Interesting read guys. Lots of useful information. I also have one of these 1989 moto 4 350 quads. I bought it back in 1997 and have had nothing but good luck with it until now. Like they say, all good things must end😂. Mine stills starts right up and idles fine but you can’t go past a 1/4 throttle or it starts cutting out like it’s missing on one cylinder but it only has one cylinder. Lol The majority of the time it sits in the barn and is mainly used during hunting season. It still gets me in and out of the woods but isn’t much help getting my deer out. I have taken the carb off and went through it cleaning everything, replaced the coil, spark plug and cdi. (eBay actually had one) it does run a little better but still the same issue. I also checked to make sure it’s charging and it’s around 13.2 volts. I am an ase certified mechanic (22years) on cars and heavy trucks but know little about these things and information is limited to what I can find online. If anyone has any ideas on this issue I’d be greatly appreciate it if you would share. Lol. Thanks