Re: \'91 phazer trouble
Does it go up to about 4000-5000 rpm and just bog?? and then eventually clear up and run fine? If so you might have a grounding problem on the engine. Some Yamaha sleds ground their block to the frame through the engine mounts, and after awhile the ground gets crappy.
Try running a seperate ground wire from the chassis directly to the coil, to the CDI unit. This should most likely fix your problem.
Uzi... Yamaha Sleds, Honda Bikes, and Ford Trucks