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Discussion Starter #1
I bought my first vstar 3 weeks ago. An 05 650 classic. Last bike owned 1980. I'm rusty on mechanics so really need help with this problem. RPM is slow to return to idle after throttle up in neutral, bike on stand, or clutch lever engaged in any gear when bike under load.
 

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Discussion Starter #3
re: lube throttle cable

Sugar Bear, I had sight checked throttle cables at carbs last week and they seemed to function(push-pull) normally in response to throttle position. I will lube cables and connections tomorrow as per your suggestion. Haven't lubed yet, just looked at cables. Thanks for your help. Will post result as soon as I can.
 

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Throttle cable free play

Something that might come into play might be throttle cable free play. I have not encountered this but the manual says if not correct Idle speed can change as you turn handlebars side to side. There should be 6 mm of free play in the throttle grip without moving the cables.

It would seem though as sugar bear said since they are carburetors that linkage or cables would be high on the priority. See if any linkage seems sluggish. Maybe lube the linkage and cables and put some cleaner in the gas. I like Sea Foam. Don't know if carburetor sync could affect this or not. Carburetor sync seems to affect several things. If all else fails you might look into it.

Dave
 

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also sticking needle valves could cause throttle response issues more likely on the decel. i had that issue on my Kawasaki ZX6R tore down carbs found all gummed up needles cleaned up and issue solved
 

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Discussion Starter #6
Thanks for your advice guys. Will clean, lube, adjusted cables this morning, and will add heavy dose of sea foam to tank if lube/adjust doesn't work.
 

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Here is another thought, as this happened to me. This fall before storing my 650 for the season, I had the valves adjusted and the carbs cleaned. When I got it back, the bike started and idled normally, and I took it on a run. After it warmed up, the bike would not idle down during shifts, and when I stopped, the idle was just a bit higher than it was before service. I simply turned the idle down, maybe 1/2 turn, and it was back to normal.
 

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Discussion Starter #8
update on fixes tried

throttle free play o.k., about 6mm. Turned bars full left & right, rpm stays constant. Lubed cable ends. Added 6 oz. of sea foam to 4 gal. tank, and rode over 100 miles today. Still had slow rpm decrease. Stopped at a cycle shop on way home, haddened been to before. A one owner/mech shop. We talked awhile and went out front. He started my bike and throttled up and down to idle a few times. He thought my idle was to high so he adjusted it down. Still didn't fix problem though. He said he could pull carbs, and check out everything in about an hour and a half, fifty dollars an hour labor. Not giving up yet though. Plan to put some more sea foam in and run it through, to see what happens. Thanks alot guys for all your suggestions in trying to help me out. Will let you know when it's fixed, and what was causing the problem.
 

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Cheap

Berserker, give the Sea Foam time to work. The $50 and hour sounds good for todays rates. An hour and a half doesn't sound too bad either. The fact that the guy took time to adjust the idle sounds good. Guess you just need to know if he is a reliable dealer. Let us know what the outcome is. Might help the next person.

You must be somewhere it is warm.

Dave
 

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With my stuff I have found this to be true, sometimes it has taken a few tanks loaded with Sea Foam , Lucas or a like product to do its thing, but it has worked out if that was the trouble. And yes, 50 bucks an hour sounds very fair with what I have to pay these guys. As was said about cable adjustment, I also had that , if I turned the bars lock to lock, reved big time, tiny little things can make big headaches at times. Really hope you get er and let us know. Thanks.
 

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If the bike sat for any period of time the pilot jets in the carbs may be clogging causing a lean mixture.Sounds like you've checked everything else.I'd have 'em pulled,dipped,and rebuilt.Those are funky in the way that they are put together and mounted(sideways).The bowls and jets can be accessed from the left side(sitting on it) of the bike without pulling the tank or carbs.I would let someone experienced(and trustworthy) do the work.I've gotten several bikes as of late that have been to other so called "reputable shops" for carb work, that after disassembled were shown to be done half ass'd. Be careful out there!!!! Ken
 

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Discussion Starter #12
Rpm Problem Fixed

Hi guys, sorry I took so long with this fix. This past friday I took bike to that one mech shop that I found a while back, and asked him to pull the carbs. Picked the bike up today. He said he took carbs completely apart and checked and cleaned everything. Charged me for two cans of carb cleaner in the process. He found one clogged jet and some other crud. He also synch'ed the carbs. I took bike out for a spin and rpm was quick to drop when throttle off, through up and down shifting. Also when reving engine in neutral. I believe he said needle jet. Hopefully this will help someone else with simular problem.
 

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Thanks for the update. It is always nice to find out what the fix was. I think it helps us all learn a little more about the way our bikes operate.
Ride safe
Doug




Work to Live and Live to Ride, after all it is about the journey.
 

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05 VSTAR 650

I've been searching for some tech info all over.

Last year I noticed the RPM would not rise and fall normally. The RPM would increase with throttle then slowly drop back to idle over 5-10 seconds. I began a regimen of SeaFoam and eventually stored the bike for an extended period with nothing but SF in the tank and carbs.

Now the thing won't run. Drained the carbs and tank. Refill with fresh tasty gasoline. Bike fires up like a champ then dies. Once in a while I can get a few seconds of rough idle.

I opened the float bowls and observed a green, moss-like, substance 'growing' on the brass jets. Cleaned the jets and reassembled.

Now it's slightly better but still won't even idle at full choke.

I took the entire carb assembly out and found that one needle jet was 'stuck' in it's sleeve.

HERE ARE THE QUESTIONS:

Is this consistent with my symptoms (no idle)?
Is SeaFoam really supposed to be this way?
 

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Discussion Starter #15
Roller.tron

sea foam will not grow anything in your fuel system. sea foam will not burn either . it just passes through your fuel system loosening crud from surfaces. sta-bil burns, sea foam doesn't. can you run it long enough to sync. carbs? rpm slow to return to idle may be unsynced carbs. good luck in finding your fix.
 

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Nope. Won't run more than 1-5 seconds at a slow idle. I've tried upping the idle but anything that would make a difference means it just doesn't run.

I took the carbs off and found that the rear needle jet was stuck in the 'nozzle.' I freed it and will be attaching everything back soon. I also bought 2 new pilot jets since I was told I should be able to see light coming through them.

The main jets were crudded also but a soak in cleaner and a piece of wire cleaned them out.

The float bowl has a brass tube that's not labeled in the schematic. From left to right I have:

Pilot jet, Main Jet, unknown - Am I right thinking this is the fuel inlet from the needle valve?
 

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Fuel line

Do you think the fuel line or filter could be blocked? The bike runs untill the float bowl is empty then stalls?

Dave
 

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Discussion Starter #18
Rollor.tron

Yes, your right. That is the needle valve. Hopefully with your reconditioning of the carbs and new jets you'll be up an running. Be sure to check your fuel filter too. Sometimes the simplest things are the problem.
 
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