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How to Make a Fuel Supply Line - for External Pump


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It seems that the braided steel covered, 12mm fuel line that goes from the petcock to the external fuel pump is not available from dealers. I was surprised at how difficult it was to have one made - and even went to a local speed shop - where I almost succeeded. But then the special clamps wouldn't work... long story...


So here's what finally worked:

  • 12mm fuel line. This stuff is hard to find in the US. 1/2-inch is the closest, at 12.7mm, and the stuff at the hot rod shop was 11.something... I found a 10-foot roll of true 12mm line on Amazon.
  • 3/4 inch hot rod sleeve by Heatshield Products (to fit the 20mm outside diameter of the 12mm fuel line - this is rated up to some very high temperature that I hope my motorcycle will never see.
  • 1 1/2 inch rubber heat shrink ends by Heatshield Products (they have a 3:1 shrink ratio). At first, these ends seemed like they were way too big, but they shrunk right down with the heat gun and made a nice, thick protective end.

The rubber ends are much thicker, and I hope more durable, than the ends on the original hose. BTW, I used the big socket to roll the ends of the heat shrink flat where they wrap around the cut end of the sleeve.


I had to buy 10 feet of the line and the sleeve. The heat shrink ends came in an 8-pack, which will do 4 lines. 


I installed one of these on my Greenie and have been riding it for a while now. The line on the Greenie had rotted on the inside, and rubber debris clogged the fuel pump inlet, causing unhappiness. I just made this line for my Scura.


If I buy some more ends, I can make at least 8 more lines. I'd be willing to sell them for $27.00 including US shipping. That will cover my costs and net me two free fuel lines for my effort.  Send me a PM if you want one. 



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Man, I just missed out on this. I was in need of a new one about a month ago. Found one on ebay for, I think, around $25, but with international shipping, it totaled around $60!


Sent from my SAMSUNG-SM-G930A using Tapatalk

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Scud...this is perfect timing...I just discovered a fuel leak yesterday after a weekend ride on the metal downspout (LHS right above the throttle body, since I'll have to pull the tank and review all the lines under there, I'll take one of these as well!  I haven't had the tank off yet, so I don't know if my 2002 has an internal or external pump yet.



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If your tank has a raised rubber tank pad (or carbon fiber in the case of Scuras) then the bike has an external fuel pump. If your fuel door is flush with the top surface of the tank, the bike has an internal fuel pump. Up to 2002 all bikes had external pumps. 2003 was the transition - the Sports had externals and the LeMans had internals. I believe all 2004s have internal pumps.

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Here's my Scura, wearing her latest dark-fashion accessory.  :ninja:




The 15 year old hose was still OK, but definitely harder and less flexible than the new hose. If you have smallish hands, you can replace the hose by just propping up the tank, not totally removing it. 


LowRyter's is on the way and I have a couple more I can ship immediately. I just ordered some more of the heat shrink ends so I can use the balance of the fuel line and heat shield. I can make 1, maybe 2 more than I originally thought, so if you all buy these, there will some money leftover for Jaap (forum donation).



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Makes me want to sell my bike and buy an earlier one so I can have one of those lines! :food:


Very funny.  Most people would consider the internal pump to be an upgrade.


The sleeves and heat-shrink ends are available in smaller sizes. I don't think it would cost much to put heat-shield on all the high-pressure lines to the throttle bodies. If I had known about these when I replaced all those 8mm lines I would have used it.

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I received the extra heat-shrink ends, so I made the rest of the lines, installed one on the champagne LeMans project, and have three more available for whoever else wants them.



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According to the package tracker, the new Scud Fuel Line should be delivered tomorrow and installed on SCUZZI shortly thereafter! 


The bike is all disassembled and waiting for the new fuel line, plus a couple of new O-rings from Harpers going in as well.  Good thing is that all other lines, cables, connectors  look like they are in great shape, everything snug and tight, and I even found a small missing hex screw for the left hand throttle body where the cable comes in wedged into a small nook.  That had been missing I think since I bought the bike, so quite happy it has survived the miles ridden to date snugly and comfortably wedged into a tight spot waiting to be discovered and put back in its proper place.  


Thinking I might want to replace the fuel filter while I'm at it since the tank is off anyway...then time to rack up some miles as we have the most beautiful weather ahead of us at the moment.

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