i want to get a 03 04 z400 and i want to know if the frame problum on the z400 is normal or is it just the racers that have the problum

 

Never had a problem with mine............

 

Unless you ride really hard or do fairly big jumps, you should be okay.

The '03's are the worst for frame weakness. The biggest fault is the upper shock mount.


Even so you can always do what I did and throw a few homeade gussets on!!
'04 FRAME GUSSETED

 

My 03' Z400 has had it's upper shock mounts ripped off 2x. I've re-welded the mounts and have also used a brace I welded from the rear bolt hole to the frame that has really helped. Granted, we were really pushing it w/out having the frame gusseted first. Since the motor is pulled right now for a much needed rebuild I'm in the process of gusseting the frame.

Here's a link that I found that's helpfull. http://www.off-road.com/atv/projects/2003z400/bare/

I'm building my own gusset's from steel I have around, but you can buy them also online. Once the project is complete I'll post picts of the powdercoated frame.

 

Just for the heck of it, here's more of my homeade job:

Layout
GUSSETS1
Flat Iron
GUSSETS2
Shock Tower Gussets
GUSSETS3
Tubes
GUSSETS4

[/b]GUSSETS INSTALLED[/b]

Subframe
GUSSETS5
Stem Mount
GUSSETS6
Shock Tower
GUSSETS7
Flat Iron
GUSSETS8
Front Tubes
GUSSETS9
SRP Mount (Denton Style)
GUSSETS
Bottom Plate
GUSSETS10
Overall
GUSSETS11

 

I've never had a problem with mine the only thing I ever broke on it was ME
and my timing chain

 

BlackKawi400 - looks good! ! ! I'm in the process of doing my at this time. Did you have to bend the tubing you used on the upper shock tower gussets? I use a lowing kit from time to time and if I use tubes to gusset this area my lowering kit would hit... Just wanted to know.....

also.. you didn't add gussets to the lower a-arm pivot points? In other sites I've seen they list this area as a week spot. I don't see any paint chipping on mine so don't see an issue but I thought I'd ask...

I have the same bend in my sub frame as you do... happened when the quad rolled 5x due to catching a rut in 5th gear pinned comming off the straighaway into the first turn..... that's the reason behind the overhaul of my Z...

 

First of all, thanks for the comments s9195!

The upper shock mount tubing is just an extreme angle cut, no bend, you should be able to see it in "gussets3 of the layout pictures. Then the gaps were welded in.

I didn't add any material to the lower a-arm section, but I did finish all the factory welds around the existing ears, and throughout the entire frame. I heard that that was more than adequate. You may be referring to the lower tubes. I added two pieces of tubing on the lower tubes, centered where each of the lower a-arms meet.

I'm not sure exactly what you mean by the subframe bend, the frame isn't bent.

 

well I was wrong with my last post, looking at my bike last night and I found a crack by the oil tank
there went my nice powder coating, as for that its the only crack I have had so far

 

thanks guys i am going to get an 04 z and get the gusset kit just to make shur