How do you know if your sled is running rich? I noticed alot of oil and black crap on my plugs, I have a Yamaha XLV 540..im not sure of how to lean it out, or even if its an issue. any help would be appreciated!
To check if you are running rich or lean, run the sled WOT for 1/2 mile to a mile. Kill the engine stop as fast as you safely can. Pull the plugs out, also as quickly possible. They should be a tan color, some describe it as a cardboard color.
You dont really know where you are too rich?? You could be too rich at IDLE_________or 1/4-3/4 Throttle__________Or 3/4-WOT (Wide Open Throttle)
All which are different.
Idle- 1/4 throttle is controlled by Idle air screw, and Pilot Jets
1/4-3/4 controlled by needle, and needle jet
3/4-WOT: Main Jet
So you should test your jetting at all 3..........TO do this, just run your machine constant for at least 1/4-1/2 mile, then WITHOUT letting off the throttle hit the kill switch till you come to a stop and then pull the plugs and check the color, if you have a piston light check the wash of the piston as well...As stated white/grey NO GOOD< to lean, Dark Black > too rich.........Cardboard color/medium brown just right....
This is just coles notes on this topic, there are lots of articles on this subject if you do a search..
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