Jetting and plug heat ranges

[W00TsP0P]

In my repair manual it says to change heat range of the spark plug when changeing the main jet + or - 3 steps but it doesnt say what to do with the jets when you change the plug heat range?
i have reverted back to yamalube 2R at 30:1 and started with the factory jetting. 410 main, 40 pilot, stock needle w/clip in #3 groove, BR9EG plug all the factory settings. i have done this to track down a oil fouling problem with my spark plugs. i have gone down on the main to 390.
do i leave the main at 390 and change the plug to BR8EG or do i put the main back to stock and change the plug to BR8EG

 

[pw50123]

Leave the 390 cahnge the plug to the 8. Test drive 4th gear check plug. Mine was rich down low so i change my pilot and dropped the needle one.

 

[Studboy]

My guess is that your fouling problems are stemming from the pilot/needle jet circuits and not from the main jet. Don't go to lean on the main, you will burn things down in a hurry.

 

[W00TsP0P]

i tried yesterday, no luck still we still fouled the plug
main 390 factory 410
pilot 37.5 factory 40
needle drop down 1 groove (raise clip)
BR8EG plug factory BR9EG

 

[Studboy]

I would try going even leaner on the pilot jet. If that doesn't cure the problem or if the bike runs lean (boggy), then I would suspect a right side crank seal.

 

[pw50123]

try a 35 or 32.5.

 

[W00TsP0P]

got the 35 pilot will try next week