650sx runs like pooop

just got this 650sx in great shape but it has ben sitting for some time. put clean gas in it and she started rite up. when i put it in the water it just wont rev up and smokes like a pig:261:
 

Waternut

Customizing addict
Location
Macon, GA
Could be as simple as too much gas, too little gas, or the spark plug wires are corroded and need to be trimmed back an inch or so. Typically your ski can idle on one cylinder but if one plug isn't firing and you're only running on one cylinder, you'll never get planed off and you'd be dumping unburned fuel into the exhaust which might explain the smoke.

Since you say you just bought it, it could be something much worse too like the rings are shot and the compression is low in one or both cylinders.
 
It's been sitting for some time too? I would do a compression check first, if it's 125 or higher then it's good. My last ski was 123 even and ran perfect, it was a 92 650SX. If the compression checks out then I wouldn't hesitate to have the carb cleaned and drop a kit in. You would need to have the carb soaked though for about a half an hour or so to clean out the old stale gas that may be in the progression ports which would make it run like a dog. If you go to an auto parts supply store like Napa or maybe Pep Boys, you can buy a gallon or two gallon pail of Gunk brand Hydroseal parts cleaner, or you can take it to a bike shop and have them soak it for you. Brake clean won't do it if there's port blockage going on.
 
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Shonuff

I've got the glow
Site Supporter
Location
Memphis
I would tear the carb down, clean the filter, and hose everything off with carb cleaner.
In a confined space.
Breathing deeply.
Pondering life.
 
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