Gas tank cap vent

[Larry Zoia]

Gentlemens,

   Could someone enlighten me as to a procedure to check whether or not the 
gas tank cap vent is patent?

    I suspected a venting issue, so of course I shot some
WD-40 into the holes and blew them out with compressed air.  When my problem 
didn't resolve, I
(belatedly) looked in the manual.  It didn't tell me how
to check the venting.  It DID tell me not to use compressed air.

    During long periods of sustained high speeds (80-90 mph from Michigan to 
NJ this weekend) I noticed symptoms of fuel starvation which were 
ameliorated
somewhat by running with the petcock in the Prime position.

    Coming out of a gas stop, the bike, warm, runs great for about 20 
minutes at 85 mph or so, and then the starvation symptoms begin.  Same thing 
when I stop to pay a toll with the petcock in the Prime position.  I tried 
to look at the glass filter on the fly to check the amount of gas therein, 
but that manuever seems to result in a soft left turn and horns being 
honked.

   Sooo...my plan is to check the flow through the inline
filter (glass) to make sure the filter isn't the issue, then
remove and inspect the petcock for....well, whatever I
might find, and then back to square one with the venting.

   I do have a recently installed Stage III jet kit, but my
mileage has been around 44 mpg for aggressive highway (turnpike) riding.

  I remember hearing what I interpreted as air being sucked through the cap 
vent after idling the bike in the
garage for a few minutes, and this is what prompted me
to blow out the holes.

   Thanks in advance for any responses.


Larry in Michigan