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Discussion Starter #1
I've got a 2000 V Star 650 Classic and have been having different starting issues. Essentially, I go to crank the bike and after a few revolutions of the engine, the motor gets stuck. I hit the starter and its as if it is stuck. Gasoline also comes out of the vent line. I am able to put the bike in first and push it to get the motor to move and then i can usually get it to crank. Occasionally, this takes two or three attempts to get the bike to start. Another less common issue is that during this starting process, it sounds as if someone slammed a hammer against the right side of the engine near the clutch. Its a very loud bang and definitely makes my wallet hurt instantly. Since yesterday, I have taken the clutch plates out as well as remove the starter clutch. I put the flywheel on my bench and turned the idler gear in the bearing and it seems to be functioning properly.

Anybody else experience these issues? I'm at a loss because after tearing this thing down, I still cannot find anything wrong with it.
 

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...Gasoline also comes out of the vent line.....
Stop what you are doing: ^THAT is the problem.

One of your float bowls is stuck open and it is flooding your engine with gasoline.

Since this bike has a fuel pump Im pretty sure the fuel pump is blocking the gas from flowing whenever you have the petcock on, but once you turn the key on , the fuel pump comes on,

and since the float bowl is stuck its flooding gas out the vent tube, and it sounds like its also pouring it into your intake valves!

This fills up the top of the piston with gas, and when it has filled up enough the piston cannot move up all the way - gas does not compress, and its slamming into your head

its called hydro-locking the piston. the same thing would happen if you took out your spark plugs and filled the pistons with oil, put the plugs back in, then tried to crank over the engine.

So:

1. You need to free up the float bowls so gas is no longer streaming out the over flow tube. You should be able to figure out which one is stuck by pulling the tubes off the carbs, and see which one is flooding out. You might be able to run some Seafoam mixed with gas into the carb, and then tap the carb bowl with a screw driver and get it to loosen up

BUT DONT CRANK THE ENGINE until you have fixed that. You can see if the float bowls are stuck just by turning the key on for a few second to run the fuel pump, and check the over flow tubes. You do not have to crank the engine for the fuel pump to push gas into the float bowls.

AND

2. your oil IS full of gasoline - you need to drain the oil, remove the oil filter, and do a complete oil change. A little bit of gasoline in the oil seriously compromises its properties. Dont crank or start the engine with all that gas in your oil.

I dont think you have destroyed the engine, unless you kept doing this over and over.

Do 1 & 2 and then the bike should start up and run.

Look around the top of the pistons and make sure the head gaskets have not been blown thru from the hydro-lock pressure on them.

You have a very good chance that is all you need to do.
 

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Thanks for the definition KCW. This is what the mechanic had told me had occurred to my bike from being left outside and unattended. A good cleaning of the carbs and draining of the oil should be good to go.
 

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I saw a guy ride a dirt bike into the ocean at a beach years ago. The engine sucked water right into the piston thru the air intake.

He pushed the bike out of the water and tried to start it. He was standing on the kick starter and it would not budge.

I told him to quickly take the spark plug out and kick the engine over a few times, to blow the salt water out of the combustion chamber (before it all soaked down past the rings). Put the spark plug back in and it started up.

People do this sometimes when they are doing a wet compression test - they put too much oil in the spark plug hole, and CLUNK! the engine wont turn over.
 

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Yep, hydraulic lock. My needle valve was missing the rubber nipple on the tip. If I let the bike sit for more than 30 minutes with the petcock open, the engine would lock on start. Forcing the engine to turnover during this situation puts quite the strain on the motor. If the floats aren't stuck- check your needle valves.
 

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Discussion Starter #7
I've taken the carbs off and checked and everything seems to be in good order. I Replaced the needle valves about 8 months ago so not sure if they would go bad in that amount of time.
 

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But that doesn't mean that they're shutting off fuel flow... IMO you need to remove the carbs, hook them up to a free flowing fuel line and verify that the valves are closing once the bowls have filled. Even if the needle valves and seats are in good shape your float height adjustment could be off to the point the valves don't completely close and allow the fuel to keep flowing.
 
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