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Discussion Starter #1
Hi all,

Brand new here and this, my first post, is due to mechanical failure and owner meltdown...

The bike died one rainy night in a flooded condition. No start so towed it home. Took carbs apart and cleaned everything and reset the floats. Bike started and idled great and more reponsive on the lower 1/4 throttle. BUT...

After many more attempts at cleaning the jets and floats and needles/seats, checking for vacuum leaks, fuel delivery ie; petcock, vacuum lock at the tank cap, lines etc. and after various float level settings, the engine still stalls out at just over 1/3 throttle.

Slides and diaphragm are clean and free sliding with good vacuum. Jets seem to be clean and floats are set. This thing has me baffled. New plugs as well.

Wondering now if I'm barking up the wrong tree and if I should be checking for coil output. Got plenty of spark at the plugs and the battery is fully charged.

As a note, nothing has been replaced except the plugs. Float needles and seat are the same as are the jets and o-rings. The bike was running and then shut off to a no start/flooded condition.

Any idea's appreciated!!
 

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Did you get fuel just before this started? Can there be crude in the tank?
Sure sounds like a fuel starve problem.
 

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Discussion Starter #3
Did you get fuel just before this started? Can there be crude in the tank?
Sure sounds like a fuel starve problem.
The tank was filled shortly before this happened however, I have checked the fuel in the tank and the lines and filter. I have bypassed the filter entirely and checked fuel delivery. Am still wondering about float needles and seats. They seem clear and work when I blow air through a hose into the float bowl. They open and close as intended.
 

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Discussion Starter #7
No real difference using the choke. You can hear the choke working but the engine stalls out just the same. I think either float needles and seat or accelerator pump o-ring or needle and main jet. I hate throwing money at it hoping I get it right.

The bike has had 7 owners previously so not sure what they all did to it. It has Cobra pipes and stock jets so should run/did run nicely for a month or two after purchase.
 

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Maybe there is a v-star 1100 owner on here that can give you the exact float height. I don't own the 1100 so I'm not sure how touchy the float is. While waiting for the info (if you don't already have it), you could always run a tank of sea-foam treated gas thru IF you can get it to run again.
 

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Discussion Starter #9
I have run combustion chamber cleaner through the carb while running to no avail. Have also adjusted floats to 11mm (factory), 14mm and 17 mm with no difference. That's what leads me to believe the float needle/seat or accelerator pumps are shot.

Was hoping someone had a similar problem to this to help pinpoint solution.

I hate giving up on these kinds of problems but hate even more going to a shop for help.
 

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Did you notice the colour of the exhaust? Was it coming out black just before it quit? This would indicate a rich condition or in your case a flooding condition. Comes back to what your thinking about; either float needle/seat or accel pump maybe even a broken float assy. Have you checked the plugs after the stall? Are they wet? If you open the carbs again; check the float assy's for fuel in them.
 

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Discussion Starter #11
Did you notice the colour of the exhaust? Was it coming out black just before it quit? This would indicate a rich condition or in your case a flooding condition. Comes back to what your thinking about; either float needle/seat or accel pump maybe even a broken float assy. Have you checked the plugs after the stall? Are they wet? If you open the carbs again; check the float assy's for fuel in them.
The exhaust has always smelled rich. I did check the float for signs of cracking but they are both fine. The floats work freely by blowing air through a hose into the fuel port. I can hear and feel the air start and stop as the float closes.

Gonna look more closely at the accel pump tomorrow.

Merci!
 

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Sounds familiar :confused: Once i had inadvertantly pinched part of the rubber diaphram while re-installing, had a very similar effect.

Another time the retainer cap had popped off and allowed the spring on top of the needle (looking down into the middle of the diaphram) to come off. This also had a similar effect.

Fuel for thought?
 

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Well you have tried all but 2 things that are in the trouble shooting guide so you might as well check them also. One is the timing and the other is the fuel pump. Also there is no accelerator pump to check in v star's.
 

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Discussion Starter #14
Sounds familiar :confused: Once i had inadvertantly pinched part of the rubber diaphram while re-installing, had a very similar effect.

Another time the retainer cap had popped off and allowed the spring on top of the needle (looking down into the middle of the diaphram) to come off. This also had a similar effect.

Fuel for thought?
I was wondering that but the problem surfaced before I took them apart with no change on a subsequent attempt after disassembly.

With respect to the accelerator pump, that's just what I call the vacuum chamber. The whole thing acts like a pump. Didn't mean to cause confusion...I have a habit of doing that! Point taken!
 

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Discussion Starter #15
Well you have tried all but 2 things that are in the trouble shooting guide so you might as well check them also. One is the timing and the other is the fuel pump. Also there is no accelerator pump to check in v star's.
I have checked the fuel pump and verified that it's not a delivery problem. I'm going through this thing without a manual so that might be my next step. I'm not sure how to check timing on this bike but will quickly learn...once I have the book.

I was thinking electrical but more along the lines of coil breakdown. The parts lady at the dealer said she doesn't sell many coils and says they rarely go bad. Will look into timing as a possible solution.

Whatever the problem turns out to be, I will post results here so a few less people need to go through this. It is fun and frustrating at the same time!

Thanks everyone for your input. Any other idea's...keep em coming!
 

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There is also a way to test the TPS, aka Throttle Position Sensor, which is on the starboard (that's the 'right' side :D) side carburator. You really do need a manual at this stage of the game.
 

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Discussion Starter #20
Just tested the TPS. Reading at idle is 5.06 ohms and at full throttle is 3.898 ohms. All within range.

The bike is white. Wondering if that's not the problem??
 
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