ChitownRC

I have a Mugen MBX-4 buggy that at full compression on the front suspension (like landing off a jump) the front CVD pin pulls out of the drive cup at the diff and the axle comes out. It's almost like the drive cup is in too far or the axle is too short. At ride height the pin sits 1/16th in from the edge of the cup. Most others I've seen sit towards the center of the cup. The only way I can keep them in is by setting the stops so low that it limits travel. The pillow balls are in as close as possible without binding at full lock. Any ideas here as to what the problem might be??

Sounds like its got the wrong length CVD in there.

Is it a CVD, or Dogbone???? If it is a dogbone, you can do a temp fix, by putting a short (1/16") piece of fuel tubing in the drivecups at both ends. This will keep the dogbone from sliding all the way in on either side.

It's a CVD....I thought it may have been replaced with shorter ones but I compared it to new ones from a MBX-5 and they are the same length. (assuming 4 & 5 CVD's are the same to begin with)

Adjust your droop set screws, they should be on the lower arm just about where the arms starts to go over the chassis.

I already did that...and to get them to stop dropping out of the cups my travel is severly limited.

The odd thing is that on the other MBX4 ( J/T Truggy) the CvD pins are almost centered in the cups F & R where as on the buggy they are only about 1/16th of an inch from the edge of the cup.

where is your camber set at?

Could the the CVD's you have in the car be MBX5's and MBX4's are longer ?

I picked up a set of CVDs for a MBX5 and compared them...they are the same length, although the dia. is smaller on the 5's. The drive cups carried over from the 4 to the 5 (same part #)

camber is at -3.5 deg

Here's a couple of close pics...with the stops set in far enough to retain the cvds they contact the frame with about 1/4 inch of clearance from chassis to ground. But they will flex untill it bottoms the chassis and then they are prone to pop out. Looking from the front of the car the right side is usually the one that comes out.

click for closer look...


full compression...


at rest...




How much travel should a buggy have?? With the stops set I have about 5/8" of travel from ride height to bottom(on stops)

What is your camber at?

His camber is set at -3.5 George.
So that's a MBX4 with MBX5 CVD's ?

If you bought it used, maybe someone put MBX5 CVD's in it and those are too short for some reason.

Obsessive R/C Wrote:I picked up a set of CVDs for a MBX5 and compared them...they are the same length

As I said they are the same length...I have both and checked just to be sure.

:confused:

Sorry missed the camber, Isnt 3.5 to low. Try setting it at -1 and see if it still does it.

I just found this...http://www.carolinasrc.com/webstore/Scri...roduct=157

What do you think??

Sorry about that. Misread the sentence.

No problem, I appreciate all the help.