426EX Carb Problems

[HondaRacing23]

NEED DESPRATE HELP PLEASE!!!!

My 426EX isnt running for crap and hasnt been for a long time. I have jetted to the moon and it still wont run for anything. I have 11:1 comp. with JT Racing Piston. HMF full system. Stock carb with a 155 main and a 42 pilot. HMF tells me to use a 180 main but it wont run at all with that. I have tried from stock jetting all the way to a 190 and it wont run right at all. I have change the needle and everything including the air screw. I am about ready to just get a new carb but there kindy spency$$$ but if it fixs my problem i guess ill need to get one. Does anyone know what i can to. any help is greatly appriated. THanks alot...:confused: :confused: :confused: :( :( :(

[Mxracer53]

how long has it been doing this? if u messed any thing with the carb boot snorkel or boost bottle check those and if their any thing in front of the snorkel move it .

[torqen2k1]

I have no problem with my 426. besides the winter I cant get her to start. But im runin a 180 main jet. DynoJet needle in 4th clip position and a 42pilot with 2.75 turns out on fuel mixture screw. If that doesnt wrk check your carb.Check the little $hit that you think that wont affect it. Check to see if you have spark. Check your gaping on your spark plug.

[cals400ex]

i would try around a keihin 155-160 depending if your air box lid is on and if your head is ported. using the stock needle, move the clip to the 4th position from the top. try a 42 pilot jet or so. i would take all of the jets out of the carb first. clean the heck out of the carb with cleaner. then reinstall. make sure both of your intake boots do not have any cracks. look closely. then tighten your carb down fully so you won't have any leaks.

[HondaRacing23]

I am running a 155 or 160 i forget which one i have had it apart so many times. My air box lid is on with a K&N filter. My head is not ported I dont think anyway. I dont know what my shop did I just know they %ucked it up pretty bad. I am running a 42 pilot. where should my air screw be at? Ill check the boots once i get it all apart again.:mad: :mad: ill try this but it might be awile before i post some results im waiting a a bearing carrier and a-arm bearings and busings. once i get all the on ill let you guys know.

[TC426EX]

In what way does it "run like crap"? Does it run at all? Sputter? Die? Low RPM? High RPM? Personally, i ran a 185 in my 426 when I had the stock carb w/o the choke and that seems to be perfect. Plug inspections showed that to be about right. If I took it down to a 180 even or a 175 it turned out to be a little lean colored. Ive ran as high as a 192 in it before with that carb with no problems. Now I got a FCR so my current jetting specs wouldnt help you out at all. If you could maybe post some details of how your bike is running (if at all) that would help out...

[HondaRacing23]

Yes it does run. sometimes it back fires or spits and sputters. I doesnt really die. it runs better on top end then it does in mid and low. I just need to know where i shold have my needle and air screw at and ill try that. Is there any certain GAP that my NGK plus should have? should i use a DPR8Z or a DPR9Z or dont it matter. I heard the the 8Z makes it run cooler but it not needed. let me know...

[cals400ex]

Originally posted by HondaRacing23
Yes it does run. sometimes it back fires or spits and sputters. I doesnt really die. it runs better on top end then it does in mid and low. I just need to know where i shold have my needle and air screw at and ill try that. Is there any certain GAP that my NGK plus should have? should i use a DPR8Z or a DPR9Z or dont it matter. I heard the the 8Z makes it run cooler but it not needed. let me know...

the 9z will make it run cooler, it is a cooler plug. does it backfire on acceleration, deceleration, etc. you are running keihin jets right??

[EXDUNER127]

Mine was doing the same thing this weekend, it was ticking me off because we were at the dunes, i started with a 170 and put the needle in the 4th pos. and i had to move up to a 175, because it was running lean, popping and dying on me out in the dunes when i would hit full throttle, it would get hot and i would have to let it cool down but i had just recently ported my head right before the trip. good luck because i still havent gotten mine running perfect again!