Well without my wifes permission I bought a brand new 400ex about a month ago. Since then I have been putting all kinds of mods on it. I started with Tusk nerfs as I didnt like my toes just hanging down there. Then I put an HMF slip-on exhaust and with that I bought a dynajet kit to rejet it with and a UNI Filter. Then I put a CFM aluminum airbox on it to house the filter, battery and all the electronics. I put a Doug Eichner Edelbrock carb on it last night (its the 440 carb and it took allot of tuning but I think I got it right but cannot get it to open all the way as the cable it too long). I have ordered the Curtis Sparks timing key for it and his CDI, it should be here next week. Mind you all this has been done in a months time and my wife would kill me if she knew how much I have spent on it.

I guess my only concern is that I dont want to do anything to make the quad less reliable. Let me know what you all think.

I love this thing and cant wait to get it up to the dunes this summer.

Thanks, Micah.

 

congrats on the new bike. you musta found a great deal on a leftover i suppose...your mods are good. you really didnt need the carb or cdi. the stock carb is plenty big for a stock engine. and the 400 runs out of *** before it hits the stock rev limit, making the cdi box really useless, especially for the price of the carb and cdi. a nice set of tires,skids and a bumper woulda been money well spent! the 400 is a great bike tho, i enjoy spending time with mine! good luck

 

i believe the timing advance key will make it run hotter

 

I had an Edelbrock on the 400 once. I live right near the factory, and I went over there and their tech guys installed and tuned it for me (so don't say I didn't know what I was doing!). It never was right, no matter what we tried! Always had a bog off the bottom, that would not go away. One day it bogged on a takeoff and make me I come up short on a big double jump, so next day I pulled it off and tossed the thing!!!

 

Yeah I have seen this post in numerous threads but I have had two Edelbrocks now and loved them both. Much better carb then stock as far as tunability.

 

I assued that would be the case...but first hand experience proved it wrong!

 

I originally bought an edelbrock for my wr400f. As soon as I put it on and started the bike I loved it. The only reason I bought this one is because it was cheap and I dont have to rejet it like the normal carb. The only issue I have with the carb is the fact that I cannot get it to open all the way. It lacks about an 1/8" in the thumb throttle for it to completely open but since its made for the 440 it opens plenty enough for the standard bore 400.

 

Boy we think a like, it is a lot easier to ask for forgiveness than permission. I not running them down by anymeans but I had a sparks timing advanced key in and it sheared off during my 3rd break in cycle. Kinda made a mess because new to 4 strokes It took me a while to figure it out. Glad to hear about the Eldelbrock that most all like them. I have one coming, if someone could give me a little advice on what or how I should set it up as far as jetting and such. I should say it has only a slip on and is 12:1 piston in it with a stage 2 cam.