Originally Posted by
Afun
I for one was not able to keep those 91mm in the outdrives when having an awkward landing. It happened several times. Then I jumped on here for advice. Pitpop was one of the ones who said to run the 93mm in the front. According to him Cody is also running them. It's been fine ever since. The only thing I could blame is the flex of the chassis especially on awkward landings for the 91mm to pop out. I also did not shim those 91mm. Maybe I should have, but I just followed the manual instructions.
Don't get me wrong. I am not being negative. This car has made me super fast. I just need to tweak things a little differently because I do not have the aptitude of a pro. That's the entire reason for getting the Agama mounts and not suffering DNF's for not checking those little screws on the plates.
I hope that makes sense.
The 91mm outdrives popping out was a big talking point and most everyone settled on using 93mm up front. The primary reason for them popping out would be droop setting (or amount of suspension travel), arm flex, steering angles, how the outdrive and diff were shimmed, some combo of all the above. But chassis flex would have little to do with them popping out.
The chassis flex is dominated by two modes of deformation. First bending (think of bending the chassis into a "U" shape. And second torsion (think of twisting the chassis like wringing out a towel). Neither of these types of deformations would be the dominant cause of the outdrive popping out.