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Discussion Starter #1 (Edited)
2007 V-Star 650 runs terribly and only on choke

My 2007 V-Star 650 has been sitting for a couple of months, maybe 3-4 at most. For personal reasons, I did not have time to ride it and I did also not have time to refuel it before it sat, so the tank was around 2/3 empty.

Last weekend I attempted to start the engine but the battery was dead. I was able to jump start it and ride to the post office and back, but the engine was running terribly. First, it would shut off immediately when idle. I was only able to keep it running at red lights by either revving the engine constantly or pulling the choke lever at least half-way out. Second, it was very hard to keep a constant speed as it would stutter and die, then come back to life and accelerate out of nowhere. While I was out I stopped at Home Depot and purchased a can of Seafoam, then put around 8 oz (half the can) it in the tank and fueled up. I've tried to leave the engine running but it hasn't improved a bit. It is still very hard and rough to start, it still shuts off immediately when idle without the choke lever pulled out even when it's warm (I took it around the block and it even died on me twice out of nowhere), and I have the feeling that the engine sounds pretty rough and almost violent.

Any ideas what else I could do? Any carb / fuel system cleaners that are better than Seafoam and that will blow all the gum, gunk and build-up out of the carbs, jets, etc? If possible I'd rather not take it apart because I won't have time for that in the coming few months (baby girl due in January) but I'd still like to ride it every now and then when I have the possibility.
 

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I'm not the resident forum expert on Seafoam but I believe I read that it won't completely clean the carbs if it's just idling. You need to drive it at various speeds and RPMs with the Seafoam in it for it to work.
 

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If the bike had 10% ethanol fuel in the tank when you parked it, the fuel has broken down / degraded.

If you had put 4 ounces of seafoam in the tank when you last filled it with fresh gas, and then parked it for 4 months, it would have stabilized the fuel and it would run ok.

But Seafoam can not restore the gas after it has already broken down. Get a pair of plyers and a bucket, pull the fuel line off the tank (one end or the other) switch the tank shutoff to reserve and drain all that bad gas out of the tank. The reserve position will drain the tank completely).

Put the fuel line back on the tank, then pull the line off that goes to the carbs, point that at your bucket and turn the ignition key and kill switch on and let the fuel pump run for a few seconds and blow all that bad gas out too. Dont crank it, just let the fuel pump run till it sucks air. Put the fuel line back on the carbs.

Then put fresh gas in the bike with 1 ounce of Seafoam for each gallon of fuel. You dont have to fill it up all the way. While you are at it look in the tank and make sure the 2/3rds of the tank that had no gas on its surface did not rust up on you.

With fresh gas and the right ratio of Seafoam start the bike up again and take it for a ride. There are 3 stages of "jets" in the carbs, at idle you are using one, just above that the PM screw ports, and when you get to about 1/2 throttle you are well into the main jets. You will need to ride the bike for about 40 to 50 miles, with gas going thru all three passages as much as possible (ie: when you get on a bit of a hill open the throttle up wide, then slow down, speed up again.. but dont get carried away.

As long as the engine is running and fuel is flowing thru the jets and ports, the Seafoam has a good chance of clearing out the goop and jello from the bad gas.

There is about 2 table spoons of gas in the float bowls, that will take the bike about 1 mile down the road. Its possible once you get the fresh gas into the float bowls it could run much better. Its a lot of work to try to drain that bit out of the float bowls, easier to just burn off that little bit by riding it.

Let us know what happens.

BTW, if you dont know what to do with the old gas, dont do anything stupid like trying to burn it, and dont put it in your car. Just leave the bucket outside some place where it wont fill up with rain, and no critters will get into it, and it will evaporate away completely in about a day or two.
 

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Forgot to mention: If you ride about 50 miles with the fresh gas/seafoam, and the bike is not improving, then you will have to think about cleaning the carbs. If a jet or passage is completely plugged with goo, the seafoam cant flow thru it and clean it out.
 

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Unfortunately at least 90% of posters that have experienced simular situations never get their bike to run correctly with a carb rebuild. If you are the least bit mechanically inclined you can rebuild them in a few hour. Follow KCW suggestions first and hopefully it works. Keep us informed.
 

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Discussion Starter #6 (Edited)
I know it's been a while but I wanted to give an update on the situation. First of all, let me thank y'all for your awesome suggestions and help, especially KCW. You guys rock :smile: The bike is running again as if nothing ever happened, and I didn't have to take it apart.

I should add that I'm not a complete beginner when it comes to working on bikes. I've been working on motorcycles and maintaining my own fleet for around 15 years now, and have had everything from a late 80s XJ600 with 4 incredibly hard to synchronize carbs to an XT600 and DR350 with as simple a carb as you can get to a brand-spanking new fuel-injected BMW R1200GS or XT600Z in my garage (the latter was surprisingly easy to work on by the way). However, in all my years I have never had to deal with a clogged or clotted carburetor even if I let the bike sit for 4 months at a time. And since I spent a huge part of my life in Northern Europe that happened pretty much every single year. The only thing I always made sure of was that the tank was full before I stored it for the long European winter.

Here's what I ultimately fixed my V-Star: first, I let the carbs run empty and took of the fuel tank and disconnected all the fuel lines to drain it completely. Running the pump with the lines disconnected helped as well, thanks KCW. Wouldn't have thought of that. I should also add that contrary to popular belief the fuel hadn't gone bad yet after sitting for a few months, as a friend's lawn mower bore witness to, so I put it in my car, added the rest of the Seafoam and filled the tank with fresh gas. The car ran perfectly fine with it.

Then, on a nice and warm day in January, I purchased Berryman B12 carb cleaner, added a bit to my fuel tank, filled it with fresh gas, and went for a ride in the somewhat hilly neighborhood. The engine was running as rough as before on the first few miles, but with each passing mile it got better and better, especially after following KCW's tip about going full throttle on uphill sections. The neighbors must've surely been annoyed by the lunatic going up and down that one hill over and over again :grin: But it worked like a charm, and 30 miles later the system had improved to the point where the engine wasn't dying in idle anymore and ran almost perfect on low load and half throttle up to around 40 mph if I accelerated slowly. Full throttle and speeds above 40 mph still caused it to cut out, sputter, and eventually die after a few seconds. Unfortunately, I ran out of time (or rather out of Texas January sun...) and had to call it quits for the day, so I let the carbs run empty again and put it back in the garage.

Earlier this week I had an hour to spare again, plus the Texas state inspection was due, so I decided to take it out again. And to my shock and surprise it ran perfectly fine even on full throttle as if nothing had ever happened. Smooth, quiet, with no misfires whatsoever. The B12 must have worked its magic around fuel jets. After around 20-25 minutes I took it out of town and it eventually started sputtering again when doing around 60-65 mph or trying to accelerate full throttle, but it never died on me again. Three days later I took it to get inspected fully expecting it to cut out again at 55-60 mph but lo and behold: it runs perfectly fine now, accelerates without sputtering to 75 mph (couldn't go any faster around here) and does not cut out, sputter, or die randomly anymore. I've now done 70 miles since that first early January trip around the neighborhood and had no issues at all anymore.

Seems like I'm one of the lucky 10% that got away without disassembling the carburetor. I was ready to do so if the B12 hadn't done its job but it seems like I got away this time :smile:

Thanks again for your input and help, it was greatly appreciated. First time working on a new-to-me bike is always rough but I know I'll eventually get used to the V-Star and will be able to help others as well one day.
 

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thats great news, your experience is valuable to others with the same old-gas issues.

I was laughing out loud about you riding up and down the same hill WFO - it does work - picture the gas and cleaner rushing thru the jets and clearing out the gunk.

I started driving in 1975 and left VW beetles sitting for over a year, jumped in turned the key and they came to life like the bug in the Sleeper move that Woody Allen found in the cave.

The difference is 100% due to the 10% ethanol in the gas, it breaks down within months, and after a year you have a real mess.

I had the same experience when I got my Royal star, V4 with 4 carbs. The previous owner had gotten down to where he was only riding it once a year to get it inspected. He said he drained the old gas out every winter, but when I bought it the gas looked like coffee. I drained it all out within 10 miles of buying it and driving it to work, did the Seafoam cleaning. It ran rough for over 100 miles, esp in 5th gear at 70 mph - then all of a sudden it came to life. I think one of the carbs had the main jet mostly plugged, and when it opened up it ran like it should. That and the fact that all 4 spark plugs were only finger tight.

For those of us in the northern states riding is like owning a boat, you never know in the fall when your last boat or MC ride will be, so its best to play it safe and start treating the gas when you fill the tank late in the fall. You only need 1 ounce per gallon, so the $8 sixteen ounce bottle is good for 4 tanks of gas (about 1000 miles on a 650). That $8 is cheap protection when the weather goes sour sooner than expected.

The other thing to remember is you have to put Seafoam in the tank when you fill it with fresh gas. After the bike has sat for a few months, nothing can restore the old gas, you have to drain it out.
 

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Discussion Starter #8 (Edited)
It ran rough for over 100 miles, esp in 5th gear at 70 mph - then all of a sudden it came to life. I think one of the carbs had the main jet mostly plugged, and when it opened up it ran like it should.
I think this is precisely what happened with mine. One of the jets must have been completely clogged, and the B12 worked its magic after I drive a couple of miles just sitting there in the garage.

Regarding the E10 fuel: I can't really comment on that as I don't have any first-hand experience just yet. Strictly speaking even this issue wasn't related to the fuel degrading but the carburetor gumming up with gunk. The fuel itself turned out to be perfectly fine. Not sure about the US, but Europe has been running on E5 (5% ethanol) for decades and only recently introduced E10. With E5, I sometimes had it sitting in the tank for 8-9 months in my secondary motorcycle without any fuel stabilizers whatsoever and it started up and ran perfectly fine every single time immediately. It was a DR350 with kickstart only so bad fuel would've been very obnoxious :smile: To be honest I was completely unfamiliar with the concept and existence of fuel stabilizers until I moved to the US recently. Even now with E10 widely available it's an absolute non-issue in Europe - I wonder why that is and how European E10 fuel differs from American E10 fuel.
 

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its possible in Europe they put some level of fuel stabilizer in the ethanol blended fuels.

Seafoam is 50% naphtha (lighter fluid).
 
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