I recently purchased a second hand 2006 Ninja 250. The bike ran great for about two weeks (other than an occasional issue cranking which I repaired by replacing the starter motor) until a few days after I changed the oil. After this the bike would have trouble starting even with the choke and would die after 5-10 minutes. Since then I have overhauled the carbs, replaced the fuel line from the carb to petcock, emptied and cleaned the gas tank, replaced the inline fuel filter, and cleaned the airbox and air filter. My most recent fix, overhauling the carb, made it so I can start the bike without choke, but it will only start when starter fluid is sprayed into the carb through the air box or occasionally when the clutch is engaged, kickstand up, and is in first gear. In addition to this the bike still dies after riding a few minutes. I'd appreciate any help I can get.