Join Date: Jun 2010
Location: Sweetwater, Texas US
Running Poorly, All Speeds
Bike will not idle below 2500 RPM
Sometimes runs great but will cut out as if running on one cyclinder.
Top end rebuilt at the bike shop in Huntsville Alabama. They said is was due to lower compression in one cyclinder. Engine slightly bored as they installed new pistons and rings.
Still ran like poorly above 5000 RPM.
All gaskets and hoses in the carb replaced. Most other parts replaced as well. Have verified float height at 17mm and tried up and down from there by 1mm with no difference on performance.
Drained and refilled the tank numerous times. Inspected the carb for cleanliness during every assembly. New plugs, even tried hotter plugs.
Sometimes it will run great for weeks but if I push it to full throttle, it starts missing. Tried larger and smaller main jets, no difference.
1990 Ninja 250R, stock except for the K&N filters and the top end rebuild.
Any Ideas? I have inspected everything electrical that I can put a meter on.