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Discussion Starter #1
hi, i bought my 1st carburetor bike so am not exactly sure what to look for when it comes to carb problems.
If anyone can briefly read my post and point me to the problem.

Symptoms are simple:
Smell of gasoline even when i ride.
Smell of gasoline when bike is parked in the garage.
NO LEAKS
Rear cylinder too rich.
Quickly opening throttle over 50% causes black smoke coming from exhaust of rear cylinder when NOT riding.
When riding, cant get passed 65mph. If i try to go faster, bike starts to almost like choke or flood.

What i have:
2001 V star 650 with only 7k miles
Cobra pipes (not sure if slip-ons or not)
AIS remove (i was only able to get to 60mph so removing it was a benefit)

What i already did: (so you wont have to tell me to go do it again)
Clean carb:
Swap every interchangeable part from left carb to right carb with absolutely no effect.
Both ignition coils are at 20k ohms (good)
Needles are at same adjustment mark
Brand new pilot and main jets.
Opening choke during high speed hesitation makes it even worse.
Swapping spark plugs made no difference.
Valve adjustment did not help.
I dont think i have a timing issue. (no timing light to check)


If anybody wants to see my automatic cooling fan mod, go here



Thanks !
I hope you guys can help me solve this problem.
 

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Given the age of your bike and the low mileage, I presume its spent a lot of time sitting. My first suspicion based on the gas smell and richness is a bad float and/or clogged up & not-seating properly needle valve feeding too much fuel into the one cylinder. When you did your 'carb swap' were the needles and floats included? Did the richness stay on the same cylinder afteraward?

Most of the symptoms you describe could be caused by that. Sitting idle (especially with ethanol-laced gas) would tend do that, especially a 'glazed up' needle or seat. Is your oil getting 'gassy'?

You could try running a tank laced with SeaFoam through it. But I suspect what you really need is a complete (at least lower-end) carb rebuild.
 

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Discussion Starter #3
Age+Mileage does not mean my carbs are bad, i cleaned them right after i bought the bike few weeks ago.

This bike has 2 carbs so i was able to swap parts from one to another to see if anything would change.
Nothing changed, indicating that both carbs are clean and work equally well.
Everything is clean.

I think one cylinder is pulling more vacuum but i cant test that until i get the vac tester kit.
Seafoam did not help even a bit because carbs were clean and checked multiple times.
 
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