my guess would be a defect. which is why AE gave you a new chassis. they dont replace every chassis that breaks.

Wrong, There is a servo, likely a transponder, the shocks, shock tower, wheels, tires & foams, A-arms, act. It all adds up and when any mass is moving it's inertial mass increases significantly. For instance, when you jog, upwards of 3 times your own body weight is exerted on your hips than when you walk or run fast/sprint. (I happen to know this because I've had a hip replacement for 26+ years)

So, if a 4.2's front end normally weighs say 12oz, when landing jumps you have to multiply its weight quite a few times being as not only is it coming down, but there is usually a good amount of speed to factor in as well which multiplies that figure even further.

In other words, Yes way those fractures can happen that way.

Looking at how the fracture is also not very clean, it suggests they cracked from stress exactly as I'm describing. In the 2nd picture in particular you can see how the composite fibers were pulled apart which would suggest the chassis flexed outwardly until it cracked.

if it would be a bad landing it would be in a much thinner place. it would not be braking two tall vertical walls.

and there using so much fibers in the chassis it makes it very crisp and brittle.
in the new chassis the fibers are very concentrated in the sides and i can feel the surface is not "plastic smooth". the fibers are actually exposed there.

I have both e T4.1 FT and a 4.2 and there is no difference in how the chassis are made. they are virtually identical in terms of material and fabrication.

This picture literally suggests outward flex as I described it because that's what the pulled apart fibers depict.

https://lh4.googleusercontent.com/-P...255B1%255D.JPG

It's not the worst thing in the world as we all smash our whips from time to time and it's a miracle this doesn't happen with greater frequency.
This chassis might have also been defective but it doesn't look like it.

I broken more then a few chassis the same way...

Hit a cinder block, walls , pipes way hard.

Never once thought any of those chassis were defective though.:)

I hear ya' on that one. No replacement for a defective driver :lol:

I enjoy the SCT class. But buggy has got my attention now.
Any must do modifications for assembly? I check out the beginning of thus thread and saw the brace shaved down, anything else.
I dont have the time to read 500 pages of posts! lol

I run on a high bite indoor smooth clay track. its got everything big jumps, small ones, switch backs, straight and sweeper!

Hideeho
The box setup is actually a good starting point for most any dirt track. The only thing that needs attention or upgrading out of the box is the ball cups. With 1 vocal exception, the box ball cups are universally shunned because they bend & break easily. If you put them on, expect 1-2 to break the 1st time out.

There are, of course, tons of hop up parts out there, but none of them are needed to be able to win with this buggy.

Ball cups a must. Fix the shock issue so you don't have metal on metal (easy fix with SC10 plastic bushings) and you are golden.

Run the box set up and go from there. Shocks will be first that you play with. You don't even need to go the shaved u-brace route. We race high bite indoor smooth clay and the factory guy there runs box set up with some shock adjustments on track changes.

Have fun, best car out there straight out of the box.

What is the "brace shave" good for, I have seen it done before and was wondering what it helps!!

So then the B4.2 comes with the B44 arms? My car came with arms that have 2 sway bar ball mounts.

I'm sure I'll be corrected if I'm wrong, but shaving the brace essentially lowers the inner pivot ball stud, which in turn raises the roll center and thus reduces the rear grip. I believe this is done to re-balance the chassis and gain more steering (so, to reduce push).

Question:

What's the benefit of running grey carbon front arm and black plastic rear arms over the B4.2 kit arms? I've seen some guys at our indoor track running the black plastic rears.

Thx

As far as I can tell from various explanation, you are correct. The shaved U--brace wit C hubs are for high bite, mostly indoor tracks where as a non shaved U-brace and A hubs are for an out door track.

Ok, sounds legit!! I don't think that is anything I wanna look into doing then, because I need my rear traction:D