I have a 2000 model 400ex. The only mods I've done to make it faster is a Pro Circuit T-4 silencer, stock head pipe. Jetted, but I don't remember what size, been 4 years, and K&N filter, with airbox lid still on. And geared up the rear sprocket to a 40 tooth. I've raced MX on this machine for 4 seasons, it is very competitive, and have never so much as taken any bolt off the eng other than to change oil or adjust valves. I'm very impressed with the reliablilty of the Honda eng. Other mods include, +2 +1 A-arms, Works triple rate shocks with rezzy, +2 rpm swingarm, +4 lonestar axle, (if I had it to do over again, I would get a RPM axle) steering stem, beadlock rears with holeshot mx all the way around. Like I said, I've had great luck with this setup, and only get smoked on longer tracks where those big engine quads can stroke on by me in the straights.

 

definately go with a big bore kit i got smoked by a 440ex on alky man that bike was fast it was killing raptors too

 

if it was gutted it probably had the spark arrestor out of it,my dad and i took my spark arrestor out of my dirtbike and it is a WHOLE LOT LOUDER.

 

I had planned on doing a full exhaust over a slip on for looks if nothing else does a full exhaust give performance gains over a slip on?? also which one is recomended? Now since i already have a jet kit will it need re-jetted after the exhaust??? How do i know which Jet kit i have?

 

Yes....full header pipes and silencer do make a big difference over just a slip-on. For instance, Big Gun complete systems are tuned to each component.....the slip-on is tuned to the pipes...which in turn gives you better airflow and higher compression in the flow.

If you ever interested in getting a complete system, e-mail me and I'll hook you up with my budy at John Burr Cycles in CA.

www.honda-yamaha.com

cool...

Joey Mac

 

Spark arrestor?!?!

What's that ?!?! [img]i/expressions/face-icon-small-wink.gif[/img]

 

a gutted pipe may be more than a removed/modified spark arrestor. i gutted my stock one. what you do is take the spark arrestor out and get a big drill bit, most people use 3/4 or 1 inch. look in your pipe where you took the spark arrestor out and you will see a plate down there 4 or 5 inches. this plate has one hole in it from the factory for the exhaust to exit the pipe. you just have to drill a few more holes in it with the drill bit. this does make your exhaust sound a little different when the spark arrestor is out. i gutted mine and left the spark arrestor out and then opened up the air box. i also jetted the bike to a 152. i gained a nice amount of low end to mid range power. top end gains were minimal but you will notice some if its jetted correctly.

 

I have the Big Gun Exhaust and I like it, it made a big difference to me.

 

Wooooooow, there. His quad is probably as fast or faster than a z right now but if he gets a better pipe and tunes and jets it and gears it, don't mean he's goint to beat any z400 he comes across. He'll beat some that he can outride, but some that he might be a better rider than will have a lot more power with the capabilities of a highly modded z and it won't matter if he's better or not the faster bike will win. Maybe you meant any stock z but no way is he going to beat any z even one with a less skilled rider if they have enough mods, peace.

 

stock z, yes
thats pretty simple, right

modded or not