Hi all new to forms, Have a problem with my boys 04 sportsman 90. Spark is very weak, I can feel a spark from the coil wire when I hold my hand on it but it is not very strong at all. I appreciate the help[img]i/expressions/face-icon-small-sad.gif[/img]

 

I'm no expert but I have had a similar problem with my sons dirtbike and fourwheeler. The first thing I would do is change the plug. Then check the wiring if that doesn't work. My sons dirtbike used to foul plugs alot, like sometimes after just an hour of riding cause he putted around to much, I changed the main jet to the next size smaller and that solved the problem for the most part. On his old fourwheeler I was chasing down an ignition problem because of weak or no spark and found a wire connection that was just slightely loose which was causing it to run good sometimes and not at all at others. Good luck.

 

My daughter has a 03 Sportsman 90 and it had the same issue, I just changed the plug and it fixed the problem, there is another post about fouling plug on a pred 90 that you may want to look at.. I just went to advanced auto and purchased some autolite plugs, keeping 2 spairs in the tool box at all times.. ...

NGK BP7HS or BPR7HS
Autolight 4123
Champion 8814-1

 

Ours was a connection problem in the spark plug wire - where it connects to the 90 degree bend at the spark plug socket.