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Hi mate reverse the needle clip position back to factory setting this issue is pilot circuit for sure - If you have cleaned carbi you need to replace or clean the pilot jet and compress air clean the hole where the pilot jet came out of to clear the circuit. Running only with choke on is classic symptom of block pilot circuit...
Also check you fuel air mix screw this may have been altered trying to correct this issue it should be 1.5 - 2.5 turns out from fully closed..
all the change of needle position clip is doing is allowing your bike to run off the main jet (not good)
and reason for running with choke on is it is changes air fuel mix with choke on compensating for lack of fuel from the pilot jet blockage
regards Jamie
The Yamaha manual says that each bike was individually tuned at the factory, and gives no spec. A good rule of thumb is between 1-3 turns out. If it wants to run at less than 1 turn out, change the pilot jet to the next size down and readjust. If it wants to run at more than 3 turns, go up one size on the pilot jet and readjust. Good luck!
three problems that i think off :
1 - plugged main jet
solution : remove main jets and clean with new fuel
2- pilot mixture too week
solution : adjust the pilot mixture to factory settings and recheck
3- water in float bowl
solution : drain float bowl
melting spark plug is too lean. exhaust gas high temps caused by too much air. your oil to fuel ratio is correct, but your air to fuel ratio is not. adjust your needle clip position to add more fuel to the carb by lowering the C clip. this will raise the needle, giving you more fuel for the same amount of air. also check air filter element for tears.
These bikes shipped with only one jet needle (unlike other Yamaha's) the bike's factory jetting is 45 pilot, NBKF needle on the 2nd clip from the top, and 138 main. This bike tends to run a little rich off the bottom, so I'd recommend running a 42 pilot instead. When it's really hot out (over 90) you can run the 135 main jet.
Screwwing with carbs is fact of life with these bikes - you will have to do some tweaking no matter what.
I would try cleaning out the carb or carbs clean out the float bowls. remove and clean the jets with solvent or carb cleaner works. Old fuel can clog up a carburetor
you don't! set pilot two turns out from fully in on carb pilot jet, start engine and set throttle adjuster screw on carb to fast tick over, adjust pilot to get even firing and readjust throttle screw to @1000rpm
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