under tank hose for communicating vase (Link pipes) (SOLVED)

[klingklang]

Many times I've notice at highway speed that I am using the fuel faster in the pump section of the tank faster then the rest of the tank would supply.  It is surely by  these fuel pipes under the tank. At extreme,  my bike stall running out of fuel after a while on the empty light,  I stop on the side,  close the bike and wait 5mins to get some fuel to a point that the empty light go off.  I've already changed those hoses to be sure there clean and freeflow,  did the fittings too and take care they are not stuck somewhere.  Now I am tired.  I don't like the about or maybe situation. Like to know if this happen to others and is some have an idea to solve this.  I am thinking of a bigger ID pipe and fitting if I could.

[motoOzarks]

Clogged filter?

[klingklang]

Sorry, maybe I did not explain well. Nothing to do with fuel pump or filter.  You have under your tank 2 link pipse that move the gas from the front lower bulge par of the tank to the under seat section. (communicating vase) and they don't supply gas transfer fast enough on long non stop move.  You need to stop, unless the engine will, to allow some fuel to move where the pump is. Like to see if there is a way to modify that to get better steady level.  bigger fitting bigger pipe. I am alone to notice that. This is really annoying when you have long distance to travel.

[motoOzarks]

Never heard of such an instance before

your problem is somewhere else

Is your cap venting?

[John Stenhouse]

Those pipes are fitted to every Girly bike but as far as I'm aware you are the only one to report this problem. It could be a tank vent problem, or maybe the fitting of your tank, are you missing any spacers from the front of the tank, if it's too low there the fuel may stay at the front untilyou get off the bike.

[klingklang]

I have the bike for 10years and always did that.  Changed the link pipe, cleaned the fiting, diasassemble the cap itself, new gasket and cleaned it many times in the last years as I did also for the air and drain pipse. I even tried leaving the cap open. niet,  cant see.  Nobody else have that? Fill the tank and go to the highway at 120-140km non stop till the light come or go on till the engine stop.  You stop the engine(when not killed itself by running out of fuel) and wait. After restart,  gauge needle is just few millimeters above the red. I've changed the gauge long time ago and cant be that because the bike run out of fuel and the gauge itself cannot stop the engine as far as  I know.  It is simple as at FWOT the gas is running lower as it really is.

oh ,, I ve also checked for compressed or kinked pipes.

[John Stenhouse]

How far are you going before it stops?

[Bixxer Bob]

This is beginning to sound like crank sensor......

Did you actually look inside the tank and see the fuel level different between the back and front?  If the pipes are clear and the problem was as you think, it'd start pretty much straight away.  If it needs a few minutes, like to cool down, the crank sensor is in the frame.

[Sin_Tiger]

Is it possible to nip the pipes during a tank refit?

[Bixxer Bob]

Not really Sin,  but then again, as with everything, folks will find ways.

If it really is fuel starvation, and I'm not convinced yet,  I think it's more likely a fuel pipe gone soft and sucking flat, a blockage somewhere, or a failing fuel pressure relief valve.  It could be picking up, or have picked up crap which is blocking the filter, I've even heard of the link pipe between the fuel pump and the filter leaking and causing problems.  Without seeing it, it''s hard to tell.

[motoOzarks]

With a low fuel level could the pump overheat and take a time out?

When your thinking your waiting for fuel you are instead waiting for the pump the cool?

Is the pump getting the correct voltage?  Meaning enough for it to work when kept cool in the fuel and then getting hot as you run it low ?

One of these pipes should keep the bike running.  If it starved under acceleration or wot it should stay idling rather than die and not restart.

[klingklang]

How far are you going before it stops?

On day to day  or normal backroad I do between 325 and 350km of autonomy.  In rare occasion I went to 400. But on non stop ride,  the ligth go on at around 250 an the bike stop empty around 275.  After stop and way,  I can reach an another 30-40 km sometime more but at this point you'll understand that I am not gaming with the fuel unless I have my rotopax fuel jerry can.

For the others question,  I had changed the link pipe like 2years ago with sturdier fuel pipe. Not to link and take special attention when I remove an put back the fuel tank.  I've shot compressed ai in the nipple firing....

... pause to get some rest. Take to much energy to write on a tablet.... Down I hate it

Ok.  Always thought  it was a design flaw and I was not alone.  You know the high end dealer mechanics telling you "they all do that"

I am trying to understand how a pump or a crank sensor that work normaly well will do something that make you run empty at both the engine and fuel gauge then bring back fuel like magic after. 

No at this point I can't see fuel in .

At first,  I also pin pointed a air pressure/vacuum in the tank but running the tank cap open did not change anything. Is the reverse could do something,  mean to much air.  ? 

Thanks guys for your help.  I'll wait on my computer to answer next.  I'am typing 3letters an need to go back twice to correct..

[motoOzarks]

Have you checked for fault codes?

One more post and you're a Puma!!!

[klingklang]

no fault codes seen on tuneboy.  no, it can't be mechanical,  It is as simple as fuel transfert inside the tank.  At a certain speed I am just taking gas faster than it fill the pump portion in the tank. Will try to get in the tank with a cam later this winter. 

11years to be Puma...good. I'm not the one that bothers most

[Sin_Tiger]

Tricky  I can see where you're heading BB and it can't be ruled out at this stage. MO good point.

To be sure of this you need to test it under load and when hot. Not easy or safe to do wile riding and an expensive exercise unless you happen to have your own rolling road. Only real way to verify the pump performance is dropping off is to T in a pressure gauge and monitor it. It's possible the windings are starting to fail under stress, alternatively the mechanical side might be getting a bit worn and not able to keep up unless it has a good positive head on the suction, or a combination of both.

I wouldn't normally advocate it, as I prefer to know 100% what the issue has been but in this case I'd be very tempted to replace the pump unit if you know the filter is good.