Best Free mods for a 400ex

[87Warrior]

anyone have any??

the only ones i know of are
1. grind out the welds in the header pipe
2. take off airbox lid
3. ...

[Nausty]

adjust throttle cable
modify stock slip on
take out choke

[flaneledholes]

Take off the choke, do silencer mods, do burnouts so you can have 19 inch tires for better take-off:D

[flaneledholes]

hey nausty how do you adjust the throttle cable???

[Nausty]

you take off the little rubber peice covering it and unscrew the throtttle cable part where it connects to the throttle cover or whatever you wanna call it. ANyways it is kinda like adjusting the brakes on a bicycle and you have it should barely have any freeplay allowing you to get more fuel to the motor. i hope that made sence.

[MOUSE]

when i adjusted my throttle cable i had a ton of freeplay in it, and boy did it make a difference in it.

i remember when i got the 4oo the guy at the shop told me not to peg it wide open till it was broke in. i didnt know it at the time but there was no way for me to peg it i estimate i was only getting about 3/4 throttle

[Nausty]

yah mine had a ton of freeplay too and it made a HUGE differance I would say like a pipe or something else. its definitely worth every penny:D but it doesn't take more than 5 minutes to do it though either.

airbox lid off
grind welds out of headpipe
gutout spark arrestor
remove choke
adjust throttle cable

now you will have to add a high flow filter and rejet so these arent completely free mods but if you do all this and run it on stock jetting youll be lean and melt a piston and thats really not free!

[flaneledholes]

Nausty is this on the carb or on the thumb-throttle???

[flaneledholes]

anyone know I really want to do this!!! So please anyones response will be greatly appreciated...

[jbirklid]

It's basically like adjusting your clutch pearch. Remove the rubber seal arount the cable on your thumb throttle (on the handlebars) and srcew the cable adjuster out until there is no slack.

Jason...

[flaneledholes]

Thanx sooooooooooo much jason and nausty...

take the baffle out of the pipe.it may sound diff. then drill
bigger holes in every jet. then fidle with the air screw to get the throttle timing right .But never take the airbox lid off and ride.because my friend did and it ruined the carb. dirt built up in the motor and chipped a hugh chunk out of the piston and the sleeve.then try to keep the inside of the carb clean as possible for maxximam performance.

[Lorduss]

when you ajust your throttle you want slack, your trying to get your carb to open all the way, not your thumb throttle, ajust your throttle so when you pin it, with engine off, you can barley hear the carb click, just give it a little more play, otherwise your gonna stretch your cable, you dont want to do that.

About to Drill my Baflle out, i think it will make a differnce.

Originally posted by atvridero8
never take the airbox lid off and ride.because my friend did and it ruined the carb. dirt built up in the motor and chipped a hugh chunk out of the piston and the sleeve.then try to keep the inside of the carb clean as possible for maxximam performance.

this will not happen if you use a qaulity, well maintained filter. I run a oiled UNI high flow with no outerwear and I run with no lid at all and my carb is clean. A K&N will flow more than a UNI but it also may let some fine dirt thru, use an outer wear on a K&N to prevent this.