bubbling gas...

drhofferber · #1 06-24-2009, 08:11 PM

one of my bikes which has the 50cc in it has a problem...in the morning when i go to work it runs great, but in the afternoon when i come home it gags alot...i noticed that my gas is bubbling or boiling...i was using a ngk 5 and today i changed to a 7...any suggestions...thank you...Dennis

**Norman** · #2 06-26-2009, 03:18 PM

Is your bike sitting in the sun and getting the gas tank hot? The bubbling sounds like the fuel is getting hot and the light ends are boiling off, changing spark plugs will not stop a fuel problem.
You might try a different brand of gas. Keep your bike out of the sun. One more thing make sure your gas cap is venting, I haven't ran across one that doesn't yet, most will leak fuel out of the cap.
If you are using gas with the alcohol in it you might need to see if you can get gas with out the alcohol premium gas should not contain the alcohol but in these days and times its going to be harder and harder to find good fuel that had no alcohol.
Norman

drhofferber · #3 06-26-2009, 05:30 PM

Quote:

Originally Posted by Norman

Is your bike sitting in the sun and getting the gas tank hot? The bubbling sounds like the fuel is getting hot and the light ends are boiling off, changing spark plugs will not stop a fuel problem.
You might try a different brand of gas. Keep your bike out of the sun. One more thing make sure your gas cap is venting, I haven't ran across one that doesn't yet, most will leak fuel out of the cap.
If you are using gas with the alcohol in it you might need to see if you can get gas with out the alcohol premium gas should not contain the alcohol but in these days and times its going to be harder and harder to find good fuel that had no alcohol.
Norman

its not in the sun...thanks for responding Norman...i just finished changing the intake...i had a real short one and i think it was to close to the engine....this one is alot longer and straight...the float is square...i'm letting everything dry...tomorrow take it for a ride...the gas i use come out of the same can as 80cc uses...i use shell gas...i did do some resuch on oils red line seems to have the highest boiling point...i use amisol saber...never had this problem...thanks again ...i'll keep you posted...Dennis

**Norman** · #4 06-26-2009, 08:43 PM

I make and use a real short intake on a couple of my bikes and have not had the problem your having I live in the panhandle of texas and the days are screaming hot here not as hot a AZ. but very warm.

Cabinfever1977 · #5 06-27-2009, 08:06 PM

i dont think the gas was boiling,i thing you had airbubbles going back up the line.

drhofferber · #6 06-27-2009, 09:54 PM

Quote:

Originally Posted by Cabinfever1977

i dont think the gas was boiling,i thing you had airbubbles going back up the line.

what causes that?...i changed things around...i'll see in the morning...thank you...Dennis

drhofferber · #7 06-28-2009, 06:57 PM

Quote:

Originally Posted by drhofferber

what causes that?...i changed things around...i'll see in the morning...thank you...Dennis

well went for a ride this morning...put my deul exhaust on, cleaned up the long straight intake, changed the needle to the third notch....and it runs beautiful...no bubbles...intake stays fairly cool...deul exhaust sounds great...thanks for the help...Dennis