i need to know some stuff about re-jettin. i have a K&N air filter and a White Bros E-Series muffler. if i take the lid off the airbox, will i need re-jettin? if i do need to, is there kits to buy or wut? im srry, i know this is a stunting forum, but yall are the only ATV guys i know. thanks!

 

it should be rejetted even if the airbox is on.. if its off i think youll be fine

just do a chop test to be sure

ps.. are u stuntin this .. if so stock is best

 

wut is a chop test? and yes i stunt this but i also drag race. my goal is to hit 100MPH + on this bike, so any extra power i can git helps.

 

run the machine in like 2nd across a field with the throttle wide open .. hit the kill switch and release the throttle at the same time

pull the plug and check the color ...
white = lean
black = rich

as for hitting a 100 .. u should have bought a frame and stuffed a bike motor in it..

 

you dont think the 400 can get there? i went 78 with the stock filter on. now i have the K&N and am plannin on buyin a 40mm carb (if i can fing one) and port and polish. if i cant get 100 by then, idk wut ill do.

 

im not thinking yer getting 78 with a filter bro .. maybe a big bore and other serious mods

top speed on an 05 KFX is like 65 (per atv sport mag)

 

the only mod it had on when i did that was a White Bros Exhaust system, gutted. but my friend followed me in his car.

 

and the atv mags tested their quads on a short dirt track. i was on a 2 mile long stretch of concrete

 

the review i read didnt state where they did the hi speed run

but ill tell ya that ive ridden evry sport quad out except a dvx and a KFX wil will not go over 70 with a pipe and jet kit

 

well my friend said i went 78, so maybe he's lyin. i need to git a speedo anyway.

 

I don't know about white bros. but most exhaust companies have their own jet kits or they can at least let you know what kind of tuning is required with their products. I'd call them and find out.

 

I think that any quad going that fast would eventually cause a serious injury to its owner. I've ridden a few modded 250r's. the new 450's, z's and ex's. They all get super squirrelly above 50.

Be careful bro!

 

Our two 450Rs don't do 100 and they have: big bores over 50cc's, new valves, cams, carbon pro exaust, jetted race carbs, race clutches, and are geared 2 teeth off front and five up on back and still only about 95 and that requires a stabalizer arm and steering dampaner cause you'll be all over otherwise, non the less rock on wit yer stunting :YEAH