Fuel delivery problems on VFR750FG

Alright, more problems with my VFR's.

Had the number 2 VFR conk out on me on the way to work the other day- had to take this bike because #1 valve stem would not hold air. It acted like a fuel pump/relay problem- eventually sputtered out after the bowls ran out of gas about 8 or so miles of riding to work- pretty much all highway. The battery was on the way out so I had to order the wrong one when I looked at the wrong box for the battery number- the battery was for the CB750.

I checked the fuel pump and ran the volume rate test- passed.

I did some checks on the relay and another one I had lying around and got the following readings with my Fluke.

ohmmeter test showed about 5.2 megaohms one way and 0 ohms the other on the black and blue connections. When I ran the diode test one way showed about 2.11V and zero the other way on the black and blue.

That test means they test out OK since they are basically 3 terminal relays- the yellow green wire is just the trigger, right? It showed zero response when I tested it against the other connections.

I blew out the gas cap to try and make sure it was venting correctly, I don't think that is the problem there. Filter looks fairly clean from when I put it on a year or two ago and the tank is clean.

Any suggestions as to what the culprit is?

 

What about your carb vents? Plugged or pinched hose? Your right about how the relays work. One leg has 12v, one goes to ignition box(is trigger when coils fire) one supplies 12v to pump after trigger fires.

To test you can make sure carbs are full of gas. Take hose going to carbs, pump output, and put in a container. Start bike and see if pump pumps. It should if relay is working properly. I doubt you could go 8 miles without the pump working. Did the bike run fine when it had fuel? Is tank flowing fuel properly when the petcock is opened?

 

Where are the vents in these carbs? I have a non-CA set and I cleaned them out pretty well about a year ago when I changed the bowl gaskets and the intake rubbers. Clogged vents should not really be an issue here.

I'll compare these relays against the one in #1 to see if I have the same numbers there since that bike does not seems to have fuel issues save leaking fuel out the carb bowls.

 

OK, tested another spare fuel pump relay in my box o' parts and it tested about the same as the other two.
Whatever the condition is that is causing this lack of fuel at highway speed I remember the time I rode before it conking out the bike conked out on the road then too. I though it was because I had the choke partially on (Maybe 1/4 choke) but couldn't see that it was on because it was dark out but thinking back on it now it was the beginnings of the fuel delivery problem.

This is starting to drive me nuts because this bike is the better cosmetic bike of the two.

 

Fuel tank vent clogged ???

 

Have you verified this: "To test you can make sure carbs are full of gas. Take hose going to carbs, pump output, and put in a container. Start bike and see if pump pumps."

Are you getting fuel out of the pump when the bike is running yes or no?

 

I had a battery brainfart a couple of days ago when I grabbed the wrong box for the model number when ordering so I am waiting for the new battery to charge before I test that Grey.

Are you talking about a cap vent Squirrel? I blew a bunch of air in every damn place I could on that cap when I removed it from the tank, if it had any crud in there it hopefully got blown out. I also blew on the hose that runs down the right side by the battery overflow hose, and blew air through it- not obstructed.