I just finished tuning and performing complete maintenance on a 1997 Badger 80. Quite similar to the Grizzly 80, I believe.
Original carb was oxidizing and pitted on the inside. Despite my best efforts at cleaning, rebuilding and trying to smooth out the pitting, the carb would never run quite right. Finally gave up and ordered the cheap Chinese copy on eBay. For $ 40 it was worth a try.
New carb was an excellent copy and the bike ran better then ever, once I got it started. Cold starts were still a problem. Bike would not start or run with the choke even slightly opened. Ran smooth once warmed up, but would not idle without constant throttle input or idle screw turned in too far.
While installing a 7" led light bar on the Badger, I realized that the charging system was not up to the task. Charged at 13.3 volts at full throttle but dropped to 12.7v when the light was turned on. Light requires very little juice to operate. Stator was functioning but not very well.
So I replaced the stator and rectifier with parts from RMStator - great folks to deal with. I asked a question via email and they had a tech call me with a response - outstanding service. I also cleanedand greased every electrical connection and ground on the bike. Tested every component according to service manual. Charging was now between 13.4v and 14v at full throttle. Only drops .1 when light is turned on. Don't expect much output from the stator at idle. It only has 1 charging coil.
To my surprise, the bike ran better than ever. I assume that the spark was stronger due to the new source coil.
See pic.
I set the intake valve to recommended .003 and exhaust at .005. Bike now idled great - like a new bike!! Cold starts and choke still were a problem though. Very difficult to start. Choke off, throttle wide open and lots of cranking required to cold start. Again, once started - ran like a top!
After more reading and researching. I went back to the valves. Went with .005 and .005.
Hit the start switch and it roared to life! Choke now operates properly. The bike starts and idles without touching the throttle. 1st time in 8 years that ever happened. I was able to back out the idle screw a half turn from its previous spot to obtain a perfect idle at normal temp.
I hope something from my experience helps someone.