I ride trails and long roads.

Basic Mods. Race exhaust, high flow air filter and jet kit.

What would be the rwhp of each with mods?

Which would have more low end torque?

Top speeds? at rev limit and/or with 1 tooth larger front sprocket if needed.

 

z400 would be a bit better in every catagory and also responds to mods a bit better imo

 

reverse is nice. But I don't need it.
Liquid cooling has its ups and downs.
I could give up the extra's on a KFX/Z for a frame that don't crack.

Hearing about people's KFX/Z 400 frames cracking is the only thing turning me away from them machines.

 

suzuki will fix that !don't worry. they had weak axles and they fixed it

 

yes that makes sence... buy it!!! suzuki will have it for 3 months and fix it dont worry...

or, you can just buy a 400EX and be done with it.

 

No probs with my frame , or any other issues .

rwhp :
400EX with WB R-4 exhaust , K&N kit , 14t frt spkt , and CDI box = 28.6 hp on 20in maxxis razrs

KFX 400 with CT racing exhaust , K&N kit ,and 13t frt spkt = 29.9 hp on maxxis razr 2's

Top end we are dead even , on the trails it depends on which one of us ate our wheaties , drag race I smoke him everytime , Dunes drag race with the same kind of paddles mostly I have 1 or 2 quad length win. It takes
a CDI box to be even at top end but I have more torq and pull through the gears most faster , could be sprockets
but both of us went one tooth down from stock. The HP readings seem low but 28 and 29 are pretty damn good considering dynoed on dirt tires , mine was dynoed on 8in Hoosiers also and had around a 38.4

400EX's are great bikes and very reliable , but I love my KFX even tho I am a guinne pig and next years will be perfect. just my .02

 

go with the EX......proven reliability, and great performance for trails.

 

I OWN BOTH, so I speak from experience. Why even consider the EX?? The Z is the next step up in the evolutionary process (liquid cooled, double overhead cams, reverse, etc.). Gusset the frame if you need to. My Z has seen a lot of hard a$$ desert miles, with no problems. I like the bike more, every time I ride it. Honda will never give us a new 450/650 bike as long as they can keep selling people 400's. Become part of the solution, not part of the problem!