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Discussion Starter #1
Today my wife and I and some friends took a little trip down to Daytona. We went I-95 on the way down (SUCKS with no windshield!!!) and then came back US1. We were basically running between 65-75 the whole trip. We filled up before we left and as we were coming back I noticed I was getting really low on fuel and was thinking I need to stop at the next station. But I only had gone 115 miles on the tank so I figured I had a little more since I usually go around 130 before filling up and have never had to go to reserve.

WRONG! She started coughing and sputtering so I pulled over to a side road. I figured I would just switch to reserve and go to the next station that was less than a mile away. Wrong again. I switched to reserve and no crank. Tried and tried but no luck. I switched to off thinking something was just wrong with the petcock, no luck. So my buddy went on up to the gas station and bought a small can and some gas and brought it back to me. I dumped it in the tank, put the petcock on run and was good to go.

Now, I have two issues. I can't crank the bike up at all without giving it some throttle. And after a bit the idle drops and it stalls. My thought is that I probably got some crap from the tank in the carbs and it's clogging something, right?

The other issue is with the petcock. Why did reserve not work? When I got home I moved it to reserve and it cranked up fine, with me giving it some throttle. But any thoughts on why it will work off of reserve but not when it seems like it should? Could there be something wrong in the petcock so that reserve is acting like normal run and vice versa?

I really don't want to pull the carbs off but I have been contemplating doing an ear shave. If I have to pull the carbs to clean them I might as well re-jet them and pull off all the emissions crap while I'm in there I guess.
 

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Prowling Tiger
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Couple things come to mind: 1.) POOGS and 2.) Hot start problem. A rider should be able to switch to reserve w/o needing to stop the bike unless circumstances demand it. I can't recall ever stopping to switch to reserve before continuing on. I hope others will chime in soon.
 

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romeobravo172
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I too like Blaz thought maybe POOGS, but doubt that to the fact you went appx 115 miles (you mentioned about 130 usually before switching). From what I'v read poogs usually happens at around 1/2 tank. I had on a couple ocassions almost the same thing happen to my me on my 04. I always set my trip odo to 0 when I fuel up as I learned that at about 120 miles I am going to get that little surprise of a cough,sputter or whatever that says switch to res NOW! I found that after the motor did shut down that it would not fire right back up, after switching to res. I would crank it over for about say 5 secs then wait about a minute and crank it again for about 5 secs and wait again and usually about the 3rd or 4th try it would fire off. Think it takes a few minutes to replace the dry bowls and fuel lines that are dry and get the air out also.

You might try flushing the drain bowls (easy to do and get to) if you think you may have picked up some small trash in there. Wolfie swears he blows his out backwards often and that works as well. And there is always seafoam!

I do not think you have a PC problem. If the bike runs in the res position it should be getting fuel thru the lower inlet tube which is what the res is.
 

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Prowling Tiger
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I too like Blaz thought maybe POOGS, but doubt that to the fact you went appx 115 miles (you mentioned about 130 usually before switching). From what I'v read poogs usually happens at around 1/2 tank. I had on a couple ocassions almost the same thing happen to my me on my 04. I always set my trip odo to 0 when I fuel up as I learned that at about 120 miles I am going to get that little surprise of a cough,sputter or whatever that says switch to res NOW! I found that after the motor did shut down that it would not fire right back up, after switching to res. I would crank it over for about say 5 secs then wait about a minute and crank it again for about 5 secs and wait again and usually about the 3rd or 4th try it would fire off. Think it takes a few minutes to replace the dry bowls and fuel lines that are dry and get the air out also.

You might try flushing the drain bowls (easy to do and get to) if you think you may have picked up some small trash in there. Wolfie swears he blows his out backwards often and that works as well. And there is always seafoam!

I do not think you have a PC problem. If the bike runs in the res position it should be getting fuel thru the lower inlet tube which is what the res is.
Basically, when the tank runs dry and you let the motor die before switching to reserve, all the lines and the carbs are dry. So, the rider ends up having to prime the carbs off the reserve side to get the bike started again. I suggest practice locating the petcock while you ride to help avoid this scenario. If the rider can switch to reserve before the motor dies, it should pick back up and keep running.
 

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FREEBIRDS MC CENTRAL NY
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if you do have to get into the carbs i would shave the ears.most vulcan's love them
 

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Just a regular guy
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I agree.... I have gone dry twice... both times it took a bit to get it to start after switching to reserve. Plus... maybe there is a rust particle in the reserve portion on the petcock.... my original petcock had not filter for the reserve...

As far as the idle dropping and it dying.... try the blow back and Seafoam trick.
 

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Linkmeister Supreme
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Today my wife and I and some friends took a little trip down to Daytona. We went I-95 on the way down (SUCKS with no windshield!!!) and then came back US1. We were basically running between 65-75 the whole trip. We filled up before we left and as we were coming back I noticed I was getting really low on fuel and was thinking I need to stop at the next station. But I only had gone 115 miles on the tank so I figured I had a little more since I usually go around 130 before filling up and have never had to go to reserve.

WRONG! She started coughing and sputtering so I pulled over to a side road. I figured I would just switch to reserve and go to the next station that was less than a mile away. Wrong again. I switched to reserve and no crank. Tried and tried but no luck. I switched to off thinking something was just wrong with the petcock, no luck. So my buddy went on up to the gas station and bought a small can and some gas and brought it back to me. I dumped it in the tank, put the petcock on run and was good to go.

Now, I have two issues. I can't crank the bike up at all without giving it some throttle. And after a bit the idle drops and it stalls. My thought is that I probably got some crap from the tank in the carbs and it's clogging something, right?

The other issue is with the petcock. Why did reserve not work? When I got home I moved it to reserve and it cranked up fine, with me giving it some throttle. But any thoughts on why it will work off of reserve but not when it seems like it should? Could there be something wrong in the petcock so that reserve is acting like normal run and vice versa?

I really don't want to pull the carbs off but I have been contemplating doing an ear shave. If I have to pull the carbs to clean them I might as well re-jet them and pull off all the emissions crap while I'm in there I guess.
Glad you got the bike running again and got home ok with the wife. :)

Several times you use the term that the engine would, or would not, "crank" or "crank up".
To me that means the starter motor would not crank the engine over. In your situation that seems illogical.
Just running out of gas should not affect the electrical system of the starter motor.

I think what you are actually trying to say is that even though the starter cranked the engine over, it would not start and run.
Is that correct?

I had a similar experince with running out of gas and the petcock "RES"(erve) function not working.

As a rule I refuel before I have switch to reserve, but mistakenly thought I could make one more commute to work and fuel up on the way home one day last summer.

I have run on the reserve position purposely several times when the tank's fuel level was between 1/4 and Full, just to be sure it was functional and there was not any water or debris sitting down there waiting to plug the reserve pickup tube when I needed it.

On the day previously mentioned I believe the gas gauge was probably closer to 1/8 rather than 1/4 full when I fired the bike up after work, about 4 or 5 pm. It is about 6-7 miles to the card lock station where I usually fuel up. It was warm enough ride in a T-shirt and jeans, but not really hot, perhaps 70-75*F.

I had ridden about 2 miles when the engine began to lose power. It took a few seconds of the engine stumbling before I really believed I needed to switch to reserve and rotated the fuel valve/petcock lever ahead. The engine continued to stumble as I coaxed it on down a slight grade wondering how long it was going to take for the reserve gas to get to the carbs. The Vulcan had stumbled and coasted about another mile before I had to pull over and park on the side of the road.

Here is a question for the carb gurus out there. Should there be enough vacuum developed in the engine, to keep the petcock operational, when the bike is stumbling along at 15-20 mph in 5th gear and the clutch still engaged so the rear tire is keeping the engine turning over?

Seems like it should be enough vacuum to me, but the reserve function did not work on that day.
:(

I then opened the tank and rocked the bike side to side to determine how much gas was still in there. It seemed there was enough that the bike should start, but would not on either RUN or RESERVE. I QUIT CRANKING BEFORE RUNNING THE BATTERY DOWN, as that would have just caused another problem. After an hour or so, I finally got a gallon of gas to pour in to the tank and the engine fired right up and would run in either RUN or RES position.

I still do not know why RES would not pick up fuel when the fuel level got down to where I really needed it to work.

First thing I need to do is some re-testing by switching the fuel from RUN to OFF on a deserted road at 30 mph with plenty of gas in the tank and riding for a mile, more or less, until it starts to stumble. Then switch to RES to find out how long it takes for my engine to regain power. 3 or 4 similar repetitions should be enough to discover at least if it consistent.

Then if needed I will empty the tank and take it off so I can remove the petcock and examine it for any damage, dirt or corrosion I guess. (Also noticed earlier a little bit of paint chipped off the bottom of the tank right next to the petcock. Will be a good opportunity to fix that little problem too :))

If I leave the house now with less than a 1/4 tank of gas, I throw a 1 gallon plastic jug of gas in my saddlebag. It fits perfectly. I don't trust the "Bad Girl" not to strand me again until I figure out why she did the first time.

EDIT: OK. Four more guys have posted since I began this long winded piece. It seems from their experience that I may have just given up cranking the starter too soon when the petcock was set on RES(erve).

One winter I ran the carbs dry after pouring Seafoam in the gas. IIRC, in the spring I cranked the engine over for 30 seconds (timed) with a new MF-AGM battery, then let the starter cool for a minute or so before cranking the starter again. I think the engine started within 5 or 10 seconds during that second try.

In the event I do run the battery down, I do carry a set of light weight homemade jumper cables at all times.
Made from 10 feet of 16 GA lamp cord and a pair of battery charger clamps.
Weighs less than a pound, and rolls up small enough to carry in my pocket, but usually rides in the saddlebag.
Got the idea from Gadjet's fix it pages here:
http://www.gadgetjq.com/cheapcable.htm
 

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Discussion Starter #8
Thanks guys!

If I had been riding by myself I would have probably tried to reach up and switch to RES while riding, but with my wife on the back and it being dark I figured I'd just pull off to the side. I'll know better next time.

OlHoss, you are correct. When I was saying crank I meant the starter would crank but the engine wouldn't fire up. Maybe I didn't try it long enough. Being in the dark on a side road I didn't want to chance running down the battery and having bigger problems. I may play with that some more too like you were saying with switching to off and letting it run dry and then trying it with RES to see how long it takes.

I do run SeaFoam in my gas every 3 or 4 tankfuls to keep things clean. I'll give the flushing the bowls and "blowback" a try...maybe after church today. ;)
 

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Discussion Starter #9
Ok, well I can only drain the bowl on the left side. The drain screw on the right side appears to be stripped...that's not good. *sigh* Anyway, i drained the left side and blew back up through there. Fired her up and rode a little and everything seemed fine.

I turned the petcock to off and rode until she sputtered and switched to RES. After a moment's hesitation she picked right back up and away I went. So that makes me feel better about the petcock working correctly. I swtiched back to RUN and cruised back home.

I sat in the road in front of my house for a bit in neutral just to see what would happen and there were no problems. Turned around in the culdesac and got ready to pull into the driveway and just sat there a second. Slowly the idle drops..like you can hear it slowing down...and then it just stalls. After that, trying to crank back up I have to give it some throttle to get it fire up again and hold the throttle to get it to run. I can let out the clutch and take off no problem and it runs fine. But it doesn't give me a very warm, fuzzy feeling about stopping and expecting the bike to just idle normally. :doh:
 

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Discussion Starter #10
Ok...new info fresh in this morning. I cranked the bike up for the trip into work and it cranked and idled fine. Rode in the 25+ miles with no issues and the bike felt like it was pulling as hard as ever. I get to work and start making my way toward the parking garage and I have to go over 6 speed bumps: 4 are really speed mounds and 2 are more jarring bumps. Well I go over the first bump, no problems and then over the first two mounds, still no problems. Then I hit the second of the bumps and things start sounding funny...

The engine kind of bogged and when I pulled in the clutch to coast a little it stalled. I cranked right back up giving it some throttle and made it the rest of the way to the garage and got parked, but the bike ran like crap the whole way. Now, when I turned it off and got off, I could smell gas. Smells like it is coming from the right exhaust.

Does that sound like a stuck float? Could that explain the stalling and the idle slowing down until it just dies? Basically because it is just flooding itself out? Still makes me think it could be some crap that got to the carb because of the running out of gas and switching to RES. But it is just keeping the float from closing like it should. I sure wish I could get that right drain screw to open up so I could drain that bowl and blow up in there to see if it fixes it.
 

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Discussion Starter #11
I reckon I will just keep talking to myself and asking questions until someone that can answer some of them comes along. :)

I went out at lunch today and rode it a little bit. Definitely seems like something is flooding. It idles really rough and seems like one cylinder is cutting in and out...not sure which one...it was hard to tell. So anyway..my newest question:

Will it hurt to ride it home like this? I don't have a trailer to come back and get it, but I may be able to find one if it could do any damage to ride it home like this.
 

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see what the plugs look like, that will tell you a lot.

kenny
 

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Discussion Starter #13
The problem is I'm at work and of my tools are at home. So I guess at this point my most pressing question is can I safely ride the bike home (25+ miles) in this condition without doing any damage to it?
 

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The problem is I'm at work and of my tools are at home. So I guess at this point my most pressing question is can I safely ride the bike home (25+ miles) in this condition without doing any damage to it?
Hard to tell without hearing it. If it is too lean yeah you can damage things. If it is too rich, it will just load up with carbon and you will burn extra fuel.

Try running with the choke in the choked pos, if that helps, run it home that way.

I am not going to advise you to run it home and risk having it blow up and you get mad at me.

If it was me I would run it home, only because I know I could fix whatever happened to it.

kenny
 

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romeobravo172
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I agree with Kenny, try some choke and see if it runs better. When I bought mine I knew it had sat for some time and the idle jets were clogged (do not know if that is the correct name for them, they are the small ones) Mine ran fine by doing that. Pulled the carbs and indeed the small jets were totally cloged. If you find out that you are running extemely rich, be sure to ck your oil for fuel.
 

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Hard to tell without hearing it. If it is too lean yeah you can damage things. If it is too rich, it will just load up with carbon and you will burn extra fuel.

Try running with the choke in the choked pos, if that helps, run it home that way.

I am not going to advise you to run it home and risk having it blow up and you get mad at me.

If it was me I would run it home, only because I know I could fix whatever happened to it.

kenny
My nephews 05 does the same thing when warm and it needs a good carb cleaning for one thing . I know some don't agree with me on this but Iridium plugs and the pickup coil mod will help your hard start situation when hot. A lot of that problem comes from a battery so small it doesn't take much to crank it down low enough to keep the plugs fro putting out the proper spark,The faster the starter spins the engine the easier the 750 is to start. but that's for later

I would start by removing the tank and the petcock and see if it is clogged or there is gunk in your tank.You would be surprised at what you might find in there.if everything in there is clean move on to the dreaded carb cleaning.

If your problems started with running low on fuel ,I would almost guarantee you have water or other gunk in the tank.Also probably in the carbs now.

If you can get it started, ride home if you feel like it will make it there,or have friend with a truck pick you and it both up and haul it home.You need it there to work on it.
 

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Discussion Starter #17
The good news is she got me home. The bad news is she ran like ass anytime the rpms dropped below 3k and I had to keep on the throttle a little whenever I had to stop.

So, I figure the best thing to do is clean everything. I plan to pull the tank, drain it and make sure everything is clean. If there is any rust clean that out too. Pull the carbs and clean them really well too. Might go ahead and change to iridium plugs and change the oil while I'm at it. And since I'm going to have all that done I might as well get the parts and ear shave too. So much for the money I was saving up for some new handlebars and shorter shocks.

On the plus side, I'll get to know a lot more about my bike. I just put 7k of my own miles on her. I suppose I can get to know her better now.
 

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The good news is she got me home. The bad news is she ran like ass anytime the rpms dropped below 3k and I had to keep on the throttle a little whenever I had to stop.

So, I figure the best thing to do is clean everything. I plan to pull the tank, drain it and make sure everything is clean. If there is any rust clean that out too. Pull the carbs and clean them really well too. Might go ahead and change to iridium plugs and change the oil while I'm at it. And since I'm going to have all that done I might as well get the parts and ear shave too. So much for the money I was saving up for some new handlebars and shorter shocks.

On the plus side, I'll get to know a lot more about my bike. I just put 7k of my own miles on her. I suppose I can get to know her better now.
gettin home under it's own power is always a good thing:smiley_th
 

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The good news is she got me home. The bad news is she ran like ass anytime the rpms dropped below 3k and I had to keep on the throttle a little whenever I had to stop.

So, I figure the best thing to do is clean everything. I plan to pull the tank, drain it and make sure everything is clean. If there is any rust clean that out too. Pull the carbs and clean them really well too. Might go ahead and change to iridium plugs and change the oil while I'm at it. And since I'm going to have all that done I might as well get the parts and ear shave too. So much for the money I was saving up for some new handlebars and shorter shocks.

On the plus side, I'll get to know a lot more about my bike. I just put 7k of my own miles on her. I suppose I can get to know her better now.
glad you made it home, did you try some choke and see if it made a diff?

I would be careful doing too many things at once. You know you have a problem now, I would fix that first, get it running right then if you want go with all these ear shaves and special plugs. If you do everything and it gets worse, then what would you do?

One step at a time especially when you have a problem.

good luck

kenny
 

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Mine had similiar symptoms and I was getting very frustrated. Couldn't keep it running without some throttle at a stop. Wouldn't idle and ran like crap, until I hit about 3K and then would take off like a scalded cat. Didn't ride for about 10 days while studying the forum and testing everything I could find to test. Also gave me some time to gather supplies.

I finally took the carbs off and did a thorough cleaning, upped the jets to 142/42's with two shims under needles. With carbs off, I followed the ear shave sticky and have not regretted it one bit! Cleaned everything up under the tank while it was off, rerunning some wires I had threaded through there during earlier mods. Looked ALOT better. Much cleaner and done of purpose, rather than in haste.

Very pleased with results, as I am sure you will be too.

Here's link to my post with some pix of results: http://www.vn750.com/forum/showthread.php?t=23677
 
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