How much abuse can the new 400cc sportquads handle, I mean by suspension and frame. What kinds of jumps can they handle and how hard shouldn't you land them. Also which is the strongest quad for jumping, yfz450 or 450r.

 

I heard about earlier z400 frames and axle's bending or breaking. I think that the yfz has more travel.

 

the yfz has had some motor mount weaknesses, but the frames have been solid. its the best mx bike on the market today. (mainstream). They can handle just about anything an ameature rider can dish out. More than likely you will exceed your limits before you stress the bike. Coming down and crashing is different, even aftermarket parts will bust with the right conditions.

 

Also, which part is usually the part that breaks first from hard or frequent jumps? Axle, swingarm, a-arm, shocks, frame. Have you broken any of these parts from your riding and which part was it?

 

Yah YZF450 would prolly be your best bet jumping. i did here people bustin their A-arms in half, but this is only in cases with jumps like 80 foot doubles, so you should be okay...

 

I would also say the YFZ450

 

YFZ swingarms were originally weak, supposedly they fixed them. I hope so, I saw one broken in half.

Frames will need gusseted to guarantee they don't bend into pretzels on both YFZ and TRX, I'll betcha.