Stutter, Burble, Miss,???

[Chuck K. #5458]

Have had a miss,stutter type problem on occcasion. Usually occurs at highway speeds and  from 80 to 100 miles into a full tank. Feels like I need to switch to reserve but the miles don't justify it. Sometimes I can ride through the problem and it clears up and other times I have to switch to reserve, which seems to clear up the problem. After some miles I can again switch back to normal on the petcock and things seem fine. I do not have a kinked vent line. I run a Honda petcock with the vacume function disabled and am NOT interested in changing to a Pingle, especially for no good reason. I have considered fuel splashing at the top of the pickup tube but if that were the case it should happen more often and not at 80-100 miles, given I usually get 35+ mpg. The abilty to switch to reserve and back later is also confusing. I have a "Red-Eye" fuel line/disconnect which as far as I know performs as it should. As stated it usually happens at moderate cruising speeds and moderate throttle, not high fuel flow. Have not noticed but it may occur more on 80+ degree days. Have had the bike since 2000 and this has only happened in the past couple of years. Any one have any thoughts on what's going on or have a similar
problem?  Lets keep me on the road as a "Happy Valker".

[whitestroke]

I've heard of people having fuel issues with the quick disconnect.  All fuel lines including quick disconnect need to slope downward as the fuel system is gravity fed. Might want to shake the crap out of your tank also if it's never been done.

[Grumpy]

I had the same symptoms with my interstate, after 100 to 130 miles would act like running out of gas. switch to reserve and back and it would go away. I took the quick disconnect off, and never had it do it again.

[mmurffy03]

i removed my quick disconnect due to similar problems and all was normal afterwards it was connected to a pingle

[F6BANGER]

My 99 I/S has been doing that for years. Mine does it around 100/150 miles. Sometimes it does it every tank, sometimes not. ???
Like you, I turn the fuel selector to reserve and back and it fixes the problem. My vent hose isn't kinked either. I think its a very small hole in the diaphragm or a hole in the vacuum line.  When the tank is full, the pressure pushes the gas down. Then when the pressure isn't strong enough the vacuum takes over. Why it doesn't do it every time, I am clueless. One of these days I will fix it...

[mmurffy03]

never trust anything with a hole in its diaphragm

[sandy]

If your fuel line is stock, rebuild the diaphragm in the petcock. Get a cover set from HDL and follow the directions.

[Chiefy]

My Standard did that every tankful when I got it.  I put in a new OEM petcock, and it now does that only once in a great while.  I am told it is inherent with OEM petcocks.  Your diaphragm is dico'd so I don't know if that applies to you.  Stiil, information is a good thing.   You also said you have have quick disconnect.  I don't, but I've seen mentioned here time and again where something like what you're describing can happen if there is a low spot in the fuel line.

[Willow]

My Standard did that every tankful when I got it.  I put in a new OEM petcock, and it now does that only once in a great while.  I am told it is inherent with OEM petcocks.  ...

It's definitely not.

I've heard of people having fuel issues with the quick disconnect.  All fuel lines including quick disconnect need to slope downward as the fuel system is gravity fed.

Sometimes when the quick disconnect is installed a little extra fuel line results in a droop on the downward travel.  That droop easily results in exactly what has been described.

[Hoser]

I'm with Willow, seen it before.  Hoser 

[R J]

Make sure the disconnect is drooping down and not lower than the outlet hose.

Best suggestion there is to take it off.     If you take your tank off that a quick disconnect is needed, you need to keep your firkin fingers off the tank.

Gas doesn't like to flow uphill on a vacuum feed, and since the Valk does not have a fuel pump, it is not recommended.   Ya need to read the fine print on their website.      The last time I looked at it, like 3 or 4 years ago, in very small print, it stated something like need a fuel pump to work correctly.

Yes, I had one of them, fought it for 2 years and the 3rd winter it went bye bye and my problems also went bye bye, so I DO NOT suggest ya put one of them on.

[Oklahoma_Valk]

never trust anything with a hole in its diaphragm

+1

[fordmano]

Best suggestion there is to take it off.     

Gas doesn't like to flow uphill since the Valk does not have a fuel pumpneed a fuel pump to work correctly.

Yes it does have a fuel pump,,, if you install a belly tank that is. I really like having the Belly tank and fuel pump and inline fuel filter.  It just makes sense that these beasts should have had a pump from the factory The Goldwing has always had one.

Sorry R J just poking at ya, sorry 

[Chuck K. #5458]

OK, have had some time to think about and digest everyones thoughts on this problem. The only plausible answer in my case, as I see it may be the quick connect fitting. This does not however explain the mileage/timing of the problem, usually between 80 and 100 miles. Also gas or other liquids will seek the lowest level once flowing even with a sag/loop in the line as long as it has not been raised above it's original level when flow was started, think siphoning a tank. I'm not yet convinced the solution has been hit upon. I like the disconnect and would like to keep it unless I'm convinced it definately is the problem. Any more thoughts?

[Bone]

Seems to me it's about the pressure (weight) of the gas in the tank. After 80 to 100 miles you would have used up 3 gallons of gas. At 6 lbs. per gallon that is 18 lbs. less pressure on the gas leaving the tank.
Now turn it on reserve and you add 6 more lbs. of weight on the gas flow at the fuel line and it begins it's siphon action again.
My 6 lbs. per gallon is a guess I don't remember the true weight.

[Chuck K. #5458]

I like that thought BONE right up till I turn the petcock back to normal after I go 10+/- miles. After that it seems to run alright again. Have had some good ideas but I don't think quite there yet. More thoughts? Riding in FL this winter but MI in the summer. No discernible difference with that however.

[Bone]

I wondered about that also. We have had several complaints about the changes made in the fuel supply with filters and disconnects. Without doing a controlled test MAYBE starting the flow of gas again by opening the reserve keeps the siphon flowing.
Maybe

[97Valk_CT_Euless]

I think your theory is right about the weight of gas adding to the fuel pressure, but it's the height of the fuel, not the amount, that will add pressure. There's
Maybe 10" of fuel pressure with a full tank, measuring all
The way from the top of the fuel level to the
Needles.  Goes Down to maybe 6" near empty. Not a lot of pressure empty or full, but
As you say, more when full.

[Oklahoma_Valk]

Well it sounds like the guys have pinpointed the issue. Fuel starvation via the quick disconnect. After you make any changes/troubleshoot make sure to report back here how you fixed the issue!

it helps others in the future.

-Ride safe

[Chuck K. #5458]

You may not hear back from me on this. I like the ease of my disconnect and if I know that switching to reserve and back later will clear up the condition I may well live with it. Then again i may get the urge to remove the disconnect and see if it seems to stop the problem. I have many days/miles/rides to decide so........... If anyone does stumble upon the DEFINITIVE cure, please post so we all can remove one burden from our/my overloaded mind. Thank you, Thank you vey much!

[Willow]

You may not hear back from me on this. I like the ease of my disconnect ...

You may not have to remove the quick disconnect, but do consider checking to be certain you don't have any extra fuel line that could result in a slight sagging (maybe especially after it warms up).