Bowed Out Front Tires When Compressed?

[HPI-Killer]

This is in my Revo build but not everyone goes into the build threads so I will post it here.


I recently went to a 3.3 chassis and RPM arms all around, now with the new tires and wheels (original .15 MAXX combo) when I set the rig on all four adnd press down on it, the front wheels bow outward from each other like \-o-/ .
What would make it do this? I also have some no name alloy front knuckles on it, maybe I have the steering links on the wrong side of the knuckle where the links attach?

If it makes it easier I can post pics.

Thanks guys

 

[RevoJoe]

Its basically an impossibility to get the linkages wrong. The linkages are like molex plugs. They will only assemble one way...

Sounds like the top control arms are too long, or back to front. Make sure you havent mixed the top ones with the bottom ones, and make sure the leading edges are facing the right way.

Looking at the suspension on mine now.... can't see anything else that could cause positive camber.

Keep in mind though, if the front tyres maintain grip, and don't slide outwards, the front suspension will push the front wheels into a positive camber.

 

[Lessen]

The only thing not clear is you didn't state what direction they are bowing from each other. Are you getting positive camber like RevoJoe is suspecting or are you getting toe out? If toe out is the case then fundamentally what is happening is that under compression, the absolute X distance from steering rack to the knuckle is becoming significantly shorter. This used to be a common assembly mistake on some models as one could easily connect the tie rod to the wrong side of the knuckles' assembly point. On the Revo it's pretty straight forward where things go.

 

[HPI-Killer]

the front of the tires bow away from each other, stand still its alright, but I'm not sure what camber is but I dont know anything beyond slapping the RPM parts on...

 

[Lessen]

OK, that's what I expected. Looking at the blow-up images of assembly your tie-rods should mount between a pair of ears on both the knuckle and the steering rack. On other vehicles the rod only attaches to one side of a single ear and sometimes folks put it on the wrong side which creates what is called bump-steer (what you are seeing). I'm not that familiar with the Revo unfortunately but you have a bump-steer issue

 

[Snook Man]

I’ve already replied to your build thread and told you the solution.