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Discussion Starter #1 (Edited)
After more than 6 weeks of sitting I took the battery off the charger and fired up the bike. At first it didn't catch at all with chock. After several attempts I used 1/2 chock and it reluctantly started and idled about 500RPM. After several minutes it surged, I then was able to add throttle and even give it a bit more chock without killing it. This has happened before after the bike has sat. I'm wondering if the gas in the carb starts to vaporize and its partly dry??? I add a semi-random amount of Seafoam when I fill it. When I rode it a couple times a week a couple months ago it started fine.


I should add that I'm pretty confident in the carbs themselves. I mailed them off to Steve Reed last summer and he did a full overhaul on them. I also overhauled my fuel valve.

-Robert
 

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What kind of gas you have in the tank? Gas with ethanol absorbs water.

At six weeks your fuel in the bowls could have been contaminated. Sounded like you got only one cylinder going at first, then the other kicked in.

I'd try some fresh gas, a good dose of SeaFoam and go for a ride.
 

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If only it had 6th gear..
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Agree about one cylinder firing then the other lazily kicking in. Mine does that and a few others have mentioned it. Each bike has it's own personality when it comes to the choke. I use hardly any, but I also have aftermarket jets and typically these bikes don't need as much of a rich mixture when cold when running bigger jets in them.

Ethanol is garbage and most likely is the reason you're having problems after it sits. I've heard there are stations that have non-ethanol fuel but have no idea who does/doesn't. Might be worth it for you to search your area and try a tank full of non-messed with gas.

If ou have an OFF position on your fuel petcock, you could try turning it off and run it out of gas before you let it sit that long and see if that makes a difference but there are reasons why that isn't a good habit either.
 

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Not sure if the different year bikes have different petcock settings but my 86 has a prime setting. Put it on that before starting when the bike has sat for sometime and see if it helps.
 

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My '02 has only an on and reserve setting. A prime setting would be great for draining the tank. Six weeks is a long time to leave gas in the carbs. If I were going to let it sit that long, I would drain the carbs. Real easy to do, just slightly loosen 2 easy to get to Allen screws. Alcohol gas is indeed garbage, and the alcohol evaporates very quickly. I sometimes do let mine sit that long or longer, with the float bowls drained. I have a hand operated vacuum pump I connect to the vacuum line to the front carb, so I can fill the float bowls prior to starting. It seems to take a very long time to fill them when cranking with the starter, putting a lot of unnecessary wear and tear on the starter.

I have and always will be a believer in carburetors, but this alcohol gas IS making them less reliable, and makes them get plugged up easier.
 

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Discussion Starter #6
I also probably just need to do a better job of treating my gas. I know motorcycle types like Seafoam but its difficult to know how much you've added. I've used Stabil for years in my small motors and large motor boats with success. The boat sits for 7 months at a time with Stabil and alcohol fuel in it and fires right up the next season. I've had some small motors sit for a year or so and fire right up with Stabil. I really like the fact that it has a measuring tool on it. I suspect I'm greatly under using Seaform as a result in the bike.

-Robert

My '02 has only an on and reserve setting. A prime setting would be great for draining the tank. Six weeks is a long time to leave gas in the carbs. If I were going to let it sit that long, I would drain the carbs. Real easy to do, just slightly loosen 2 easy to get to Allen screws. Alcohol gas is indeed garbage, and the alcohol evaporates very quickly. I sometimes do let mine sit that long or longer, with the float bowls drained. I have a hand operated vacuum pump I connect to the vacuum line to the front carb, so I can fill the float bowls prior to starting. It seems to take a very long time to fill them when cranking with the starter, putting a lot of unnecessary wear and tear on the starter.

I have and always will be a believer in carburetors, but this alcohol gas IS making them less reliable, and makes them get plugged up easier.
 

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I also probably just need to do a better job of treating my gas. I know motorcycle types like Seafoam but its difficult to know how much you've added.

-Robert
They sell these things called "measuring cups"...metal or glass ones are a good choice for chemicals. A shot glass can even be used as a measuring tool...(that was it's original purpose.) :doh:

I used 2-3 "shots" of SeaFoam in a full tank as a periodic dose. For extended storage, I'd use a whole cup and run the bike to make sure it got into the carbs.

I've read one too many horror stories about using Stabil in bikes, so I only recommend SeaFoam.

:)
 

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I have used StaBil in bikes, but only the BLUE marine stuff. It seems to work fairly well, but the fact is, even with StaBil OR Seafoam, or anything else in gas, gas still evaporates. And when it does, it leaves sticky gooey stuff behind. It would take a long time for a significant amount of gas to evaporate out of a tank, but it does not take long for a float bowl full of it to evaporate, and leave residue behind. Thats why I recommend draining the carbs for storage. That way you drain everything out, including the part of gas that does not evaporate. To prevent corrosion in the empty carburetors, I recommend draining out all the gas, filling them with WD-40, then draining it out. It will leave a coating that will protect the metal, and yet is easily dissolved by gas when you fill them up again.

I have one Yamaha XT225 in extended storage right now, and have no idea how long it will be before I get it going. Nothing wrong with it, didn't even really need it, I have another one I use, but I got this one so cheap I couldn't resist. It ran fine when I bought it. The XT225 is my favorite street legal trail bike and it is getting hard to find nice ones. I have the carb apart in a tupperware bowl, the bike sitting up on a 5 gallon bucket with both wheels off the floor, there is no chain or front sprocket. The bike is in 5th gear, The tank was emptied and coated with WD-40, and the intake is plugged. About once a month, I remove the spark plug and the plastic from the intake, and spray 3 in 1 oil into the spark plug hole and the intake, then turn the engine over with a socket, then put the plug back finger tight, and the plastic back over the intake. This lubricates the valves and cylinder walls, and moves the piston in the cylinder to prevent the rings from sticking. I should be able to store it in a closed shed for years this way without damage.
 

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If only it had 6th gear..
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Good idea with the vacuum pump to fill the carbs. Even though a 2000 mine has the prime spot because I replaced the original valve. Don't really like not having an OFF position but haven't heard of a problem because of that. For measuring, I payed a whopping buck for a turkey baster at the super.. makes measuring the seafoam easy. Has the ounce lines on the sides of the tube :smiley_th
 

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I have used a 16 oz can of Seafoam in a full tank of gas in the Vulcan before without problems. I also use pure Seafoam to soak carbs in while they are on the bike. Just drain the gas out, close the drain screw, and fill them up through the fuel lines. You can also fill them up through the carb vent hoses, which on my bike are easier to get to.
 
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