Need some help

[Killakawi]

let me start out by saying i have no performance upgrades to my kfx400. all that has been done, was tag bars, skids, rear grab bar, and handlebar bracket. i want to buy a used stock motor for this bike, and build it up (big bore, cams, polish etc) on a stock bike am i stupid for this w/o suspension, wider a-arms etc??? Any suggestion, and criticism appreciated.

[jonboy]

If you can afford to buy an extra engine to build go for it. But you may want to consider the suspension first. If you can get the power that you have to the ground in a controlled manner you may be able to run faster than you think. If it is not hooking up in the corners or not able to handle the power behind bigger jumps,etc. What good is it to have all the power. Just my $.02

[Killakawi]

yea that is why i asked, i dont even no y i want to do this, i have all the power i need already, but i jsut want that extra to be able to wip the back out much easier on tight turns, and get some more top end. maybe this is the man in me jsut needing more power, haha, also i used to b a boat mechanic, want to widen my horizons and dip into this, the only way ur goin to learn is to do it rite???

engine wise, any suggestion on bore kits, or cams, or anything little or big things i can do???

[alaskaZ]

honeslty i would go with some suspension first it make a world of a difference aarms,shocks,axle, as for more power try a 13 tooth sprocket engine wise do all the bolt ons as in filter,jetting,exhaust and mayby a bigger carb that alone will wake up your z alot then if your still not satisfied go ahaed and build her up.

[indyZrider]

yep! suspension-suspension-suspension!!!!!! as for the motor, you dont need a big bore to get more power. the ltz engine is a detuned drz engine. lower revs, compression, intake and exhaust. the difference between a stock Z and a piped, jetted and intaked Z is night and day. you will wonder why you didnt do it earlier. you dont need a bigger carb unless you big bore. just open your stock carb up. its like this, just an example, the carb and intake and exhaust can all handle the rate of 100. but because of environmentalists and tree huggers and all that they have to detune them for pollution and all that crap. so your stock Z is running at like 40. thats why they put the brass plug over the mixture screw so you cant adjust it. dude you just need to open it up more. give it more air, gas and exhaust capabilities and you will love it! and its cheaper and more reliable than some of the big bore kits.

[Killakawi]

indyZrider, can you expand more on opening the carb up, i have no problem with mechanical, but im scared of tweeking the carb, i have no idea what im doing when it comes to messing with air/fuel mixtures

[indyZrider]

if you go to z400central you can find detailed pics. you have to jet bigger and get an adjustable needle, and you have to drill out the brass plug to get to the air/fuel mix screw. its easier to adjust if you buy a 15 dollar adjustable fuel screw. put a bigger pilot jet in there, either a 25 or a 27.5. the stock one is 22.5. this will let your carb breathe better. bigger main jets, bigger pilot jets and the right adjustment on the screw will do you some good. i have an hmf s/o, a k&n intake, an ehs lid, and my carb is set with a 160 main jet, 25 pilot jet, 3 turns out on the screw and on the 3rd slot on the needle. then its time for the butt dyno. trial and error. or if you want to spend the money get it dynoed at the dealer. remember leaner is meaner but only if you dont mind rebuilding your engine alot. make it a little rich and youll be good to go. good luck