not like it?

[rwkhaussupply]

Daym, You mean I spend over 50$ on a set of alum arms that they cant even build correctly? WTF...

How hard is it to build a correct arm... Uggg.

I havent been able to really drive it since I installed them. And didnt think I had to evaluate their quality / design.

[AWraith build]

They run fine I've had them for a long time now. I do understand what he is saying though.

[allanon1965]

Originally Posted by rwkhaussupply

Daym, You mean I spend over 50$ on a set of alum arms that they cant even build correctly? WTF...

How hard is it to build a correct arm... Uggg.

I havent been able to really drive it since I installed them. And didnt think I had to evaluate their quality / design.

the arms are fine, some dont like the natural side to side rotation of the link end on the ball..all ball design links do this...there is nothing wrong with it nor does it hinder performance in any way.

[french_connection]

The stock arm are perfectly fine and it does not affect the handling, I just hated how they rotated a lot side to side even with all the proper length metal ball ends.

These O-rings only add some light rotational tension so that they do not keep flip flopping clockwise and counter clockwise.

I know you can twist the rod ends in opposite sides to reduce this, but I prefer to keep the rod ends aligned and use O-rings.


If blue monkey drilled the shock hole just a millimetre lower, this would not happen as there would be a downward tension on the arms stopping it from free rolling on itself.

[allanon1965]

I have to disagree, my straight links do this on my wraiths..it has more to do with the natural tendency of the links and arms to rotate on the ball when pivoting... but that is my opinion..on the ones I have (blue monkeys original trailing arm design)

[french_connection]

Originally Posted by allanon1965

I have to disagree, my straight links do this on my wraiths..it has more to do with the natural tendency of the links and arms to rotate on the ball when pivoting... but that is my opinion..on the ones I have (blue monkeys original trailing arm design)

Are the shock mounting point (hole) at the same level as the ball ends or is the hole slightly lower? If its the same design, it will act the same for sure.

its basically a 3 point constraint, if all points align, it rolls, if the middle point is lower, it won't.

[allanon1965]

they are ever so slightly lower...but still rotate

[binaryterror]

Originally Posted by french_connection

its basically a 3 point constraint, if all points align, it rolls, if the middle point is lower, it won't.

Granted this is true, but you technically need the 3rd point to be much lower to prevent any unwanted twist. Barely below will only slightly lessen the tendency of it to twist. At which point you will begin losing clearances under the links to accommodate the lower 3rd point options - or you can go with an open slot style arm to reduce clearance loss and still have lower mounting.

Limiting the roll using o-rings or offset revo ends will reduce free movement when the axle is working to articulate. You might be better off limiting the ball end at the shock with the same o-rings. You'll lessen the twisting but still allow the axle and chassis side rod ends to rotate as needed for articulation and free axle movement.

[bronc4now]

I like it ..and it will keep your balls clean

[rwkhaussupply]

Originally Posted by allanon1965

the arms are fine, some dont like the natural side to side rotation of the link end on the ball..all ball design links do this...there is nothing wrong with it nor does it hinder performance in any way.

A properly designed trailing arm will not do this. If the shock mounting is below the center link of the link ends, then it will not try to rotate (in fact it will prevent it).

It likely does not effect a little RC car. But on a Real 1:1 its a killer of rod ends and shock shafts/ends.