MadMan400ex
10-18-2006, 09:10 PM
i recently picked up a 2002 400ex with some mods. i'm not going to list those because they are all gone. i decided to go completely stock with it and picked up an exhaust system, factory spec carb parts, and a new air filter. i also checked the valves and everything is in spec.
so now the problems. i had a 400ex before so i know they're cold blooded but WOW. this thing does not like to start. full choke- crank for 3-5 seconds, fires, then dies after a few seconds. repeat a few times. till it won't fire at all, just cranks over. change the choke to half and same results as full choke. eventually it fires right up but dies after 10-15 seconds with a slight popping/backfire sound. i adjusted the idle up and it seemed to help with the dying but it still has it's problems. i found that the easiest thing to do is fight the full and half choke issues then jump on and ride it. after warm, everthing seems fine and she starts up no problem and without dying. also, applying the throttle before complete warm-up (with no choke) seems to bog it down. the plug (dpr8z) looks decent but not great. a little black from the starting/stopping while using the choke (or so i think).
so is this something i just have to fight or does it seem like something could be wrong. like i said, everything is new stock. except for the used exhaust. but it has new exhaust gaskets and there is no leaks. i also checked for air leaks on the intake boot and it seems to be sealed correctly. am i worried over nothing?
so now the problems. i had a 400ex before so i know they're cold blooded but WOW. this thing does not like to start. full choke- crank for 3-5 seconds, fires, then dies after a few seconds. repeat a few times. till it won't fire at all, just cranks over. change the choke to half and same results as full choke. eventually it fires right up but dies after 10-15 seconds with a slight popping/backfire sound. i adjusted the idle up and it seemed to help with the dying but it still has it's problems. i found that the easiest thing to do is fight the full and half choke issues then jump on and ride it. after warm, everthing seems fine and she starts up no problem and without dying. also, applying the throttle before complete warm-up (with no choke) seems to bog it down. the plug (dpr8z) looks decent but not great. a little black from the starting/stopping while using the choke (or so i think).
so is this something i just have to fight or does it seem like something could be wrong. like i said, everything is new stock. except for the used exhaust. but it has new exhaust gaskets and there is no leaks. i also checked for air leaks on the intake boot and it seems to be sealed correctly. am i worried over nothing?