i need carb help!!

[HooliganCycles]

so i just bought another xs650 this one is a 1977, not sure what model the carbs are but i do know the ones that are on the bike are the originals, the bike has not been messed with at all. so to make a long story longer i cleaned the carbs the bike fired right up and ran great, rode it across town and back with no problems, later that day while it was parked fuel started puking out the left carb, so i figured my float was stuck so i checked and it was working great so i lowered the float height just slightly, problem solved, the next day the right carb is doing the same thing, checked the previous ended up being a hole in my float, so i drained the float and soldered the whole up, now that problem is solved, my current problem is that now i go about a mile and the bike dies, wait a minute and it fires back up, and so on....so i am now thinking maybe the float height is to low and i am running out of fuel....does this sound likely??? in my experience with float heights normally the bikes wont die they will just be very limited....anyways any help or suggestions would be awesome....oh i also adjusted the timing and points and replaced both needle and seats. help please. thanks guys

 

[5twins]

Next time it dies, open the gas cap. If you hear a "whoosh" sound, your gas cap vent is plugged and a vacuum is forming in the tank stopping fuel flow. Float height for the '76-'77 carb set is 25mm. I have a set and they run fine at that setting.

 

[Ghetto]

I am going through the same thing and I am suspecting the tank vent as well..

 

[HooliganCycles]

Well it's worth a shot, I am gonna go hop on it now and just loosen the cap and see if the problem goes away, I will let u know shortly.

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[SCHMEEL]

I'm having these same "carb" problems also on my 77'. re-jetted runs great for a day or two then just doesn't want to take off like it should. sorry for thread jack but now i'm subscribed to the thread

and I took the cap off at work the other day and cleaned the vent hole, same problem persists

 

[5twins]

Well, if you have a plugged vent, it will only run for 10 or 15 minutes usually, then die, not for days. I plugged mine accidentally by strapping a tank bag on too tightly. I got a few miles from home before the bike died. And a plugged vent usually won't kill the motor like an on/off switch, it dies gradually like you were running out of fuel (which you are). Just like the bike behaves when you need to switch to Reserve.

 

[HooliganCycles]

5twins- good call that seemed to fix it, i dont know why i didnt think of that sooner. i just rode it about 30 miles or so which is way farther than i have been able to go so far....i should have caught the problem to begin with because when you take the cap off the PO had tank liner all over the bottom of the cap, i guess i didnt think about it because i had the tank propped up the other day (standing it up vertically) and fuel slowly dripped out from the cap so i figured the seal wasnt that good to begin with, but i peeled the liner of and poked a safety pin thru the vent hole and so far no more problem. thanks for the help that was getting very frusterating, i have hitch hiked more in the last two day than i care to do. thanks again.