i have a yam. waverun. 91 wr500 start right up, but when you give it gas about 1/3 up engine starts breaking up. i'm sure it elect. but how do i tell which part is the problem? how can i test the pulser. did the check in the manual everything looks good. can anyone help


i just got the ski so hours don't know. it was well taken care of. new gas,compression 136&134,i rebuilt the carb, did all the ohm's test in the manual everything looked good to me. i did put a timing light on each plug just to see, when you get about 1/3 on the gas the spark get wild. i have removed the fly wheel and checked all the wires and that look good also. does not matter if it's in or out of the water. check it after dark looking at the wires don't see any fire coming from them. is there any waay to check the pulse coming from the coil? also opened the electric box everything in there looks clean and good connections. so i guess one of the three coil, cdi, pulser.

[ 01-20-2002: Message edited by: ****hop ]

[ 01-21-2002: Message edited by: ****hop ]

[ 01-21-2002: Message edited by: ****hop ]

Need a lot more info to help. Does it run at WOT? Could be carbs, plugs/plug wires,boots, CDI, bad ground, bad fuel, etc.......... Condition of engine like hours, compression, etc.......

you have 500 or 650 eng ?