my buddy has a 03 honda 400ex. it currently in the shop getting a 440 big bore, stage 2 hot cam, jetting, and port and polishing the head. it also has yoshi RS3 full exhaust and k&n filter.

will it be able to beat a 450??

 

Nope! There is a replacement for displacement and it is engine design, and that is not even taking into account that the 450's are all considerably lighter than the EX.

Even though you can get that old school EX engine only 10cc's less than the 450's, it is still a low RPM air cooled old school design. On the other hand, the 450's have light little slipper pistons, they rev to the moon, and more important they make their power at high rpm....long after that old school engines have fallen off the curve.....

The EX engine lugs down nicely, which makes it a superb trail quad....and on the trail is where it belongs.

 

its all on the driver too. and you have to put lots of money and time into it as well. i have an address and cash for anyone with a 450 that can beat my 426ex, and ill let my mom race it!! a 440 will for sure bet a 450...but it still falls back on $$$$. only reason i have so much money tied up in mine, is cuz i sold my soul to the devil for a bad bike!!! lol!!!! good luck.

 

<div class="FTQUOTE"><begin quote>Originally posted by: go-hard-or-go-home

its all on the driver too. and you have to put lots of money and time into it as well. i have an address and cash for anyone with a 450 that can beat my 426ex, and ill let my mom race it!! a 440 will for sure bet a 450...but it still falls back on $$$$. only reason i have so much money tied up in mine, is cuz i sold my soul to the devil for a bad bike!!! lol!!!! good luck.</end quote></div>


so what else besides what he has done already, would he have to do to embarass a 450 owner?

oh he also has +2 extended a arms and axle....

 

like i said...$$$$. i have a 426 13:1 compression with a big dome. Ported and polished head. 3 angle valve job. Shortened valve guides. Titanium kimblewhite valves. Went from a like 222 or 232 lift in the cam to a 483 lift, by web cams. Thats like a stage 6 to hotcam. Hard face rockers. very heavy duty valve springs. Stroked the crank 2mm. Shaved the transmission gears to mesh perfect, meaning i never miss a gear. NEVER!!! they jus stick together. Went 2 teeth up in the front, and down 4 in the back. Now you going arnt you suposed to go down in the front and up in the back?...nope, just the oppisite because of the power and transmission. dayntech cdi. Big gun pipe (full). 2 12v batterys. No-toil filter (screw k&n, unless you ride street) edlebrock carb........


so much more as well. but see what i mean as far as money to beat a 450. a 450 with a aftermarket pipe and jet will be about the same as my bike. and i have put a lot of time of effort to make this a good bike that will last!! i dont know too much more i can do to this bike engine wise. i do know that if you do this to a 450, well you better hold on!!

 

seems i ran into the same problem....just with cars.....when there is nothing left to bore or stroke and you have the best heads/cam/intake for your combo........time for some forced induction[img]i/expressions/face-icon-small-smile.gif[/img] Nitrous/turbo/supercharger.......now thats how you make some HP!! I see N.O.S. makes a small cheater system for a 400ex for about $600.00 could be interesting.......