ok guys i have tried to set it ,,but mixture settings is not 100% ok,, i first fully closed the air/feul screw in then screwed out one and a half rotation,, that is fist ,, that is rotated three times out from fully closed at 180 degrees rotation each,, ,, if any one knows exact settings plz do mention,,
now i have another important question,, as u know that the fuel air mixture settings are set by carb and at different altitude the settings are not same,, i adjusted my carb [from mechanic] and went to murree ,, now islamabad is at 500 meters sea level and murree is at 2000 meter sea level,on the way to murree i checked the spark plug at different places and every time i found the mixture to be very very rich ,, that is the carb was extremely black and oily, i tried to play with the screws but i couldnt adjust the mixture to correct proportions and bike had lost all power even in first gearon relatively short flat slope it was stalling even in first gear,, whareas at the sea level of 600 at margalahills it went rocket even at extreme slopes,,
so after coming home i found that the main jet has to be chnged according to altitude.. to achieve a perfect ratio... so my questions are
1: to to identify which number of jet to replace for optimal performance..
2: since to replace to the main jet on current carbs one needs to open the entire carburetor and its very lengthy process .. whareas i have heard that snowmobile have a type of carburetor where the main jet is accessible externally so u can just change it externally without having to open the carb .. just like taking out idle speed screw or air feul mixture screw out... and replacing it.. so are such carbs available in pakistan particularly in islamabad rawalpindi and where at what price.? as an example of such carb here is one
20MM Carb Basics
3: more info can be obtained by searching rejeting carb for sea level.. i have honda ct70 manual there they have shown some plots on how to choose the number of jet .. and those plots are available online as well here i am pasting a link to an excellant site
Motorcycle Carburetor Theory 101