I need a big bore kit for my Z

[Rollin94Bronco]

I have a z400 and i would like to kno about good bolt on kits.. anything over 450 and some prices.. i appreciate it

[AceLtz]

What mods do you have right now?

[Rollin94Bronco]

peformance wise i just have a yoshi exhuast and k&n filter and jets

[IrideMHSC]

I dunno whats considered "bolt on" but i consider it anything you dont have to tear the engine down for and can litterally just bolt on. but if its an actuall bolt on an edelbrock carb will gain you some horses.. or if you want to actually bore out your motor iv had real good luck with my Thumper Racing 470 kit.

[Rollin94Bronco]

when i say bolt on i mean the whole kit head piston everything.. so i have bigger water jackets and everything i dont want to mess around with boring because my cousin has the 440 which was bore and all it does is overheat

[Rollin94Bronco]

i would also appreciate some more info on the 470 kit sounds like a good size

[450r51]

get the yoshi 450 kit, very impressive. this kit puts the wombing on my 450r every now and then.:devil:

[Rollin94Bronco]

can i get some info on these kits? price place to get them all info is appreciated

[450r51]

u can get the yoshi kit right from the yoshimura website....or go to your dealer, they might be able to get it for u

[AceLtz]

Ok first of all. A big bore kit will do nothing for you if you still have your stock carb and cams. You will feel a much bigger increase in power by stepping up to hotcams and a fcr39.

Your engine components are made for 400ccs. By upping the ccs your not going to get much gain because your cams are made to run 400ccs and your carb is meant to feed 400ccs. Your cam lobes wont be able to let the enging ework to its full potential. NEither will the carb. Once you get a good set of aftermarket cams and a carb then you can look into big bore kits.

After cams and carb. There are many big bore kits available. heres a list with disadvantages/ advantages.

Athena 434: Good price ($550-$650), Great power, LArger water jackets, Great customer service, best off all it comes with a whole new cylinder so you can keep your stock bore as a spare.

Wiseco 440: inexpensive ($200 or so), youll still need to get your cylinder bored out, Because the sleeve is steel it has a different heating/cooling temp. than your aluminum cylinder which is not good.

There are also many companies such as sparks, yoshimura, dasa, lukes, tudors, 4stroketech..... that offer thier big bore kits. Theyre a little more expensive but overall theyre all great motors. Bost of these kits come complete with cams, porting and a cdi. Carb you usually have to buy seperate.

remember, a motor is only as good as the components that complement it.

[Tri-valleyracin]

with all that power u need to get suspention too cuse it wont handle at all and the stock stuff wont take the extra power.

[IrideMHSC]

I agree with ace... i have the 470 kit but not the aftermarket carbs and cams... you can still feel a huge difference inbetween a stocker and my bike but im not sure of the diff in my bike and someone with the cams and etc.... the 470 that i have came from thumper racing and can be rather pricey if i remember right but youd just have to check the sight... no matter what i seriously reccomend the nickasil coating on your sleeve no matter what... it will save you alot of trouble in the long run.

[dads400ex]

Here is what you need. :D
http://www.exriders.com/vbb/showthread.php?s=&threadid=200511