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Premium Member
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Discussion Starter #1
I'm new to the forum, and looked all night for a similar issue but couldn't find one, so I'm hoping someone can help.

'98 VN750, CA Model. Carbs rebuilt about a year and 1500 miles ago (previous owner, I have the receipt though)

At about 70mph last night the bike randomly Bottomed out on RPM's. It did this twice within about 2 minutes, and I had initially thought I had throttled off a bit and not realized it, so I opened the throttle more, and a second later rpm's and everything was back to normal. About 2-3 miles later, rpm's bottomed out again, and the bike stalled out on the freeway. Thankfully I was able to get on the shoulder quickly without any traffic issues, and the bike started right back up without an issue. I let it idle for a few minutes, no issues. I proceeded the last few miles home without any other issues. I started it up again about 20 minutes later, just to let it idle, and a couple of minutes in, it bottomed out, recovered, then the engine quit 15 seconds later.

I have a little less than a quarter tank of fuel, and my first thought was maybe just bad fuel/dirt in the tank. Regardless, having stalled on the freeway I'm parking it until I can figure out what is going on. If anyone has any experience with this, links, ideas, or other questions about the bikes behavior (lights did stay on when it stalled, thankfully seeing as how it was about 9PM). Please let me know.

Much appreciated in advance.
 

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Old Truck Junkie
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4,133 Posts
It could also be your ignition switch needing cleaning.
Another thing to check is the vaccuum line from the petcock to the carb.
Also check that the right front spark plug is not grounding to the throttle cables.
You may want to add a little bit of water remover to the fuel tank.

Welcome to the group.
 

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Giggity!
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also check that the little hose on the right Ear (filter) isnt bottemed out or all the way out.
Preventative. Some folks have cut the end of that hose at an angle to prevent it from being sucked up against the back of the air filter housing.
 

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Registered
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Yeah.. I had sort of the same issue but mine had backed out of the filter and at higher speeds it would almost kill the engine.. pulled my hair out on that one!
 

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The POOGS doesn't answer why it would die after you started it up at home and let it idle. Sounds more like a dirty ignition switch or the grounding at the front right plug wire on the throttle control cables.
 

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Discussion Starter #9
The bike is a CA model, does that make a difference in fixing a POOGS? The threads don't seem to say. I've been trying to check everything today, and so far nothing seems to be wrong, I started it up, and let it idle for a good while.. didn't seem to do anything wrong now, but haven't ridden it yet, may try tonight.
 

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You say you have 1/4 tank of gas? Were you on main or reserve? seems about the right level for that swap to reserve. (Just a thought):doh::wow:
 

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The bike is a CA model, does that make a difference in fixing a POOGS? The threads don't seem to say. I've been trying to check everything today, and so far nothing seems to be wrong, I started it up, and let it idle for a good while.. didn't seem to do anything wrong now, but haven't ridden it yet, may try tonight.
The procedure to clean the gas cap vent for non-CA and CA models should be similar (I assume). However, CA-model gas tank vents may include (depending on model year) a charcoal canister, tubing, valves, etc. Follow the instructions for the non-CA model to to check the gas cap vent first (where most of the problems occur). Deal with the CA-specific tank venting after.

Again, if it is POOGS, then it is easier to fix/(eliminate as as possible cause) then digging into the fuel/carb or electrical systems. For reference, POOGS strikes at higher frequency when the fuel tank reads 1/2 tank or less (i.e., more air space = more vacuum).
 

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Discussion Starter #13
So I cleaned out the gas cap vent and put some water remover in there, and took it for a ride, rode fine for a good few miles like usual, then constantly dying. I haven't had a lot of time, so I haven't checked out a lot of things, but I do have a follow up question. I assume, like most bikes that if you turn the petcock to off while the engine is idling that it will kill the engine? I tried that, and nothing happened at all, engine continued to idle smoothly. I'm a novice at best when it comes to trying to work on bikes, and I don't have a full understanding of carbs yet. Bought the Essential guide to Motorcycle Maintenance, and trying to learn from that.


Thanks everyone! You have all been a big help, and hopefully I will find the time, and figure out what's going on so that I can be back out on the road!
 

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Premium Member
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Turning the bike to reserve should not affect the engine at any speed unless the reserve screen on the petcock is clogged, the bottom of the tank is full of water or crud or the tank is empty.
 

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Linkmeister Supreme
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I turned it to off though, I thought that should have killed the engine?
You may have misread the markings on the petcock. For "ON", the lever you turn is straight down in the six o'clock position. "OFF is the lever at 3 o'clock, and "RES" is the lever at 9 o'clock. The little protrusions on either side of the lever head can be misleading.
 

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You may have misread the markings on the petcock. For "ON", the lever you turn is straight down in the six o'clock position. "OFF is the lever at 3 o'clock, and "RES" is the lever at 9 o'clock. The little protrusions on either side of the lever head can be misleading.
I made this mistake just yesterday. Then i put it on reserve and/or on...oops!
 

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Discussion Starter #20
Better luck today with that understanding, the engine did die after a few minutes. So where I am at now is:
The bike starts and runs just fine from a cold start, idles and warms up well, and then will run (between 25-40 mph) for a few miles before it starts constantly dying every other block or so. Sometimes I don't have to do anything other than pull over to restart it, other times it seems to fight me, and I have to turn the key to off then back on for it to again start no problem. It'll run and drive for a minute or two, then die again. lights remain on when it dies. When I get it back to my garage and let it idle a bit, it still will die occasionally. Seems to be an issue that only occurs when the bike is warm, but I've been strapped for time, and haven't gotten much to play with it. I cleaned out the gas cap vent, no blockage there, everything went back together smoothly. It's a CA model, so I have the breather box to fuss with, but I actually haven't been able to locate it yet. When it does die, it doesn't appear to stutter or anything, just bottoms out and dies. I put in some carb cleaner, ran it and it didn't fix the issue. Have also ran it on both reserve and primary and made no difference.

Any thoughts? Thank you everyone, I'm not the most knowledgeable guy, just trying to do my best and learn while I am at it.
 
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