Er500 misfire problem [Archive] - Kawasaki Motorcycle Forums

Er500 misfire problem

Tony Mountford
06-30-2016, 06:26 PM
Hi I have a problem with a bad misfire and black sooty plug on the left cylinder. I have checked to see if the plug is sparking by pulling the plug cap off and fitting a spare plug into the cap and earthing the plug onto the cylinder barrel. It sparks a small blue spark at the electrode but also a larger yellow spark from the inner insulator . I have swapped the coils over left for right but still have misfire on left side. Bike will start up but is only firing on right side. It has started up on two but after a few minutes the left side begins to misfire then stop firing. When take the plug out it will be black sooty. I have taken off and stripped and cleaned the carb and refitted. It flooded really badly on a short outing the other day had to remove the air filter and housing to clean out the petrol I checked the engine oil for petrol contamination 2.8 litres drained out which is right amount if not removing the oil filter so I gave it 1litre of new oil then topped up with the drained oil , this hasnt happened again since the carb clean. Am thinking It may be a cdi. Problem but am at a loss can anyone shed some light please.

Julius Michael Honrada
07-12-2016, 07:51 AM
i have this exact same issue on my ninja 250 , cylinder #2 is dying only below 2000rpm and have black sooty plug vs the brown plug of the other cylinder , if i set the idle to 2500 it will go back to life , try checking that if that is the case i know i have an engine problem , a ring or a valve because the previous owner had set the timing wrong .

If you rev it will the left cylinder go back to life? Mine goes back to life with no misfire , thats how i know that my cdi aint bad , its only misfiring when below 2000rpm , so i can still use the bike with a high idle rpm , somehow the compression is only leaking when in low rpm but because of valve overlap on midrange rpm , the leak on the valve is irrelevant on higher rpm and the bike will run and accelerate normally though but its very annoying in traffic stops , overheating is always my concern , and high fuel consumption