l just bought a 04 400ex. I ride mostly trails and long backroads. I also hit an occasional jump. I want to make this quad a very fast, relaible, and trail worhty quad. I want to know what is needed to make this happen? Tell me what is ok stock and what is not. Are the stock shocks ok? Skid plates needed? Also what is the biggest bore and stroke i can get and still make the quad relaible? money is not a issue

 

i would definatly get some skids and aftermarket shocks, i am ordering some shocks and then skids next thats for sure. those are the majors, as for the bore, i have no idea.

 

if you want to bore and stroke go with a engine builder,like powroll sparks they put the research into what works with these machines saves a lot of head aches latter.

 

just bought a 04 400ex. I ride mostly trails and long backroads. I also hit an occasional jump. I want to make this quad a very fast, relaible, and trail worhty quad. I want to know what is needed to make this happen? Tell me what is ok stock and what is not. Are the stock shocks ok? Skid plates needed? Also what is the biggest bore and stroke i can get and still make the quad relaible? money is not a issue


Ok, for speed...you could bore it out..I don't know how big you can get..I've seen a lot of 440's though..if you don't want to go bore..then of course find aftermarket header and pipe...k and n filter...remove snorkel or drill holes in the lid to get more airflow...rejet...those are the most common ways to inprove performance...Lighten it up...As for the shocks..thats up to you..if you don't do tons of jumping or mx racing then I would say your stock shocks would be fine...there are better shocks to get but like i said..if its casual jumping and only everynow and then I wouldn't worry about it..at least for now.....as for skid plates....and swing arm and a-arm guards......they are great investments.....are they needed???no....but they protect all of your underbody from getting damaged and it also allows you to slide over rocks, stumps. trees...dune peaks,,,,etc.......with ease...so a great investment there...