I am looking for more out of my z-400, it is a lot of fun but I am a guy that needs more. I am not looking for a switch to a differant machine, I have ridden them all except the new yamaha 450 and I like the ride and feel of the z the best for me. I am very impressed with the power thus far and I am looking into more. Currently I have a K&N filter, air box lid removed, pro flows in the air box (a snowmobile mod) Full yosh comp exhaust, and stage 2 hotcams and a -1 front sprocket. If you ever ride the st. anthony dunes I can lug up all hills (choke cherry, middle bowl, devils dune) in 2nd gear rapped but cannot pull third I weigh 225lbs. I am looking into the yosh 450 kit or possibly even going with a 470. The 470 I have seen is only a bore kit (97mm piston) so it scares me a bit but I am hoping to use the yosh modded crank +5mm with a 92 or 94 high compression piston. Also I am looking into adding the Edelbrock carb (38mm) or even a carb off a predator (42mm) I am looking for any info on people that have any of these mods or have done them. How do you like the edelbrock carb? My local shop took a predator to a 580, cracked the cylinder, and did it 3 times before deciding the kit was crap and putting a stock cylinder back on. I don't care to keep redoing it so I need to know everything. Also do any of you know of a higher performance radiator for the LTZ that will keep a bigger motor cool enough to run the dunes all day. My buddy weighs 130 lbs and has a 440 kit in his suzuki and I need to beat him.[img]i/expressions/face-icon-small-wink.gif[/img]

 

Four stoke Tech can has a 500 kit.

 

Four stoke Tech can
WHAT???
what does teh can stand for???

 

I have about the same mods on my z, minus the hot cams. I rode a Yosh 450, with the 92mm piston, 5mm offset crank pin, 41FCR, full yosh SYStem, This thing hauls, I think that is good way to go. The local shop whos bike it was, said they could do the whole thing for about 2200 inc the carb, porting,polishing, ect. exhaust us extra.
Go for it.

 

Four stroke tech web site does not work, did they move it? Is the kit just a bore or do you stroke it also?

Do you think the yosh 450 is large enough or should I do a 94mm piston with the stroked crank, and a carb and port/polish?

 

I have nothing to compare it to, but that 450 hauled the mail. I would leave the 92mm, and you can always go bigger in the bore later. Do the same with compression.

 

I think I'd go with the 450 kit also, of course you have to wath it the higher you go the less reliable your z will become. I'm sure you know that but I'm just a chicken when it comes to tinkering with my engine, which I don't do since I really just know how to change oil and ajust the chain. If I ever do go bigger I will probably get the 450 kit and have a buddy help me with it. Good luck.

 

I know that Steve Beilman has been testing a Alba Suzuki z400 race bike with a 500 kit in it. Once they got a rev limiter that allowed the beast to rev higher it was an awesone sight to behold. It rips!