I need the fuel hoses for a K1 model onwards. Just the ON and RES ones are critical but if you've got the PRI one too that'd be great. Let me know how much you guys are asking, the ones I have are all worn and cracked.

Ace hardware, Advance Auto, {insert name of any dealership here}, Wal-Mart, ebay, Amazon....
You can get fuel line pretty much anywhere.
The general consensus, based on my reading of the same topic, is to avoid the reinforced automotive line, since it's too thick to fit on the tank nozzles.
Also, the cheap clear vinyl stuff may or may not be good long-term, since it's not technically 'fuel-rated', though plenty of people use it with no issues.
Tygon tubing is about the "best", but only lasts a few years and is expensive.

Oh okay I'll look into that. I checked out a few auto stores before but they only carry imperial sizes so I guess 5/16th is the best fitting. I wonder if both the ON and RES line will fit without interference though because of how close they are on the tank petcock.

Try searching here for "fuel line". There are TONS of replies.
In short, the OEM size is 7mm, which is pretty much unavailable in the US unless you order it from overseas.
You can use either 5/16 or 1/4. 5/6 will be a bit lose and will require hose clamps, 1/4 will be a bit tight and may be tough to get on initially, but will most likely not require clamps.
You cannot use the thicker automotive reinforced fuel line, it will not fit on the fuel tank nozzles.

I have to slightly disagree, ive used the automotive stuff . ONCE. Never again . A major fight on a 97 E. Anyhoo this work?http://www.ebay.com/itm/Porsche-VW-3-Feet-7mm-Cloth-Braided-German-Fuel-Gas-Diesel-Hose-Line-Volkswagen-/201185508765?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ed7973d9d&vxp=mtr

I agree that you should disagree with me. 
I'm only repeating what I've read here, in an effort to save the OP some searching time, but personal experience trumps "internet wisdom" any day. 
I saw that eBay link when I was searching for my fuel line. Have you used that stuff? It looks like it might be too thick with the braided cloth covering, causing the same issue as with the reinforce automotive tubing.
What are you running on your GS?

I was recalling when i resurrected frankenbike in 03. Was a VERY tight fit. Auto line from advance auto parts. Tbh this stuff seems narrow er than that. If i could find a scrap piece i could measure. Will see what else i can locate. I know most parts houses carry the tygon tubing its not really THAT expensive

Where the heck do you like where local stores carry Tygon?!
I ask for that stuff here, I get dumb looks. Even asking for non-reinforced fuel line brings out the blank stares. lol

Try laboratory or pet supply stores. Tygon is used for gases.

Quote from: Elmojo on December 24, 2014, 07:46:09 PM
Where the heck do you like where local stores carry Tygon?!
I ask for that stuff here, I get dumb looks. Even asking for non-reinforced fuel line brings out the blank stares. lol

here in tn napa has it. Would buy it for goped repairs, looked like there was some also that would fit a gs . they had as i recall 8 different sizes on hand

NAPA? Really?
I never go in there, maybe I should...

If they dont have it, they can get it in next day. And sell you only what you want

Good to hear, I'll check with them this week, thanks.

Glad to be of assistance

Have you tried your local motorbike shop?
I dunno about elsewhere, but in Oz, bike shops carry the right stuff off the roll, just buy it by the foot, a couple of bucks.
It is NARROW WALLED - it needs to be. It fits. It lasts. BTW watch out for the nozzles into the tank tap/outlet, they dislodge a bit too easily if you pull at them too hard. Use a heat gun or hot water to soften the hose if it's hardened.

Oh, if only I lived somewhere that had actual "shops", not just $tealerships and back yard Bubbas. 
My choices here are:
1) buy parts from a dealer.
2) order online

Buying from a dealer isn't too bad, since I live about 20 mins from Ron Ayers.
I can order online or on the phone, and pick them up to save shipping.
Maybe they can get Tygon, I'll ask...