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Discussion Starter #1
Hey all. So the fork situation I had earlier is finished with, No more leaks. Now the next and probably final issue; I don't think I'm letting it idle on choke long enough but the bike seems to fire only on one cylinder or is starved for fuel after a half mile riding, it feels like POOGS but never stalls. The other thing is after 23 miles my gauge reads at half full tank. What gives?

This is my first bike over 250 by the way so I may just be doing bad habits that the Rebel taught me.
 

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Has the bike sat for a while? Sounds like a clogged float needle if it's only happening on one cylinder. Tap on the carbs and maybe toss some seafoam in the gas? Realistically these bikes should get around 35-40+ mpg if they're not re-jetted, even with a twisty wrist. Stuck closed float would cause one cylinder to starve for fuel, but it'd have to be flooding like crazy and running stupid rich to eat half a tank in 23 miles. Then again, the gas gauge on these isn't the most indicative of actual fuel level. I typically count on 120 miles on a full full tank (all 2.7 gallons, filled to the bottom of the filler neck), but the gauge reads empty probably around 90-100 miles (with about 1/2 gallon left, I reckon).
 

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No answers here. . . .:confused:

I would "punt"! I've used Berryman's B12 fuel additive for cleaning carbs with some success in the past. I'd try that first. It's a fuel additive that you put in the gas tank. Bought mine at Walmart.

https://www.walmart.com/ip/Fuel-System-Cleaner-Injection-Cleaner/16817404

If it doesn't work, you're only out $6. Never had much luck with Seafoam, but some swear by it. . . .

Chances are if it's running on one cylinder, expecting any additive to work may be a pretty big ask. To my mind, a complete blockage is going to keep the additive from getting where it needs to be to do its job.

UberTall's diagnosis sounds like a problem I had in the past. I took a tank in to get painted, and when it came back I added a fuel line filter. Painter must have primed it with no covering over the fill hole because the filter and float valve were getting filled with crud that looked like primer "dust" to me. Took getting stranded with a bike that wouldn't run several times for that to work itself out! Not fun.

That said--could be an electrical issue with bad coil, or spark plug wires, or, ???? Then the fuel additives are going to do nothing for you. Maybe someone else will come by with another idea.

GDI
 

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Discussion Starter #4
I probably should have mentioned she just got out of the shop a couple weeks ago! They cleaned and repaired the carbs to be brand new and the tank got a new coat inside. So it shouldn't be an actual fuel delivery issue, if it is I think that shop screwed me.
 

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Did this happen just one time, or repeats every time you take the bike out?

For now, I would say look at the plugs and let us know what color you find on them. Can also check the spark, note color and strength. Is the spark blue with a quick *snap*, or orange/yellow and just sort of lights up?
 

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Discussion Starter #7
Not sure yet, will give it a look once I get home! I'll let it choke until it revs up to 3k on its own then see if it does it again.
 

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Discussion Starter #8
I pinpointed the issue down to a blocked gas tank cap vent and non-existent carb vent lines. Would not having carb vent lines cause this kind of power loss and crap? I would imagine so.
 

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I pinpointed the issue down to a blocked gas tank cap vent and non-existent carb vent lines. Would not having carb vent lines cause this kind of power loss and crap? I would imagine so.
Wind hitting the vents will cause bogging, because the positive air pressure prevents fuel flow into the bowl on a gravity feed .

Vent lines need to run into dead air space. There's a spot to put the hose onto either ear (air filter box), or if earshaved, the blank 'nipple' on the fuel gauge sender cover (bottom of gas tank) is the best place. Even vent lines with a filter on the end can have problems with wind.

Hose plugged into the ear needs cut at a 45° angle so it doesn't block off against the back wall of the ear.
 

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Discussion Starter #10
I appreciate the response Spockster! I'm gonna be in for hell getting these hoses on (because I refuse to remove those carbs. Got one hose on, just got the other now!) but I'm glad it'll solve my bogging issue. I already fixed the POOGS issue!

And since I'm scatterbrained and can't collect my thoughts properly, I accidentally created a new issue! I used 3M Trim/Emblem Adhesive on the tank for my emblems and it ate the very custom paint job in the emblems' spots. I'm gonna be getting a decal for it to try and cover it up and make it work. Before I start, anyone have any ideas on that one?
 

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Thanks and you're welcome.

That's sort of odd with the 3M eating the paint. Was the paint fully cured yet?

I see on the other thread you plan to sand it. That's about all I could advise. Maybe try painting a test piece, let cure a few days, see if the 3M still damages the paint.
 

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Discussion Starter #12
Will do. I think it was fully cured but I can't be too sure. The friend who gave it to me painted it himself with Maaco paints so that's probably PART of the problem...
 

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Discussion Starter #13
I don't know if anyone will see this but I don't want to make another post and spam the forums. New problem: Bike slogging/stuttering really bad around 4-5k RPMs. I suspect it's the carb vent lines I recently put in not being routed right, but I put it into the duct in the rear of the right ear and don't see another spot for it. POOGS issue has been dealt with but now it won't run right and I don't know why. Air filters also are not new and I'm unsure if they're bad or not.
 

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Discussion Starter #14
ALSO! The petcock (the Yamaha single port one) is still flowing even in the on position, when I know it shouldn't be.
 

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I don't know if anyone will see this but I don't want to make another post and spam the forums. New problem: Bike slogging/stuttering really bad around 4-5k RPMs. I suspect it's the carb vent lines I recently put in not being routed right, but I put it into the duct in the rear of the right ear and don't see another spot for it. POOGS issue has been dealt with but now it won't run right and I don't know why. Air filters also are not new and I'm unsure if they're bad or not.
Do you have the hose plugged into one of the holes at the top right or bottom right of this picture?

 

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No, I actually had it in the square hole. I'm assuming that is definitely wrong?
Yup, still getting air disturbance there. Cut at a 45° angle and push it deep into the round hole at the top. Push it all the way in, the angle will keep it from getting blocked off.
 

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Discussion Starter #18
Alright, gonna do that here in a sec and take a test ride in a few hours. I hope it works Spockster, I wanna take her on her first club ride!
 

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Discussion Starter #19
Well it ran fine for a solid hour then started bogging down badly as the day went on. Eventually it wouldn't make power at all, bog down then continue again while I was on WOT, bog down again and so on. Then once I slowed down enough it shut off and wouldn't start up again for a little while. While it sounds like POOGS, it shouldn't be unless I missed something during cleaning. The vent hose is fine and cut, and in the proper hole too. I don't understand at all. It's also backfiring pretty badly on decel and with choke on. I don't want to go back to the shop, they were supposed to fix this the first freaking time.
 

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Well it ran fine for a solid hour then started bogging down badly as the day went on. Eventually it wouldn't make power at all, bog down then continue again while I was on WOT, bog down again and so on. Then once I slowed down enough it shut off and wouldn't start up again for a little while. While it sounds like POOGS, it shouldn't be unless I missed something during cleaning. The vent hose is fine and cut, and in the proper hole too. I don't understand at all. It's also backfiring pretty badly on decel and with choke on. I don't want to go back to the shop, they were supposed to fix this the first freaking time.
If it was POOGS, you could have opened the gas cap and it would fire right back up.
 
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