Decent petrol pipe

  • Thread starter Thread starter John lord
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CLEMTOG said:
I bought some (allegedly) Cavis hose from a classic Fiat dealer, not very dear for a 25 metre drum, but in storage it has turned blue, when it was green to start with, and that is inside a cool dark cupboard, I have also noticed with most of the see through fuel hose, that it functions (mostly) very well all the time it is in use and has petrol in it, but if it is "dry" for more than about 3 or 4 days it goes rock hard and can even snap when bending it to refit.
CLEM

Things go rock hard with see through undies as well Clem.

Paul
 
sideshow said:
Does anyone use Ariete, from Italy ?

The green Ariete pipe indeed goes hard, the purple version is much more durable with its 2 layers. Over time it does lose its ugly colour and even becomes greenish.

Marnix
 
The problem with plastic hoses is that they all rely on plasticizer molecules "lubricating" the cross-linked long chain hydrocarbon molecules so that they actually slide over/past one another. And the plasticizers dissolve fairly well in hydrocarbon solutions (petrol is mostly octane, although God knows what else is in there) and get carried away quite quickly. So while polymer chemists could make a clearish plastic that could be formed into tubing and would stay flexible with petrol running through the tubes (and they actually do) it's meant for very specialised markets and is hellishly expensive. Typically it's not available for distribution outside target markets like industry or scientific research.
Rubber, on the other hand, can be formulated without plasticizers or with water-soluble plasticizer-like molecules, which don't dissolve in hydrocarbons (petrol). So it's not at all unusual to have original rubber fuel lines on pre-war vintage cars and motorcycles. The perishing of old rubber lines is usually due more to exposure to air than to whatever fluid flows through them. There's millions of vehicles on the road using 40-year-old pressurised brake hoses, and they're still safe. Sort of. Well, really should be replaced.

Ken
 
A few posts up is the link for what I used for a low-pressure brake line and I expect it would work for fuel. But at probably $200 to suit a Laverda its bloody expensive. Feels really nice though.
 
My RGS came with the standard green fuel hoses, thought nothing of it until about a year into ownership I had the tank off and thought it might be a good idea to clean the carby fuel filters. Took the whole assembly off; fuel rail, hoses and banjos. Was pretty shocked to find the short lengths between the rail and carbies were rock hard and had started to crack. Replaced with proper fuel lines and Jubilee clamps.
These days, if any company put out a product with fuel lines that deteriorated when fuel was added would find themselves hit with a global recall!
 
I use this stuff, it's blue when installed and turns into a nice green color over time. Stays soft and flexible, seems to last forever.
https://www.denniskirk.com/parts-unlimited/5-16-in-i-d-blue-polyurethane-fuel-lines-0706-0112.p185007.prd/185007.sku

HTH
Gerald
 
Gerald said:
I use this stuff, it's blue when installed and turns into a nice green color over time. Stays soft and flexible, seems to last forever.
https://www.denniskirk.com/parts-unlimited/5-16-in-i-d-blue-polyurethane-fuel-lines-0706-0112.p185007.prd/185007.sku

HTH
Gerald

Sounds it would exactly behave like the one I got last summer from OCT. Picture shows the same hose before and after the trip to Breganze:
49858338752_a903bdc9d5_c.jpg


It hasn't turned rock hard yet though and I can live with the colour change ...
8)
 
Dellortoman said:
Great minds think alike Gerald. I use the same 5/16" light blue polyurethane as you. I also made the same comment about it turning green  :D  (see reply #14)

Mea Culpa, Cam :D
 
That Neoprene CRAP fuel line will harden and crack and set your bike on fire within a year. Use Automotive Black Rubberized Fuel lines (Pipes) designed for Gasoline.

"Fuel Lines" NOT "Petrol Pipe" - What an expression ;o)

If running Hi-Pressure Fuel Injection, I recommend Braided Hydraulic Hose.

Braided Hydraulic Hose works great as a Manifold Crossover between intakes - It don't collapse.
 
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