Hi, Anonymous there is no such thing as a "WEAK SPARK" even though dozens of riders will swear that's what they have and are dying to show you, the bottom line is either you have spark or don't have spark there is nothing in between.
You won't see a dirtbike spark really well, and people only look at it when they have a problem. It is designed to fire under extreme pressure (13:1 compression) and is very robust, but it is not a 1mm bright blue line jumping across a spark plug. It can be white and very hard to see. If you are confident you have weak or no spark prove it by holding the plug in your hand and stark kicking you will be in for a "SHOCKING" surprise!!!!!
60% of these bikes have a flooding issue and/or a fouled plug. 30% need valves adjusted and most of the remaining 10% is something simple in the electrics like a broken kill switch, bad earth on the battery or dead battery, wiring at the steering head damaged or blown fuse.
For more information about your question and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day.
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Honda CR 125R 2002 Sevice Manual
Honda CR125R 2006 Owner Manual