Do you still have the "T" in the fuel vent line in place?

I ask because I removed it from my line and had the same stalling problem, not the gas volume/venting issue. I replaced the "T" and ensured it was clear, and I blew some air through the vent hose to make sure i could hear air moving in the tank. And the stalling problem ended.

Good Luck!

 

I agree with Helmking's idea. Make sure your vent line is clear and not blocked or pinched. Also make sure the anti-siphon t-fitting is in place and not clogged or pinched.

 

I'll check that tonight before I replace the gas tank cap.

 

I learned from first hand experience not to leave that line unplugged when I did my Pair Valve removal and inadvertently left that line disconnected. The bike didn't stall though, it ran out of gas when I went around the corner. I'm sure the "Run" pickup got uncovered and the carb went dry, which is why it started and ran fine on the "Reserve" setting. I'm just stumped as to why 1.63 gallons filled up the tank, when no fuel was visible in the tank when I went to fill it up at the gas station.

 

Check to make sure that the gas cap sealing gasket is in good working condition. The gas cap is a non vented cap and needs the internal tank vent in good working order to keep the tank from expanding or collapsing due to temperature changes and to vent dry air into the tank as the fuel is removed while the engine is running. The reason for the non vented gas cap is to keep water from getting into the tank if the bike was left out in the rain, If the gas cap has a good seal to the cap rim than there is no reason to replace the cap. Also, if you fill the tank on a cold day and then park it in a warm area the fuel can be forced out of the vent line as when the cold fuel warms up the liquid will expand and since the tank is not vented at the cap it can flow the excess volume into the vent system and gravity feed to the ground.

 

The gas cap seals tight when push down the cap to lock it into place. I'm wondering if the heat from the engine is causing the fuel to expand and go out the vent, but then everyone would be having the problem I'm experiencing. I typically fill the tank to the bottom of the fuel tank neck, which is what the owners manual say's is the correct amount. Am I filling the tank too full?

 

Are you on the side stand while fueling or holding the bike straight up? I generally fuel with the bike on the side stand until I see the fuel touch the bottom of the neck on the down side,I have never had a problem with fuel leaking out the overflow, also I am not one of those persons that has to get the last drop that I can possibly get in there (besides I generally have 150 mile kidneys and the bike can generally go over 160 on the main tank and another 30 to 40 on reserve). I generally don't fuel up at the end of the trip since I live out in the country but that is not a hard and fast rule, if the bike is experiencing changing weather (cold on the day I am filling up and maybe a major warming trend before I will ride again I will leave the level a little lower, course, living in the country, the closest gas is about 6 miles away and pretty expensive so I generally fuel up at Costco or one of the truck stops a lot farther from home hence, the reason for filling up early on my trip out. I do try to fill the tank when it looks likely that I may not ride again before winter and always add Seafoam additive to that tank at about 1 to 2 ozs. per gallon of fuel that the tank can hold (I take it with me in a small bottle and add it before I start filling up)/

 

What others have mentioned.A blocked/pinched fuel vent line.I watch a lot of videos about these VTX bikes when browsing youtube.This one is an 1800,but it could happen on 1300's too I imagine.But since this guy on youtube blew the blockage back into his tank,you have to wonder where it went...lol

https://www.youtube.com/watch?v=E8UId4XveaY

 

I generally always fuel up on the ride out, but since I had run the tank down to reserve I decided to put in only two gallons on the way home. Put the fuel in on the side stand this time, because I thought two gallons wouldn't even come close to topping it off. Still can't figure out why it only took 1.63 gallons to top it off. I'll check out the vent tube for blockage this weekend. Is there a vent line and a drain line? I only recall connecting one vent line (right side rear of tank) when I've taken the tank off. Seems like a clogged line wouldn't allow fuel to pass through and drain onto the ground? The bike runs fine, just drains fuel when full and the engine warm.

 

I generally always fuel up on the ride out, but since I had run the tank down to reserve I decided to put in only two gallons on the way home. Put the fuel in on the side stand this time, because I thought two gallons wouldn't even come close to topping it off. Still can't figure out why it only took 1.63 gallons to top it off. I'll check out the vent tube for blockage this weekend. Is there a vent line and a drain line? I only recall connecting one vent line (right side rear of tank) when I've taken the tank off. Seems like a clogged line wouldn't allow fuel to pass through and drain onto the ground? The bike runs fine, just drains fuel when full and the engine warm.

Just a thought here but is it possible that the lower part of the main tank pickup tube could be fouled with sediment causing you to have to go to your reserve tank pickup when there is still fuel in the tank above the reserve level?

 

Yes, only one tank vent line. Rear right side of tank on underside. This vent hose follows a less than straight line and drains out bottom of bike in front of rear wheel. A bit (~18 inches) upstream of the end of the vent line is supposed to be a tee in the vent line connected to a short (~6 inch) anti-siphon hose section.

 

I'll probably replace all of the line, but I'm especially curious about the "tee in the vent line connected to a short (~6 inch) anti-siphon hose section". Maybe this anti-siphon hose is my problem. This is on the to-do list tomorrow!

 

The "tee" should be located at the highesr point of vent hose routing and open to atmosphere! Make sure the vent tubing connected to the "tee" (downstream of tee) and hanging down is open back to to the "tee". Do not assume, blow back into it and check that it is passing (pressure venting at open port of the "tee") at the"tee" port. You could also pull a vacuum and check, whats best for you. Maybe you had the gasoline nozzel and shutoff valve sensor too deep in gas tank shutting the gasoline flow off prematurely? I hope this makes some sense. Wishing you well.
atriot:

 

Is the tee really at the "highest point of vent hose routing"? I thought the point where the vent line attaches to the tank is the highest point?

 

Highest point after connecting to the tank albiet that would be an excellent point to vent, but wouldn't want fuel inadvertently dumping top of the engine and upwind of the seat. Probably would create additional problems located there removing and installing the tank for other maintenance needs. Wishing all well!
atriot:

 

Update: I was out of town on business and just now can update my thread. I removed the vent line and verified the T was not obstructed. Really stumped at this point and guess I'll just not fill up the bike, unless I'm planning on leaving immediately for a ride. I took a 70 mile round trip yesterday along River Rd. in New Braunfels and the bike ran great. Of course the bike didn't vent any fuel when I got home, because I had burned off ~1.5 gallons. Is there supposed to be any type of factory heat shield under the tank to keep the tank from getting heat soaked from the engine? That's the only thing I can think of at this point that's possibly causing the tank to vent out fuel.

 

Nope, no heat shielding at all!!!!