Hi Guys
I have just scored an old trx 300 from a neighbour. It was sitting under a tree in his yard for a few years so to say its a little rough is an understatement. I have had it running but it only goes for a short time. It is definitely an electrical problem but I am having trouble tracking it down. After it runs for a few minutes it stops, when I hit the starter if fires once but thats all. If I turn the key off and on it will fire once only and not start. When I remove the spark plug and hit the starter there is one spark and only one spark. I have tried to find the problem and after cleaning terminals and wiggling wires it gets a consistant spark and starts and runs well then all of a sudden it stops again and the same old problem arises. I go through all the wiring and all of a sudden it will get a consistant spark for no apparent reason. This has happened about 6 to 8 times and I have no idea where this problem is coming from. The wiring is old and has been patched up a bit over the years so I am trying to clean that up also. If someone has a wiring diagram they could email me it would be fantastic and would make my mission a whole lot easier. Any advice would be greatly appreciated. Kind Regards Coopers

 

ok what year is it. Sounds like a cdi box problem. if it is a 96 there was a update on cdi boxs.

 

Sorry - I am not sure what year it is but I assume its sometime in the late 80's

 

ok, well this is what I would do, get a new plug, the cdi box is under the front plastic, two connectors going into it. try to squeeze it and see if it will start or tap it on the frame. on the left side of the motor there are some connectors on the bottom, oil temp, netraul, and revrse the neutral and revrse are together and labeled, unplug the revrse one, maybe switch sorted to ground.