thinking about putting my stock 400ex carb back on

[MEOFF]

i have been trying to put the 05 450r carb on my 400ex what a pain in the butt.i cant get it to run right the plug wont hold a color and it gets super hot now really fast ive changed main jets moved the needle position and still wont run right.put the hrc needle in it and everything gone up to a 210 main it dies out with that in it.its ported 11:1 piston stage 1 hot cam rev kit k&n slip on pipe. i have had to clean the filter out because it gets to much fuel and it goes into the air box,i have checked for leaks by spraying starting fluid around it and it acts fine so i really have no idea what to do with it now i just want to ride my quad but i think that carb is the worst thing i have done to my quad so im thinking about getting rid of it

[#484]

Check the float level. It sounds like it may be set to high and letting to much fuel into the bowl. That could be the cause of the poor running and the fuel going into the air box and filter.

[Stickman400]

You did properly plug the hotstart right?

[MEOFF]

Yes hot start is plugged right I have had the carb apart several times cleaned it completely it just gets old like I said this is the worst mod I have ever done to my quad

[DragonGunner]

Wheres your air mixture screw setting....didn't see a mention of that, a turn in or out can make a big differance.

[Pittsburgh400ex]

Your throttle cable working properly? If its short it will hold your float up. If i recall correctly a 400 cable doesnt work. Aside from that, was this a new carb with ALL PARTS on it? Not calling you dumb or anything, just it could be missing something you dont even know needs to be there.

[Pittsburgh400ex]

Also, is it sucking air anywhere? That wouldnt explain an airbox of gas, but check the intake boots for rips.

[MEOFF]

It was used had the wrong needle in it when I got it so I put the hrc needle in it I have sprayed everything down with starting fluid and it didn't rev any higher I have the the fuel screw from 1 1/2 turns out to 3 1/2 and I can't get it to work right and I have the 450 plus 2 inch throttle cable on it I did take the white plastic piece that goes on the main jet out don't think that would make any difference

[CJM]

You need that white piece that goes into the bowl.

Did you install the needle right?

if your gonna get rid of it, Ill buy the HRC needle off ya.

[MEOFF]

Can anyone tell me what the purpose of that white plastic piece is in the bowl maybe I will put that back in and see what that does where should I put the fuel screw

[CJM]

Fuel screw 2.5 turns out from bottomed. The white piece holds the float in place if I recall.

[hocman123]

yea i belive the plastic part keeps the floats from going to high and flooding the bowl.

what kind of bore do u have in it 210 sounds crazy high unless u have a 440 and even then it sounds high. also what size pilot jet do u have in it the 450 use bigger pilot jets u should have at least a 50 proberly a 52 pilot with the mods u have

[Stickman400]

I've got a 210 in mine with the mods in my sig. I went all the way up to a 220 and it still didn't sputter.

[MEOFF]

It has the stock bore just 11:1 piston it studered with the 210 in it I got a 50 pilot jet in it right now it runs better with a smaller main but it still ain't right guess I should put that plastic piece back in and see if that changes anything

[Stickman400]

I'd prolly run a 175 in yours and a 52 pilot and see how it works.

[hocman123]

i have a 407 with closed lid and run a 165 in my 450 carb

but i agree with stickman400 u should be more in the range 165-175 maybe more maybe less depending on ur mods. what jet did u have in the 400 carb? generally it dosnt move a ton at least on the bikes i have done this mod on. I was running a 158 in my 400 carb