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Hello. I just rebuilt my carburator on my Artic Cat 580 and replaced the throttle cable and oil cable and am wondering if I have it set right. Wondering if my adjustments look right based off the color of the spark plugs? To sum it up....Do these spark plugs look like they are burning right? They only have around 10 hours use, Need some opinions. Thanks.
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You need to go to a step smaller main jet in the carbs. Jetting is something that needs to be changed for elevation and temperature. The denser the air is, the more fuel you have to have to remain in the safe air/fuel ratio. So if you go up in elevation, there will be less air, so you need smaller jets. Also, if the temps go up, the air is not as dense; again, smaller jets.

The reverse is also true; go down in elevation, put in bigger jets, ride in colder weather, put in bigger jets. Manufacturers make jetting charts to keep you in the zone (and to keep the engine safe!) Going too small in the main jet will cause a lean condition that can lead to excessive heat and holes in the piston(s).

Start by locating the appropriate jetting chart, which should be in the owner's manual or available online or through a dealer. What year is the ZR? I have a manual for a 94 carbed, I could scan the chart if it's around that year.
 

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Did you pull the plugs after a run, or did it idle first? Idle time on the plugs before reading them can cause them to read richer than it is at WOT. Shut the engine off immediately after a hard run and pull the plugs to get an accurate read.

Another way to verify mixture is by looking at the piston wash; look for about a thumbnail's worth of carbon to be washed off of the piston next to the transfer ports. More wash leans rich, less is lean.
 
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