1981 xs650 carbs not running right yamaha?
March 3rd, 2010 | Articles | 2 Comments »jim1075pierce asked:
hi i have 2 1981 xs650 yamahas bike 1 when i pull chock out it starts up ok. then i put chock in haft way then all the way in. after 1 min. it runs great. bike 2 when i pull chock out it wants to miss and run about 4000 rpm. i have to keep all the way out till it warms up then all is well can any one help me on this i think no. 2 bike may have a little dirt in carb. i dont know it runs great after about 5 mins.thanks for any help.
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hi i have 2 1981 xs650 yamahas bike 1 when i pull chock out it starts up ok. then i put chock in haft way then all the way in. after 1 min. it runs great. bike 2 when i pull chock out it wants to miss and run about 4000 rpm. i have to keep all the way out till it warms up then all is well can any one help me on this i think no. 2 bike may have a little dirt in carb. i dont know it runs great after about 5 mins.thanks for any help.
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bike 2 runs lean when it first is started. I would start by cleaning the carbs and looking at the jets on that bike. If cleaning did not solve the problem, then get one size larger pilot and mid range jets should. also take a look at the airbox for cracks, damage etc. Then make sure the filters are clean and the rubber manifolds are soft and pliable.
Usually if the engine runs bad when it’s cold, but runs good after it’s warmed up, then you have a lean fuel mix. You probably have some varnish or dirt in the pilot jets.