My buddy has a 84 honda shadow vt700 bike. It stalled out on him while he was riding it and it's been giving him problems since then. It wouldn't start, so we jump start it, and it ran, but turned it off and tried to start it again and it didn't want to start. Spark plugs dont seem to be getting a spark, battery reads on a dmm while trying to start the bike at a 8v to 9v. Once we stop trying it goes back to 12.6v, it'll almost start and itll backfire; whats the problem here? Brand new battery and brand new spark plugs. Ground has been cleaned, Corrosion free.