Yamaha Grizzly ATV Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Bought a used Grizzly 80 from a dealer that appeared to be in great shape. The carb was a problem from almost day one. After removing it for cleaning I could never get it adjusted properly. It would not come back to idle quickly, but would hang up and after 20 to 30 seconds it would return to idle. I checked all the linkage and cable and confirmed that it was all working properly. Went back into the carb to make sure it was spotlessly clean, assembled properly and the slide and needle were moving freely. Same problem, so I ordered a new carb, installed it and all issues were resolved. Then my son got some really bad gas which gummed up the carb. After cleaning the carb–complete disassembly–I am having some of the same problems I had with the original carb. So, it appears to me that the problem is probably with getting the carb adjusted. The pilot screw–under the security cap– was opened about 1/2 turn originally and that’s where I reset it. I can’t seem to find the right combination to get it to run right. I’ve done a number of carbs on other bikes and never had this problem. Any ideas or suggestions will be appreciated.
 

·
Registered
Joined
·
31 Posts
Our little Grizzly 125 does this when it's cold outside, if you push the throttle it hangs for a little bit, but once it's warmed up it seems fine, I'd like to know how to resolve it though as it is a bit frustrating.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
With larger bikes that I have worked on it has usually been a linkage problem or an air leak around the intake or throttle shaft seals. Air leaks are easily located by using some propane around the carb and intake at idle. If if speeds up you have found the leak. I have determined that the cables are operating fine and I'm going to check with propane one more time before possibly removing the carb again. I can usually find mechanical issues, it's electrical issues that I'm at a loss over. The valves have been adjusted but I have not tested the coil--which I don't know how to do and don't know if that would cause a problem anyway. I'm just frustrated because I've been able to get bikes with 4 carbs running well and this little one carb bike has me stumped. :frown2:
 

·
Registered
Joined
·
7 Posts
Discussion Starter #4
I’m now looking at the coil possibly being bad —or going bad— which could also be a source of idle problems. Ohm’ed the coil and only got a .4 ohm reading and the service manual calls for 1.4–1.8. Ordered a new coil and it gets only about .6. Used 3 different meters and got the same results. Still checking.
 

·
Registered
Joined
·
937 Posts
Subscribed. I have a Griz 80 and it's been very hard to start. The valves are in spec and the plug is black. I have some carb issues to resolve as well - I just haven't had time to tear into it.
 

·
Registered
Joined
·
18 Posts
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.
 

Attachments

·
Registered
Joined
·
937 Posts
Rpmstl - glad you got your little machine running so well. Mine needs some attention. Based on your valve info, I may need to readjust and try it again. I'm guessing the carb needs cleaned again too as it's been a couple of years and it spends a lot of time sitting. I'm not a carb pro so getting it set right will likely be a challenge. I appreciate your insight.
 
1 - 7 of 7 Posts
Top