will i have any problems breakin the frame in a z400 after jumping high? i heard the frame sucks or the atv jumps niceE?

 

Depends on how high your jumping also the landing will play a factor. Anything over 4 feet will most likely fully compress your stock suspension which will effect the problem areas. This also depends on your weight too.

I have added a Arens frame brace and changed the suspension, and I have had no probs.

 

My 03 has given me no problems, after two seasons of hard a$$ desert riding. But, rumor is that the later frames were beefed up??? And, the 05 gets a bunch of upgrades, so it's a no brainer, get an 05.

 

how many costs the frame upgrade?

 

You can send the frame to Lonestar and they'll gusset and powdercoat it for $600. Or you can buy the gusset kit for around $150 I think and weld it on yourself.

 

If you know a welder, you can buy the gusset kit for about $55 and have someone weld it on for you. Do a search in the forums for gusset kit or frame problems. There's tons of information in here.