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Honda Guy
10-16-2002, 06:09 PM
Ok heres the deal its for a 400ex btw anyways I took apart the carb one day and pulled out the piliot screw and alot of other stuff when I put it back to geather it dident run right it now dosent really idle right and its fine when ur like drag racing but when the engine down rev's it back fires with and with out the clutch in and then when the engine reaches idle agin it wants to hut off and the only way to keep it from doing all this is to keep on the gas ALL THE TIME. Anyways what do you guys think the problem is engine wise its stock except for a complete trinity pipe k&n air filter and the right main jet
BornOnFire
10-16-2002, 06:23 PM
Sounds like your pilot Jet and Needle need to go up in size.
Honda Guy
10-16-2002, 06:58 PM
see thats the thing it never had this problem untill I took it apart is there somthing i can adjust?
dariusld
10-16-2002, 07:04 PM
How many turns out is the pilot screw or what ever they call that screw?
Honda Guy
10-16-2002, 07:29 PM
I dont now how many thats what i was wondering if it could be anyone know about how many it should be?
Scott400EX
10-16-2002, 07:55 PM
If you have the K&N jet kit it says to turn the pilot screw out 3.5 turns from where it seats min the carb.
Honda Guy
10-16-2002, 08:10 PM
I dont have a jet kit stock jets except for the main
Leo
10-17-2002, 04:35 AM
have you tried adjusting the idle speed?

Leo
Honda Guy
10-17-2002, 02:39 PM
NO but whould that make it back fire?
BornOnFire
10-17-2002, 02:44 PM
My EX was backfiring upon decelleration. I moved the needle clip down one position and it cured it! Seeing that your pilot is still stock, I would bet money that going up one or two sizes will help-based on your mods you listed. I would start there. Go to the dealer and buy two Pilot jets two sizes up from 38 and see what happens.
Honda Guy
10-17-2002, 06:32 PM
How do you adjust the clip?
I never had the problem witht he exact same jetting untill i took the carb apart about how many turns shoul there be on the piliot jet?
dariusld
10-17-2002, 10:22 PM
The pilot SCREW should be 3.5 turns out. Tighten the screw till it seats, not to tight, then turn it 3.5 times. The pilot screw is the one on the very bottom of the carb, it's hard to get to with the carb on.
Honda Guy
10-20-2002, 09:17 AM
so let it get tight then loosen it 3.5 turn?
BornOnFire
10-20-2002, 10:02 AM
Not too tight or you'll damage the seat. Gently close it then back it out. You don't want to damage that seat!
Honda Guy
10-20-2002, 10:35 AM
what happens if you damage the seat?:confused:
atvmbaca
10-20-2002, 11:07 AM
yea, what happens if you damage the pilot screw seat
10-20-2002, 11:59 AM
then you got problems.

so just dont do it
10-20-2002, 02:52 PM
Originally posted by 440EX4me
then you got problems.

so just dont do it

LOL