Hi Guys, I'm based in Norfolk UK, have a MC19 1989, runs well ,until now, has suddenly decided not to start, turns over ,try's to run but just backfires, any clues for me before i start taking bike to bits, thanks
Spark, fuel, air, compression. These bikes are known for their electrical components failing. I mean the bikes almost 40 years old! Try checking the stator, regular/rec, had to replace my regulator, Put thermal paste on the new one to the frame for better thermal dissipation, that usually goes on these. As well as check spark strength, might not be igniting properly. Check spark plugs, ignition coils, these bikes have 2 with each one powering 2 plugs. Might need to clean air box while your at it. Give carbies a deep clean and recalibration with proper equipment, 4 vac. Hopefully compression is all good, if not, good luck finding a new motor. Maybe put a cb400sf engine in it, unlock the rev limiter a bit, stiffer valve springs.
Hopefully it’s all good now and your riding it to the redline .
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