Sick0
01-26-2004, 11:23 PM
my 400ex is missing real bad on the topend( anything over half throttle). I've been dealing with this problem since I blow a head gasket in august after having a 440 kit installed about a month before. I hate to say it but I rode a while with a blow head gasket (about a week) just try to mess with jetting not really know what was wrong with it. Well I finally came to the concusion it was my head gasket. So put a new head gasket in, and set did the same thing. I messed with diffrent jetting, tryed to carbs. Both of witch I had set real good for my set up right before the I blow the head gasket, so I know I had to be close on jetting. I tryed running a diffrent exhaused, cheacking for air leaks. I gave up and open the motor up again. I looked close at the piston and look like one of the exhause valves came contact with piston. I thinks from theblow head gasket. The was barely hit the piston and the valve looked good. But I thought maybe I burn up the rings and damage the cycinder from riding on it with a blow head gasket. So installed a diffrent cyclinder with a fresh piston.
well the problem is still happening. The motors sounds pretty good until it starts to warm up and then it will start to choke. I also notice( i could be wrong) smoke when its does this. So I'm geussing this probly some thing to do with the valves. But I barrowed a friends cdi box and coils and going to try them to atleast rule that out. Has this happen to anybody else and /or does anybody have a clue what the problem is.
well the problem is still happening. The motors sounds pretty good until it starts to warm up and then it will start to choke. I also notice( i could be wrong) smoke when its does this. So I'm geussing this probly some thing to do with the valves. But I barrowed a friends cdi box and coils and going to try them to atleast rule that out. Has this happen to anybody else and /or does anybody have a clue what the problem is.