FMF with the lid off needs more than a #260 main jet.
#290,#300 is a good place to start, needle on middle clip.
Plug chop to confirm.
#290,#300 is a good place to start, needle on middle clip.
Plug chop to confirm.
Do i need to rejet?
- Thread starter blasteraz
- Start date
so i took the carb apart and it already had a 270 in it. the lid has been on and pulled the plug and was black with a lil oil. if i keep the lid on with a k&N and full fmf the 270 should be fine then? i didnt look at needle position since on fmfs website they said 3rd position and that should be stock according to blaaster.
For peace of mind to make sure everything is good do a plug chop.
Plug chop.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, roll to a stop.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
This is a good to go plug.
This one is a little rich, but I would run it, I like to be on the safe side.
Plug chop.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, roll to a stop.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
This is a good to go plug.
This one is a little rich, but I would run it, I like to be on the safe side.
