have to choke her at full throttle

[rufusgooch]

have an old 91xp. full engine rebuild four years ago. yellow motor, dual carb. carbs reuilt too. ran great til end of last year. starts good, slight hesitation on throttle. will not run at full throttle unless u choke her. full throttle at 1/2 choke she runs at 30 all day. cut back on the choke and she dies. high spped screws ar set a 1/2 turn. any less and she wont run, any more and she wont run. is it time to rebuild the carbs again? or am i missing something.

 

[robin savell lloyd]

check compression in both cylinders if it is ok check for fuel restriction in fuel on off valve and fuel lines. if all is good I would thank carbs. you may be able to touch cylinder head with hand and find one side running hoter than other this could be due to lean carb this is all new to me so I may be wrong. good luck. robin

 

[seadoosnipe]

Pretty good......

Pretty good response Robin. I would add, check the in line fuel filter and as Robin states, if your heads aren't running hot and your compression is good, you may have trash in your carbs filter. The Mikuni SBN carbs have a little white filter basket in them. Really small, in the event trash gets by your primary filter, it won't get into your jets.........