fuel line

[dunk 1]

Hello - just a quick question to ask where people get their fuel line from, most suppliers of 7mm don't seem to say their line is ethanol resistant, am I to assume that most is these days or am I simply not looking hard enough - thanks - Duncan

[3potjohn]

Carrot Cycles : You can get green Ariete ethanol resistant tube if you wish, I got some black for another bike. Some are a tight push fit ( hot water) others have clips.Just be sure ti check your diameters. I have used them for a few years.
John

[dunk 1]

Thank you John - had a look and come up with the same issue - the 7mm is not available in many of the types and where it is they do not say it is ethanol resistant where they are quite pointed in saying that others are - if you get what I mean.
Am I correct in assuming that 7mm is the correct internal diameter - would 6 stretch?
Duncan

[harrymuffin]

Did they really use ethanol resistant rubber fuel hoses in the 20's, 30's, 40's 50's and 60's when you could top up your vehicles with ethanol added fuels such as National Benzole(?), and another but cannot remember the name off hand at the momentm, but I am sure someone will come up with the fuels name? They gave the engne a bit of a power boost and kept the combustion temperature in hand.
Have you tried ebay, I have managed to buy qite long lengths of the 6mm which is near enough to 1/4", no point in trying for 7mm as the petrol taps and carb inlet, are nearer 3/16".

[morini_tom]

I have never found a hose which looks like the original green hose which doesn't at least harden after a worryingly short period of use.

You need to know what your fuel hose is made out of and in my book, if it doesn't say then assume the worst. Any decent brand will have writing along its length which confirms the material spec.

Originality seekers may baulk at the thought of black rubber fuel hoses instead of clear green, but I would prefer my bike stayed fuel tight! I have heard of recent productions of the green fuel hose being much better, but the last lot of 'pukka green stuff' I bought from the fuel hose man at novegro Mostra Scambio still went hard in not much time.

I now always use fuel hose marked FPM/ECO with an aramid braid between the layers.

FPM (Viton more or less) has excellent resistance to fuel and ethanol.

If you can't get FPM then NBR (Nitrile) is ok but won't last so long if there is more than a few percent ethanol.

Last time I re-hosed my sport I used 7.3mm internal bore Cohine FPM/ECO hose. It's terribly expensive (£20 a metre or something) but then you don't need much and it lasts a long time without splitting or going hard. 7.3mm fits the dell'orto barbs and fuel taps fine, although I always also use a fuel hose spring clamp for added security.

I would never stretch too small fuel hose over a fitting- most hoses are laminated and if you stretch them you can split the layers which can result in fuel getting between the layers unseen- if you're lucky you'll spot a blister in the fuel line before it becomes a leaky mess.

It's also fair to say that I am very fussy about this- partly because on a Dart you can't see the fuel hoses or the beginnings of any drips so you have to be certain the fuel system is up to the job, and partly as having worked on the development of a number of ethanol fuelled engines I've seen what ethanol can do and the lengths manufacturers go to to make sure their fuel systems are compatible.

Also, for what it's worth, I am not against ethanol as a fuel at all. In combustion terms it does have its benefits. Like all things, understanding the limitations and making appropriate changes where required is the key thing. When leaded fuels were phased out many people got new valve seats etc. Now that ethanol is coming, the right thing to do is to update your fuel system accordingly, and understanding and using the correct spec of rubber is one aspect of that. Swapping the fibreglass fuel tank for an aluminium one on the dart was another change I made at great expense but because it was the right thing to do.

If in 10 years time I have the choice of running my motorcycles on green biofuels or not at all, then I'll be happy to put E85 in the tank (after various other updates of course)

[robint]

As a source for hoses go to your local industrial estate and find a supplier of hydraulic hoses who seem to stock everything hose and clip wise or if they don't they have a catalogue to hand which does.....if you have a choice go to the one with a motorbike outside.......

[AntietamClassicCycle]

I use this: https://www.mcmaster.com/5552K25 Although it says not to use it with ethanol fuels, it works fine, just needs to be changed when it turns brownish in color and shrinks slightly.

[Al Limite]

Dunk1, If you are still looking for Ethanol resistant fuel lines take a look at Codan SAE J30 R9. In 2015 I was on a similar quest and eventually bought the Codan product. It is not cheap but if memory serves me well it was about £5 a metre from an aircooled VW car website (I.D. for VW and MM similar). Mine was 6.3 mm I.D. and once warmed and pliable slipped in place.
Five years later running E5/E10 without issue.

[dunk 1]

Thank you - that also is available in 7.3 mm, would prefer the traditional thin line green look but longevity over appearance seems the better option.

[Vitesse]

Thank you - that also is available in 7.3 mm, would prefer the traditional thin line green look but longevity over appearance seems the better option.

I got mine for my Guzzi from Ducatipaddy. He has various sizes and fixings and seems to know about old Italian carbs and accessories.

[nickst4]

Funny old business; having to have the old green fuel pipe. To me, it looks as nasty as having lashings of red hermetite all over the engine casings, but maybe history-of-the-piece sticklers would go for that too?

For fuel pipe, I go for opaque black stuff without reinforcement because it is so much more pliable for motorcycle use, where space and angles are often restricted. It is generally sold as suitable for various makes of Japanese bike. So far as I know, it is compatible with ethanol-containing fuels but I always use Esso's best that still doesn't have that contaminant. Long may that stay so, especially for bikes with plastic tanks!

Nick

[Morinioz]

Excuse me for being a foreigner but does all the fuel over there contain ethanol?
I remember from my racing days that silicon hose was the only thing that wasn't effected by the alcohol but it's very soft
Graham

[3potjohn]

Ethanol is added to fuel thought I believe it may not be in certain counties and on certain brand fuels. I just assume it is. On occasion water is also found if the storage tanks are not clean.Fuel hose will inevitably develop embrittlement eventually, you just have to keep an eye on it.( ex SAAB EMS owner) In any case I change it about bi-annually.Well that is the plan.....Likewise it is good policy to clean out and check the tank from time to time. The side stand side is a favourite for corrosion. Still not as much trouble as on some bikes. Thinking of older injected motors.
John