I have a 2003 white z400 with a Yoshimura slip-on and I am getting beat by a 2002 honda 400ex with a wb r4 slip-on, thats not right. I am going to put a big bore kit in it, but I just cant decide which one to go with CT, Trinity, LRD I just cant decide.

Does anyone have any suggestions on what to do????

 

Ok..either he is a better rider than you, or you have the pipe jetted incorrectly. I'm not bashing on the 400ex, but this should not happen. You do not need a big bore for this, just a little tunuing or a little more shifting practice. But, if you are going to get the big bore...how much money are you willing on spending?? That will give us an idea on what you want.

 

Ive been riding four 6 years now so I dont think its the shifting. The 400ex beats me only in top end i can flat leave him 1st through 4th but when im in 5th wide open he starts to pull on me and eventually he passes me. I had the pipe and jetting done by the dealer and he told me that he put a 170 in it is that correct?? as far as big bore kits wanting to spend about 1200.00 to 1500.00 if possible.

 

I was also wondering about gearing it up a little form the stock14-40 to maybe 14-41 or 42. i know i will lose some low end but do you think that would help?

 

you have your gearing backwards if you want it faster top speed you need a smaller rear sprocket and with the yoshi slip on your airbox lid off and a k&n with outerwears you should only b at 1 155 main if you want a big bore check out thumper racing i will tell you i dont get beat very often and not by another 4 stroke yet not to say it wont happen

 

the 14/41-42 will take away top end and give mor bottom. I would start with new CDI and Cams from Yosh and Edelbrock carb

 

adrenjnky,
hows that big bore treating you? what have you reaced soo far....lets see a review PLEAAAAASE

 

TC racing! Tom can help you with a great motor.
Of the ones you listed,,LRD would be the only one to touch my motor!!!!!
tcracingengines.com [img]i/expressions/face-icon-small-smile.gif[/img]

 

well i took it out for the first time last saterday to sandlake its scary fast i only was beat by 2 banshees i beat raptors several a preditor which seem very fast stock and a few piped banshees i need a longer swing arm to leave harder it stands up and you have to let out of it a little in sec and third i will b down at winchester bay friday threw monday then to stanthony the rest of the week so that will b the reall test

 

How are you about to get beat by a Honda 400EX.....and to get the best bore kit.....your best bet would be with Duncan Racing.....they make a 470 bore kit! Kicks ***.......