i got a miss in my motor how to go about fixing it?

[ranger400ex1994]

my motor misses at 1/4 or 1/2 throttle or even just at ideal. but when i go past that it wont miss at all. when ever i pull my plug out it is always black and it seems like it really got worse this winter becasue it seems like i was fouling a plug every time i rode it. i think it is just the spark plug connector. its the yellow plug that goes on the head of the spark plug. when the moto is running i hold i tight on the plug and puch it up and it wont miss at all. and whenever i pull off the plug the top of the spark plug is always bent. does this sound like my problem? also can i just buy that pice or do i need the hole wireing and everything?

[cals400ex]

first off, get a new plug and make sure the choke isn't on.

[ranger400ex1994]

well the choke is off and i have changed the plug about 4 or 5 time sence i have owned the quad.

[Atreyu]

Originally posted by Atreyu
Could be many things. The smoking could be because of rings, the ticking because of valves.


Secondly, the loss of power could be a carb thing. Follow your throttle line to the carb and make sure it is straight. If this is not the case then your going to have to take off your plastics, airbox, and gas tank. Remove the golden plate from the top of the carb. once you do this there will be a long pin in there. Press on your throttle and see if the throttle body is reacting to this. If not then this "long pin" came unscrewed causing the lack of midrange. If the throttle body will not go up, no gas will get through. You mus unnattatch (sp?) the arm and find the two screws that hold the plate in place. Screw them back in and see if the throttle body lifts by pressing the throttle, then put it back together. Hope that helped. ;)