Fuel line replacement on 81 gs650gl

[WilliamGLX81]

I replaced the fuel line on my used bike (hoping for my license next month) with some polyurethane tubing. It's rather stiff, and I left it a bit long.

It seemed like the nipple between carbs 2 and 3 was very very hard to reach.
1/4" tubing fit the petcock perfectly, but was impossible to get on the carb nipple.
I ended up moving from 1/4" to 3/8" tubing to get the tubing attached. Is that a proper size?
The 3/8" line seems fine on the carb nipple, but too big for the petcock. I've added an in-line fuel filter, and I stretched a short piece of 1/4" line onto the feed side of the filter to make a good connection to the petcock.

Is there some secret to replacing the fuel line? At the moment, it seems to be too long, and has folded itself, cutting off my fuel. I think that's due to the length, but ... argh!

Thanks for any advice,
William

 

[Steve]

The PROPER line is 7mm, available at your dealer or any of the online vendors that supply OEM parts.

As you found, 1/4" is too small. The next size up is 5/16", which is real close to 8mm.
It can be used, but will require a good clamp. 3/8" is way too big.

Adding a filter is not usually a good idea. Most filters are designed for pressurized systems in cars and will not work well with bikes.
If your line is too long, it WILL get kinked, blocking off fuel flow. Please remove the filter and install the proper length hose.
If you are worried about filtering your fuel, remove the source of contamination by cleaning your fuel tank, then ensure
that your filter is intact over the petcock intake.

.

 

[Mpenner]

Inline fuel filters are a staple of every bike I own. Don't go to local car parts store and pick one up because it will but be right. Go to local bike shop or small engine shop and get one. They are usually under 2 bucks, and they will keep your carbs clean!

 

[duaneage]

To insert on the fuel tee lube the end with silicone spray and insert a dowel rod through the line. This makes it rigid enough to shove onto the fuel T.

 

[Turtleface]

I replaced the fuel line on my used bike (hoping for my license next month) with some polyurethane tubing. It's rather stiff, and I left it a bit long.

It seemed like the nipple between carbs 2 and 3 was very very hard to reach.
1/4" tubing fit the petcock perfectly, but was impossible to get on the carb nipple.
I ended up moving from 1/4" to 3/8" tubing to get the tubing attached. Is that a proper size?
The 3/8" line seems fine on the carb nipple, but too big for the petcock. I've added an in-line fuel filter, and I stretched a short piece of 1/4" line onto the feed side of the filter to make a good connection to the petcock.

Is there some secret to replacing the fuel line? At the moment, it seems to be too long, and has folded itself, cutting off my fuel. I think that's due to the length, but ... argh!

Thanks for any advice,
William

I just got a package of OE fuel line in the mail yesterday. You get enough line to do a bunch of bikes. I also have to ship off a bunch of parts tomorrow. As such, I wouldn't mind sending a bit of fuel line your way. PM your address, and it'll be on it's way.

You'll want to use just enough to reach from the nipple on the carbs to the nipple on the fuel petcock. Make sure any necessary bends are nice and big, so you don't pinch the fuel line.

On my 1100EZ, I pulled the tank off completely to get the new fuel line on the carbs. Then I put the tank back on and I prop the back of the tank up with a 2X2 block of wood to give myself some working room for my hands.

Fuel filters aren't really necessary, if your tank's clean and you've cleaned your carbs properly. Keep the tank full, and you won't have to worry about rust, or you can seal it with various kits. An inline filter introduces two new places a fuel leak can occur, and seem to be problematic for some.

 

[Turtleface]

To insert on the fuel tee lube the end with silicone spray and insert a dowel rod through the line. This makes it rigid enough to shove onto the fuel T.

Now you tell me! Oh well, that trick will come in handy later. I assume the silicone will just be harmlessly drawn through the carbs and into the combustion chamber to be burned off during start-up?

 

[duaneage]

Now you tell me! Oh well, that trick will come in handy later. I assume the silicone will just be harmlessly drawn through the carbs and into the combustion chamber to be burned off during start-up?

Beats taking the carbs off when you forget to add the line after a rebuild. A little bit of silicone spray won't stick around for long once gas goes in.

Make the line much longer than required, it can always be cut later. It's harder to make them longer.

If you use a filter make it a small one for lawn tractors. This is a gravity feed system and large filters build up vapor pressure. Fuel pumps overcome vapor pressure just fine but gravity feed has trouble. Basically the vapor will cut off fuel flow in hot weather, especially up inside the engine area at a red light.

If the tank and petcock are nice and clean a filter isn't really needed.

 

[WilliamGLX81]

Woah! Excellent!

Okay, the fuel filter I'm using is one from a local bike shop. These were the only two sizes of fuel line they seemed to have, so I'd love to get a piece PIF-ed to me. (Pay If Forward). I'll pm you in a second.

I'm not too sure about the condition of the petcock, but I know the carbs were cleaned. The petcock is stiff and I plan to rebuild it and replace the filter when I repair the fuel level sender...... But first I plan to get myself riding and off the county bus system. It'll save me some 10 hours a week riding instead of waiting and walking. Nothing like the freedom you get from personal transportation!

William