Intermittent throttle loss? Where to start...

[disco51]

Dirty petcock or fuel filter it was...
After cleaning out the tanks, I decided to do the petcock.  Lots of crap in there.  Also changed out my inline filter, which had more debris than I noticed.  Problem is now fixed.  No hesitation.  I also got a smoother working petcock in the process.  Thinking of ordering the newer screen for it as well with the washer installed.
I did take apart the carbs and did the "field fix" or something like that that snowbum described.  I sprayed some carb cleaner and cleaned out the main jet.  Also inspected the diaphragms and no tears or holes that I could see.
Again, appreciate all of the help.  Hopefully will get some riding in now before the next problem surfaces...
Thinking of trying my first oil change next.

[steve hawkins]

Well done for sorting it yourself.

And thanks for letting us know our advice has been useful.

Cheers

Rev. Light

[raypond]

Just to finish off this thread:

100ml per minute is the required amount of fuel. I think this this comes from one of the gurus' websites but it can be checked with some simple arithmetic.

If you travel 100km in one hour you will (in conveniently round figures) use 6 litres of fuel. That's 6000ml in 60 minutes = 100ml per minute.

If less than that is getting to the carbies you will, in effect, run out of fuel.

[flybot]

Hmmm.
100ml = .42 cups. However, looking at snowbums stuff, he shows 1.5-2 cups/min.

Snowbum quote:
5.  Questions often arise as to whether or not the screen, petcock, lines, filter(s), etc., are flowing enough fuel.   This is easy to actually calculate, if you figure the worst case, such as 20 mpg at wide-open throttle.      But, here is a guideline of mine, that is perfectly adequate, and you don't have to play with mathematics:    If you have a small displacement airhead, such as a R65, you need a cupful of fuel flowing from EACH carburetor, separately measured, bowl removed, common household 2 cup measurer underneath carburetor, in one minute or less.   For the larger displacement airheads, a cup and a half or more is OK.      NOTE:  fuel flow problems such as stumbling after a bit of cruising....can be caused by fuel cap venting problems, not just clogged fuel screens and filters, etc.

When I checked mine I filled up 2 cups in about 20 seconds and called it good. I think less than a half cup in a minute seems very low IMO.

[Air4Life]

f you travel 100km in one hour you will (in conveniently round figures) use 6 litres of fuel. That's 6000ml in 60 minutes = 100ml per minute.

if you figure the worst case, such as 20 mpg at wide-open throttle.

Seems to me you guys both shared good information, assuming the math was correct.  One took the best case scenario and the other the worst.  Though I must say, I like to take the worst case scenario as it would reassure me that their's enough left over should I want to pour on the coals [smiley=whip.gif].