mods

[Xtremist_02]

I have a 2001 400ex and have been riding quads since i was 10 years old. i mainly ride the tight trails and sandy two tracks up at my cottage and my ride is stock except for razrs b/c the stock tires popped in canada. I seldomly ride the dunes and once a year make a journey to canada to ride the roads and logging trails. I wondered if anyone could recommend a pipe and filter? i have heard many different opinions of many different pipes but i wanted some first hand opinions from people who ride similar terrain as I. Also do i need a new header pipe if im not going to modify the motor a whole lot?. one last thing, what kind of power increases will i find? thanks alot for your time.

[flaneledholes]

I dont think you will need a new header unless motor work is done... It will really help if you tell us where you want your power to"hit" the most???

[Xtremist_02]

i think bottom end and midrange, and that way i can gear up a tooth on my countershaft sprocket with out bogging down. what do you think?

[TravEX]

go with a 14T front sprocket, White Bros E series pipe, K&N Filter and jet kit,,,then, you will feel a difference in you 400,,,later, Trav

[Xtremist_02]

since i live in michigan and the climate changes so often here am i gong to have troubles with the jetting in the winter vs. the summer? i know this problem plagues 2-strokes, but this is my first four-stroke and my knowledge of them is limited.

[TravEX]

if you get the K&N jet kit, it will cover all that in the instructions, and the main jet is easy to change,,,

[Xtremist_02]

where in the powerband do your mods help out the best?

[TravEX]

i know this doesn't answer your Q, but throughout on mine,,,all around it is a lot stronger,,,there are alot of guys on here from around your area that will be able to help ya out alot,,,how much you looking to spend for your mods?

[Xtremist_02]

um probably like 400$$ or so. for now anyways. i have limited income and a jeep im fixing up too so the funds arent the best. i definitly want a slip on and a new filter but im not sure what else to do

[R-Crazy]

If you are woried about jetting, there is a thing called a Dial-a-Jet that allows you tune your air-fuel mixture with the turn of a knob. check it out. I dont have the site, but I am sure somebody does. i think it was around 70 bucks.

dave

[Xtremist_02]

thanks i never thought of that, although i have heard of it. i was just wondering if anyone from michigan had any problems with their machines jetting when it gets really cold out so i didnt have to mess around with the dial-a-jet kit.

[flaneledholes]

My suggestion to you is that you get a hmf slipon for bottom to midrange power... All I have to say bout the white brothers, is that I havent come agross a 400 with a cocky rider on it with a wb and I have never fallen short of being able to beat him by 2 quad lengths... Hmf is the best bottom end slip-on available, I can clutch the 400 and make the front wheels fly up!!!! JMO tho.... :square

[Xtremist_02]

anyone else have anything posotive or negative to say about any other slip ons? does anyone think i should just get a complete system or would it be a waste since my motor has no work done to it?

[Xtremist_02]

just curious what do you mean by ground the welds off your headpipe?

[Sportrax10]

u should get a uni-airfilter and a K&N air filter..... use the K&N when ur riding in the sand, and use the Uni when your rinding in te dirt.

[Xtremist_02]

couldnt i just get one of them?
like a k&n w/ a prefilter? that would eliminate some cost and just the hassle of changing my air filter for the two or three times a year i ride at the dunes. so should i just get an uni?