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Old 05-20-2012, 10:23 PM
young grease monkey young grease monkey is offline
Motorized Bicycle Elite Member
Join Date: Sep 2011
Location: Chicago
Posts: 362
Default Re: Im new at this and I am looking for help...

See if the spark plug cap came off. The top of the engine is called the cylinder head, and that is where the combustion happens. The spark plug ignites the fuel air mix, and without a spark the engine won't run. The spark plug is what makes a spark, as the name might suggest. Just Google "spark plug" to see what it looks like, I can't post pictures from my phone. There is a black cap that goes on the spark plug, and it carries the high voltage electricity the the spark plug to make a spark. Make sure it is connected good. The little black box that the cap is connected to by a wire is the CDI, and what it does is take low voltage from the engine magneto and turn it into high voltage so it makes a strong spark. The wires that connect the cdi to the engine must be connected well, blue wire to blue wire and black to black. The white wire is for accessories, so it should be taped up if not being used. If it touches any metal on the bike, it will short circuit and then you will not have a spark, or a weak spark at best. There are also wires that go to the kill button to stop the engine, all they do is short circuit so the engine stops making a spark. It doesn't matter how they are connected as long as one wire connects to the black wire and one goes to the blue wire. An easy way to make sure you are getting a spark is to unscrew the spark plug with a wrench, counterclockwise to loosen it, and put the cap on then turn the engine by turning the pedals with the wheel off the ground and the clutch lever out. The spark plug has to be touching part of the engine to make an electrical connection for the spark. Don't worry about eletricuting yourself, it is very low power even though it is high volts, all it can do is give a little jolt but no harm. Hope you get it fixed soon to enjoy this nice riding weather!
some people say that a motorbike defeats the purpose of a bike. i tell them to get a flintstone's car.
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