06 FLHT CV 40 carb. At half tank the bike stops getting fuel. I get about 80 miles then I have to put in 2.5 gallons. I pulled the petcock, screen is clear. Checked the vacuum line, no issue that I can see. Also checked the tank vent (under cap), not plugged. Bike runs fine until that half tank.

 

Fuel flow stopping at the same level each time sure sounds like crap on the petcock fuel screen...

Have you tried loosening the fuel cap when the problem occurs?

 

Friggin weird, I just burned 3.8 gallons without issue. Maybe when I removed the petcock for inspection it flushed something off the screen?

I did test the gas cap vent. I'm not going to admit how I did it, but I'm sure you get the idea.

 

I ain't assuming that you ain't aware of reserve capacity...but does your your petcock have a a reserve setting?

I have measured the tank capacity on my 2001 FXD and honestly right off hand I don't remember the exact usable capacity to quote, but I do remember that it holds just over 3 quarts of gas in reserve and it seems to me it is like 3+ gallons available in the main setting for MY tank...and I also know from experience that when that gas gauge gets down to that red mark, it's gonna spit and sputter and bitch until I reach down and twist the petcock up to reserve...and head for the nearest gas station...

 

You haven`t told us if you have fuel flow when the valve is switched to reserve...

 

One time the reserve setting got me the 10 miles I needed to get to a station (switched it before the bike totally died), another time it died on me and when I switched to reserve it had a hard time starting and stumbled the .5 miles to the service station. In both instances it returned to normal after refueling.

Strange thing is that the next tank I ran 100+ miles and burned 3.8 gallons as normal without issue. Maybe when I removed the petcock something flushed off the screen? I have a Pingel on the way.

 

I've seen the tank crossover line plugged. When that happens, there is gas in the bike but none to the carb.

Used to see it a lot with tanks that got painted it if something got into the tank.

 

I'll be sure to check that when I drain the tank to install the petcock

 

I installed the new petcock today, made an observation that I thought I would share: my OEM petcock was flowing fuel even without vacuum. I had the vacuum line disconnected and it flowed on both on and res. I installed a Pingel that doesn't take vacuum so I guess I have eliminated that issue. Oh, and the crossover line is flowing fine.