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Air/Fuel Mixture Screw Grizzly 660

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  #1  
Old 02-11-2008, 07:37 PM
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Default Air/Fuel Mixture Screw Grizzly 660

I have a 2007 Grizzly 660 with the stock Mikuni Carb. Can someone tell me where the air/fuel mixture screw is located? I'm an idiot. Thanks!
 
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Old 02-12-2008, 02:33 AM
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Default Air/Fuel Mixture Screw Grizzly 660

Its on the bottom, in front of the float bowl.
 
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Old 02-13-2008, 05:53 PM
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Default Air/Fuel Mixture Screw Grizzly 660

Would it be a bigger phillips screw located just in front of the float bowl? Thats the only screw that I see there. I see a hole where theres threads like where a screw would go which is close to where the phillips screw is I'm talking about but theres no screw there. Thanks!
 
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Old 02-14-2008, 04:58 AM
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Default Air/Fuel Mixture Screw Grizzly 660

There might be a plastic plug covering the opening. The mixture screw itself is a slotted head screw.

Its number 8 in th epic
 
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Old 02-14-2008, 10:30 AM
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Default Air/Fuel Mixture Screw Grizzly 660

More than likely it's not plastic... it's metal... You'll have to drill thru it to get to the air/mixture screw...
 
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Old 02-14-2008, 05:02 PM
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Default Air/Fuel Mixture Screw Grizzly 660

Yea I just looked at the Carb If I'm looking in the right spot its metal that needs drilled out. Thanks guys for your help and the picture. Much appreciated!!
 
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Old 02-15-2008, 05:12 PM
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Default Air/Fuel Mixture Screw Grizzly 660

Ok so i drilled thru and found the air/fuel screw. I adjusted 2 1/2 turns out. Now my problem is it seems like its idling fast. Before when I would first start it I had to have the choke on. Now it won't start unless the choke is off. If I put the choke on even a lil it shuts off. I can hear the belt winding up like the choke would be on. Also when I go to put it in gear it hits hard jus like if the choke was partially on. Any suggestions? Should I try adjusting the idle screw? Turning air/fuel screw back 1/2 turn maybe?

Next problem is when I go 3/4 to open throttle it is dying out. I have a HMF pipe and K & N Air Filter. I have the factory Mikuni Carb in with a 175 main jet. It is cold here now as it is winter. Temperatures haven't really been above freezing for a few weeks now with exception of a day or 2. Any suggestions there or just wait til it gets warmer? Would taking the K&N out and putting factory filter in help any?

Thanks again for any and all input!
 
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Old 02-27-2008, 02:02 AM
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Default Air/Fuel Mixture Screw Grizzly 660

Help Anyone???
 
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Old 02-27-2008, 03:04 AM
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Default Air/Fuel Mixture Screw Grizzly 660

What were your first symptoms, when you started the thread? How have they changed? What else has been done to it?
Usually a high idle is an air leak, check to make sure th eclamps and carb got mounted correctly, and there isnt a partially installed carb.
Did you remove the cover on top of the carb? Did it seal up correctly if it was removed?
 
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Old 02-27-2008, 01:09 PM
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Default Air/Fuel Mixture Screw Grizzly 660

Originally I added an HMF Pipe & K&N Filter. It was running rich as it was blowing alot of black smoke out tha pipe. I put the jet in that was sent with the pipe and I just recently did the Air/Fuel Mixture adjustment that HMF recommended. I went 2 1/2 turns out from lightly bottomed. Before I even did any mods I had to have the choke on when I first ran it or it would shut off immediately. When I first bought it new I didn't need the choke. Well after a few runs through mud and water thats when I needed the choke. Now after I did the air fuel adjustment the choke is working opposite. If I put the choke on even slightly it shuts down. The choke has to be completely off for it to run. Doesn't make sense to me. Also since doing the air fuel adjustment seems like my idle is turned up. When I go to stop it wants to keep going but not much. So doesn't seem like idle is up alot but is noticeable. My final problem is even though I added the jet from HMF it still boggs out at 3/4 to full throttle. Its winter here so it only has been above freezing a couple days in the past couple months. I was gonna buy a jet kit and play around with it but other people I talked to said wait til the weather warms and see if it has an effect on it. Any suggestions on what I should try? Thanks!!
 


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