air bubbles in fuel line

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TikiMan
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air bubbles in fuel line

Post by TikiMan » Tue May 22, 2012 12:21 pm

Hello,
Its a afo5e stock motor with a 90 jet. The other day it started to slow down while at half throttle and it just didnt have any top end after that. I noticed when it revs high there is a huge amount of air flowing up the gas line. What would cause that and how do I fix it.
88 SA 50- Af16e swap
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Bear45-70
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Re: air bubbles in fuel line

Post by Bear45-70 » Tue May 22, 2012 1:25 pm

"Huge amount of air" One big bubble or a lot of little ones?
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TikiMan
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Re: air bubbles in fuel line

Post by TikiMan » Tue May 22, 2012 2:26 pm

one Big bubble at first and then its streams of little bubbles until it goes to half full. it doesnt fill back up until I stop and crank it a couple of times.
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Bear45-70
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Re: air bubbles in fuel line

Post by Bear45-70 » Tue May 22, 2012 2:38 pm

You definitely have a a problem. It could be from the tank or the petcock causing this.

Try running without the gas cap down clear tight and see if that helps.
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bakaracer
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Re: air bubbles in fuel line

Post by bakaracer » Tue May 22, 2012 3:55 pm

if your fuel line at some point goes up just a little before the carb, that will cause bubbles and a slow fuel flow
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TikiMan
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Re: air bubbles in fuel line

Post by TikiMan » Tue May 22, 2012 10:58 pm

Okay I made sure the hose is perfect length and now its just a stream of little air bubbles. Suggestions for next thing to investigate.
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Re: air bubbles in fuel line

Post by bakaracer » Tue May 22, 2012 11:45 pm

TikiMan wrote:Okay I made sure the hose is perfect length and now its just a stream of little air bubbles. Suggestions for next thing to investigate.
so the hose had a section that was going in a up hill direction?
Nothing like getting stroked!
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r

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Bear45-70
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Re: air bubbles in fuel line

Post by Bear45-70 » Tue May 22, 2012 11:50 pm

TikiMan wrote:Okay I made sure the hose is perfect length and now its just a stream of little air bubbles. Suggestions for next thing to investigate.
From which direction are the bubbles coming from, the top or the bottom?
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'83 Aero 80 X 3
'84 Aero 80 X 3

'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree

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