[cjford717]

I have a 1992 yamaha 500 waverunner. It will idle perfect, but it will throttle up to about 1/2 throttle and then it will begin to cutout, a rev limiter of some sort will engage. I rebuilt the carb, put in new plugs, checked compression and still no change. Can someone please help me with my problem. Thank You.

 

[cjford717]

could it be the cdi?

 

[atc250r]

Is it overheating? There is a sensor that will have the ignition box limit the RPM to about 2500 if it senses an overheat condition. I am battling an overheat problem with my 1990 WR 650 and that is exactly what it does when it gets hot. Mine ran fine for the last two days then this afternoon it started overheating on me. I started a thread about it over in the Yamaha section, you might want to keep an eye on it. The sensor can be bypassed but if you have a genuine overheat condition then you're just going to blow the motor up by riding it with that bypassed.

John