Fuel problem???

[WoodyFL]

Posted this in the Tech Forum but hoping some of the locals can identify.


Took the Valk up to Daytona from Orlando today to get a new helmet. Ran smooth as silk as it usually does. Put her in the garage for about an hour and a half. Decided to go up to get some eats, got about 2 miles down the road and she starts chugging like the main tank was out of fuel. Come up to a red light and she quits. There were 4 bars on the gauge and the gauge has so far been accurate. Switch to reserve just to see what happens and she will not start. Pulled over up a ramp to the sidewalk, checked connections, opened the tank and heard some fuel sloshing, closed the lid, tried to start and just kept cranking, no pop. Checked all the connections again just to be sure, no kinked lines or disconnected lines. Tried to start about 3 minutes later and she fired right up. Switched back to the main tank and she ran fine back to the house. Getting nervous as I'm about ready to take her up to Chicago and back next week. Bought her back in January with 29,400 miles and I've put about 3,000 miles on since then and have not had any issues to date until today.
Any ideas?

Bob

[Grumpy]

Bad diaphragm in the petcock, or pinched vacuum hose or has a hole in it ??

[WoodyFL]

Going to try and take a longer ride tomorrow after work to see if it happens again. Could not find any visible signs of kinks or holes in vacuum lines. If it replicates tomorrow I'll have to look into the petcock possibility Grumpy.

Thanks.

Bob

[darksidemxer]

Id check for any signsof vapor lock. I have had bikes do it from the vent holes or hoses being clogged. The 3min wait to start makes me think thats a possability. Although u did pop the cap off....hmmm. couldnt hurt to check your vent lines etc. Found a wasp was clogging my klx250sf line once lol

[Thunderbolt]

When you opened the cap did you hear air rush in?  If so there may be a kink or obstruction in the vent line at the rear of the tank.  Have you had the tank off lately?  It is easy to kink the vent line when reinstalling.  Check the vacuum line on the rear of #6 cylinder intake and make sure it doesn't have a hole or crack in it near the intake.  If none of the above I would take the tank off and check the petcock for proper operation.  IE fuel flows when vacuum applied and will hold vacuum.

[Bronxboy]

What Grumpy said   If u do go out again and it quits all together she wont start again.

[Chrisj CMA]

If it is the petcock, it will do nothing but get worse and worse.  you might try getting on a higher speed limit road and see if it will run at 65 or 70.  If the petcock is starting to go bad it may run on city streets just fine and crap out 5 min after you try to run at highway speed.  That's because the fuel valve can no longer keep the carb bowles full at maximum demand

[WoodyFL]

After pondering on all of the feedback I received on this I decided to go with OEM petcock replacement due to time constraints. Had to order from Honda with overnight charges (OUCH!!) but I picked it up today at lunch, came home from work, removed the old petcock and put the new one in. Ran it in the garage at about 2500 rpm for about 10 min and all seemed well. No leaks, no cutting out..etc.
Bolted the tank back on and took a ride around town for a bit and ran up and down I-4 for a while.
She purred like a tiger!
Maybe it was my imagination, or just hoping, but she actually seemed to have more kick!
Anyway, the Valk is ready for the trip to Chicago. Now all I have to worry about is the weather on Sat up through GA, which is not looking too good right now. Gonna wait till Sat morning to make a decision whether to leave then or put off a day.

I would like to thank all of you who responded so quickly and gave advice!

Hopefully when I get back I can join ya'll for one of your Sat rides! 

Bob