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Discussion Starter #1
First off - I see a lot of carb questions already this week!

I've got a 2001 V Star 650 Classic that I've for 2 years now. Since about late October, I've had an issue that I'm ready to try to diagnose and fix...

I mainly use this this bike as my commuter bike, which is about 10 miles each way. Cold start is fine (with choke). I can reduce choke to the lowest 'fast idle' setting after about 30 seconds at 25° F and go completely off-choke in about 2 blocks. After that, things seem really normal until I'm about 3 miles from my destination (either way - to work or home). For that last 3 miles, the idle speed is unusually high and, I can't rely as much on engine compression for deceleration. Another symptom is, the exhaust smells of unburned fuel when I get to home/work. Two weekends ago I replaced the air filter - thinking a dirty filter was 'choking' me. It was dirty (gray but not fully trashed) but, replacing it didn't make that much of a difference, if any. Also, while I had the filter off, I had a strong smell of gasoline from the airbox. (I'm not used to smelling gas that strong when taking the air filter off a carb.)

Maybe unrelated but, a few weeks ago, I took this bike on a quick grocery run (from stone cold about 1 mile to the store). As I was in the parking lot on my way out, this guy was giving me what I thought was a 'stink-eye'. I slowed down and he held up his index finger at me. (???) I stopped in front of him and lifted my visor and he says: "your only running on one cylinder". Now, this is my first V-Twin but, back in the day, I could tell when a V-8 was missing on one cylinder. I'd like to think I could tell if a two cylinder was only hitting on one but, maybe not? Anyway, I 'blipped' the throttle and he said, "OK, then it was on both". (?????)

I've run two whole tanks with Seafoam through it (recommended 1 oz/gallon, or maybe a bit more - I was eyeballing 3 oz). It hasn't made any change. I'm planning on replacing the plugs real soon (this weekend?). I was wondering if anyone had any thoughts on my symptoms. I'm not afraid to do a carb rebuild. Back in the day, I rebuilt Rochester QuadraJets so, I think I should be able to work through these. (Any input on carb kits welcome!).

Mind you, I have no real maintenance history of the bike. 2001 model, bought in March 2017 with 10,500 miles... now at 18,000 miles. Any thoughts appreciated!
 

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a vacuum leak is the obvious starting point for a high idle, assuming you are sure your throttle is not hanging up and sticking open
but a vacuum leak would make the bike run lean, not rich

the choke slipping back out, but thats not likely

pull the plugs and see if they are carbon'ed up, verify its running rich, because thats a whole other set of things to go after.

BTW, its easy to see if the bike is running on one cylinder, take your glove off and slap your exhaust pipes quickly with a couple fingers you dont really need... A dead cylinder will get warm from the compression, but it wont get hot like the other one.

Every spring when I take my 650 for the first ride after 3 or 4 months, it sometimes seems like its only running on one cylinder, and it seems really LOUD... but its just me - after not riding for a few months I forget what its suppose to feel like, but it comes back quickly.
 

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Discussion Starter #3
KCW - Doesn't seem like a vacuum leak. That wouldn't explain the fuel smell I get in the exhaust and the airbox with the filter out. Choke - I agree; unlikely. I have futzed with the throttle cable to make sure there's nothing going on there, even when its hot and idling fast. I'm going to try to get new plugs before the weekend comes. It should be warm enough to change them out and get a look - see if that tells me anything.

This bike doesn't sit around in the winter. If no snow/ice/fresh salt - I ride it to work. I think from all of December through March, I drove the car maybe 20 days. I think my longest stretch of not riding her was a full week.

Still not really sure I believe the guy about running on one cylinder. But he seemed really sure of himself about it.

The only other thing that comes to mind is, I first noticed this shortly after I had a local shop install my heated grips. I can't imagine he was close enough to the carbs to do anything to them so, I just chalked it up to coincidence but, I'll at least pull the tank and see if maybe he pulled something loose while routing power lines. Lord knows the 'favor' he did me of putting longer bolts on the battery terminals to accommodate the additional wiring was no great favor. They were too long to cinch down - they had bottomed out. Fortunately, he set the old ones down on the soft saddle bags and they rode all the way home there!
 

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The shop installing the heated grips is the start of the issues....

He might have unplugged the throttle position sensor, which would throw the ignition advance off, depending on what it reads with a disconnected plug

Some of these bikes have carb heaters - if that connector is loose now we are in the right ballpark, temp related, bike warms up, carbs get colder and colder from the incoming air... Not sure if 650 has carb heater

certainly worth a look under the tank, also check the vacuum gauge connection T caps (below the carbs, left side of biek) and make sure they are there, that is the obvious place to get an easy vacuum leak.
 

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Discussion Starter #5
I'm pretty sure there are carb heaters. Would a 2001 bike even have electronic ignition? I know that started on cars in the 80's. Maybe I was wrong to dismiss the problem as correlated to the grips. Picking up plugs tonight. Will definitely be poking around under the tank this weekend!
 

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All the Vstar bikes have electronic ignition - no points or condensers

about half have fuel injection instead of carbs

there was a change in the early 2000's.. something about the connections between the carbs and the Engine Control Module... and it might be something about the position sensors

either way, if you find a loose connector, or a connector with a wire pulled out, you found it.

While you are in there make sure he did not add a wire and jam it in under the tank where it can snag the throttle or choke movements - its pretty snug under the tank - also make sure your air intake box is still seated to the top of the carbs - he might have bumped that and knocked it loose - there are two hose clamps that hold it to the top of the carbs, and it can be a PITA to put back on. The bike wont run right if the air box and air filter are not connected.
 

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Discussion Starter #7
Anything that would keep me from a carb rebuild! Not that I don't think I could do one ... well, two but ... Hoping that's not what I need!
 
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