That was weird..need an objective view

[Lucky]

Frustrated that i couldn't make Britjam today, i figured i could at least take the bike to the supermarket to pick up dinner. (shish-ka-bob & garlic crabs on the grill) on the way back home i was flogging the bike pretty good & playing with some Harleys.  I hit redline pretty well a couple of times, & then it started bogging like crazy over 4K, then stalled out.

i coasted into a parking lot thinking 'great seafood in the saddlebags..'  i tried to start it & the starter sounded a bit weak (seal is good) i killed the lights & it cranked better. i got a jump start & it kicked right over, so i'm thinking charging system.  i have a analog meter in the dash, & it reads 2 v low, this i know.  the readings were as they allways are, & i haven't yet put a digital meter on it.

something else.  in the parking lot i found gey oil/water mixture dripping from the seal (outside) on the starter, but the oil in the crancase window looks nice.  i'm thinking it might have been water from the last time i washed the bike  somehow mixing with a slow leak i may have at the starter seal housing.. but just seeing it makes me nervious.

i don't know if it wanted to bog on the way home, i baby'd it.  once back home it started right up, & started up fine later tonight as well.

so i'm thinking charging, but i seem to remember it doing this once before after running the tach way up there... carbs are clean, fuel system is working, i did a valve adjustment last year & it ran better than ever.. also new plugs wires & caps, rev limiter is disconnected as well as side stand relay, etc.

i'll run the electrex tests & double check fuel, anyone think of anything i havent considered? the bogging after redlineing it is weird, unless the fuel pump's dying & can't keep up...

thanks, --Lucky

[mark_m]

Random newbie  thought: Could it be the battery? I had a bike that had a bum battery and would jump start but would run very rough and die randomly until I replaced the battery and that completely fixed it.

Mark.

[Lucky]

i didn't check the water in the battery...it'd be nice if it was something simple i overlooked, it often is which is why i asked...

[Walt_M.]

Any chance your fuel filter is plugged up?

[bmeyer6472]

My guess would be a fuel starvation problem - maybe the above suggestion that the filter is clogged - I had a hot rod that did exactly the same thing, ran fine until you tried to use the power, then big bog. Good Luck! :-\

[Lucky]

good suggestions. i had the petcock apart last week (like you didn't know that, right) and found the return tube missing which allowed crud back into the carbs.  now i pulled the tops & they had a tiny bit of sediment which i blew out the drains, i guess i'll pull the carbs & dip 'em when i get back from vacation, as well as inspecting the fuel pump, changing the filter  & checking the charging system & battery..

wouldn't be at all surprised if it was a combo problem

[Kevin]

Lucky  you are running a inline fuel filter as I remember. You could be running out of gas. The filter is another restriction. I've seen this happen on flattrack bikes.Kevin C. 

[Coil Coyle]

weird, unless the fuel pump's dying & can't keep up... :'(

If all the filters are OK, is the vacuum line to the pump intact?

coil

[Ken Williams]

Especially because this problem occurred after you replaced the petcock return tube, my guess is your fuel pump isn?t getting sufficient fuel to the carburetors.  With the return tube missing, the carburetors were being filled by gravity, via the return line and by the fuel pump.  Now that you replaced the return tube, fuel is supplied exclusively by the pump. 

[Lucky]

Yea, all excellent possabilities.  i was thinking it is (was?) charging because I brought it to Ed's for my vacation (have i mentioned that i don't trust my neighbors?) & it kept dying. i finally had to call Ed to come pick me up with his truck (how embarrasing).  BUT everytime i stopped, i jump started it & it ran great for a while untill it died again.  i'm now thinking it was a coincidence & that the carbs would fill while it was sitting.

while fuel pump is a possability anyway, i don't think it's from the missing return tube because the fuel would have to fill the bowl & return thru the inlet needles to get to the fuel pump, & of course it would spill out the overflows first....

I have to call Ed & get the bike back here & i'll let you know what I find.

--Lucky

[Coil Coyle]

Lucky,
         If the return line to the tank plugged and the needle and floats held the pressure of the pump then eventually the gasoline in the pump would get near boiling temp (for gasoline) and the pump would vapor lock.

        ( Vapor Lock: as the diaphram pulls to suck in fuel, the liquid in the pump chamber boils, then when the diaphram pushes to pump the liquid goes back to liquid. Pull a bubble open / push a bubble closed, no pumping )

coil

[Ken Williams]

With the return line missing you do not need a functional fuel pump to supply the carburetors with fuel.  Now that you replaced the return line a functional pump is required.  Your fuel pump has most likely been unable to supply adequate fuel for some time previous to your installation of the return line.   

[Lucky]

The return LINE was not missing the tube was. Also the petcock was not plugged, just had some dirt in there from the tank.
i gotta get it home & look it over...

[Ken Williams]

You experienced symptoms that can be caused by insufficient fuel delivery.  As result, it is reasonable to suspect that the cause of your symptoms is insufficient fuel delivery. 

You experienced these symptoms a short time after reinstalling the fuel return tube/line protruding from the top of the petcock.  This additional information leads to greater suspicion that the cause of your symptoms is insufficient fuel delivery.  My earlier posts explain the reasoning for this assertion.

[Lucky]

Ok, i see wat your saying...

[EH]

I think it is a severe case of operator error.

[Lucky]

Very well could be, lol  see ya Sunday.

[dminor]

Lucky,
I had a similar problem after I put the carbs back in the bike, after much searching it turned out to be that the inline filter had cracked. It really messes up the regulator if there is an air leak. Just a thought.
Don

[Lucky]

got the bike home today (thanks Ed!) pulled the carbs.  took the fuel pump apart first & it looked fine. i flipped a diaphram over because it was a little streched in one direction more than another (the one towards the vacuume source)

Found the fuel filter Clogged.. that's one problem... replaced the brass tube i was using as a substitute  for my missing return tube with one Walt sent me (thanks Walt)

heard a slight hissing from the cap on the tank after it sat partially in the sun, i'll have to check out the cap vent next.

found a small leak in the already resealed YICS. i resealed it with RTV blue because it was all i could find.  i expect it not to last too long.  (how did you guys do those copper YICS tubes again?)

the rest of the carbs looked good, pulled all the jets, nice & clean, the bowls too, so the fuel filter did it's job.

I still have to double check the charging system for piece of mind, & check the cap. if the relief valve in the cap is messed up, i may just repace it with a piece of palstic with a pinhole in it...

[Lucky]

Took the fuel cap apart today, other than a light coating of corrosion dust all looked good, the ball was clean, & the tiny little filter looked ok too.

short 20 min ride & the bike ran great. i need some good HOT weather to see how it does then (to duplicate the conditions)

still have to test the charging system

--Lucky