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I've spent a few hours the last couple evening digging through old carb archives, trying to find some guidance on my 2003 VTX carb issue. I have a long thread that has worked out a few bugs, but I'm still have issues. Looking to change my approach a little.
My current problem is the bikes wants to sputter and die at highway speeds. It happens around 85/90 mph. Closer to 85 when I'm going up a incline. I did put seafoam in it, and ran it about 100 miles, no real change.
It does it in 4th and 5th gear. The bike sputters and continuously pops (exhaust) like it's running out of fuel. You let off, and when the bike slows down around 65 it "catches back up" and runs okay. Get back up to 85/90 it'll do it again. I have a couple of times hammered on it and its gone up around 95/100 and still run okay, but those are few and far between.
This leads me to believe there is some problem in a transitionary area in the carb. Like, from moving from Pilot to main jet or something. My initial though was the fuel supply to the carb wasn't enough, but WOT in 1st and Second has to use way more fuel than highway cruising in either 4th of 5th.
The carb was fully cleaned and chem soaked last year middle of season. The carb is clean. The bike will run WOT in the first 3 gears just fine. I've brought it up to about 40 in 1st, around 60 in second, 80 In third all the way open on the throttle and it doesn't miss a beat. (Now, after researching the last couple nights I realize I could go higher in second and much higher in third. And when it's back together, I plan on trying that). There is no fuel strainer in the inlet of the carb, as this is a 2003 and it had an in-line fuel filter between the tank and the pump.
I've taken the bike apart to remove the carb bowl, and look at the float. I was wondering if maybe the float is sticking.
I've checked vacuum lines, removed, inspected the ends, and replaced. Everything looks okay. Is there some vacuum actuator, or spring controlled something that could be causing this?
It is a 2003. and the fuel pump was disconnected. The petcock is only 3 years old, but it's a 2003 version without the vacuum. I've checked it, and when its On or on reserve it's fully open. There have been countless people on the forums that ditched their fuel pumps and their bikes ran fine, but I wanted it here just for reference.
I checked the black rubber diaphragm that raises the needle last year when this was happening, and there are no cracks, tears, etc. I used a LED light in the dark all around it, multiple times, not light shinning through. I'm at the point, I don't know what else to check.
This is probably some stupid little thing, but I need a VTX expert to weigh in.
My current problem is the bikes wants to sputter and die at highway speeds. It happens around 85/90 mph. Closer to 85 when I'm going up a incline. I did put seafoam in it, and ran it about 100 miles, no real change.
It does it in 4th and 5th gear. The bike sputters and continuously pops (exhaust) like it's running out of fuel. You let off, and when the bike slows down around 65 it "catches back up" and runs okay. Get back up to 85/90 it'll do it again. I have a couple of times hammered on it and its gone up around 95/100 and still run okay, but those are few and far between.
This leads me to believe there is some problem in a transitionary area in the carb. Like, from moving from Pilot to main jet or something. My initial though was the fuel supply to the carb wasn't enough, but WOT in 1st and Second has to use way more fuel than highway cruising in either 4th of 5th.
The carb was fully cleaned and chem soaked last year middle of season. The carb is clean. The bike will run WOT in the first 3 gears just fine. I've brought it up to about 40 in 1st, around 60 in second, 80 In third all the way open on the throttle and it doesn't miss a beat. (Now, after researching the last couple nights I realize I could go higher in second and much higher in third. And when it's back together, I plan on trying that). There is no fuel strainer in the inlet of the carb, as this is a 2003 and it had an in-line fuel filter between the tank and the pump.
I've taken the bike apart to remove the carb bowl, and look at the float. I was wondering if maybe the float is sticking.
I've checked vacuum lines, removed, inspected the ends, and replaced. Everything looks okay. Is there some vacuum actuator, or spring controlled something that could be causing this?
It is a 2003. and the fuel pump was disconnected. The petcock is only 3 years old, but it's a 2003 version without the vacuum. I've checked it, and when its On or on reserve it's fully open. There have been countless people on the forums that ditched their fuel pumps and their bikes ran fine, but I wanted it here just for reference.
I checked the black rubber diaphragm that raises the needle last year when this was happening, and there are no cracks, tears, etc. I used a LED light in the dark all around it, multiple times, not light shinning through. I'm at the point, I don't know what else to check.
This is probably some stupid little thing, but I need a VTX expert to weigh in.