Finally the proper fuel lines

baz

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I keep forgetting how long it’s been since I rebuilt the bike. It’s getting time to replacing a lot of things.
A mate has got only 14 months out of a pair of these inlet rubbers before they split
He phoned the shop and they told him "nobody else has had a problem with them"
I guess it's man made rubber that just doesn't last?
I have been told that putting footrest rubbers in a freezer bag with "waxoyl" stops them from splitting/perishing but I've not tried it myself
 
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I find most modern rubber items are crap now, at one time you could wear out a Trident motor and the footrest rubbers were still perfect ! :)
 
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A mate has got only 14 months out of a pair of these inlet rubbers before they split
He phoned the shop and they told him "nobody else has had a problem with them"
I guess it's man made rubber that just doesn't last?
I have been told that putting footrest rubbers in a freezer bag with "waxoyl" stops them from splitting/perishing but I've not tried it myself
Considering it’s been more like 10 years I don’t think it’s bad. It depends a lot if the rubber see a lot of sun and ozone. Two things that speed the determination. As for splitting it’s common for people to use things like screwdrivers to install those rubbers.
 
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I made mine using a hydraulic crimping machine and progressively turning and crimping to avoid having ridges on the ferrules.
 
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"I think the reason that they switched the fuel line to be moved to behind the Amal's was due to the possible blowout of the head gasket..."

Well, maybe but I think they did it simply because it was cheaper to produce. ;)
There was a service bulletin about replacing the old crossover type fuel lines. It was changed for safety reasons. I have seen flames coming out from a blown head gasket (not a Norton) and it was scary.
I like being able to see the fuel, but the stainless lines do look good.
 

speirmoor

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Have had the same set for a few years now and they have become yellow and stiff. Still function perfectly tho
 

L.A.B.

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Mine is completely brittled. I will go with AN fittings and quality hose. I will be starting with this from the tank on each side and move my way downwardshttps://www.ebay.com/itm/183253934543
That's a pipe connector.
The normal fitting is a nut and spigot.
 

Kjell

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That's a pipe connector.
The normal fitting is a nut and spigot.
Yes it is indeed. It is my understanding that the threads is 1/4 " BSP on both sides of the petcock. From there I will be using 1/4 Bsp to AN 6 adapter

 

L.A.B.

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It is my understanding that the threads is 1/4 " BSP on both sides of the petcock. From there I will be using 1/4 Bsp to AN 6
Seems like a lot of unnecessary complication.
Sorry, but I don't see the point.
 

Kjell

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Not very complicated in my opinion .AN hoses and connections are used within the drag racing industry all over the world.
When I saw the original fuel lines on my commando I have to admit I was amazed. Not even a hose clamp on the tee connections.
I guess we all spend our money were we feel its worth-
 
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Not very complicated in my opinion .AN hoses and connections are used within the drag racing industry all over the world.
When I saw the original fuel lines on my commando I have to admit I was amazed. Not even a hose clamp on the tee connections.
I guess we all spend our money were we feel its worth-
It’s just gravity fed so no pressure on the joints.
 

HRD

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I found the earlier type with plastic three way connectors to be very prone to leaking and deterioration with modern fuels. The whole line goes yellow, hard and brittle.
On earlier models the 3 way connectors were metal ( brass and plated ) and yes the lines went yellow and hardened but not so it became brittle .The fuel was not like today's .
 

Ron L

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On earlier models the 3 way connectors were metal ( brass and plated ) and yes the lines went yellow and hardened but not so it became brittle .The fuel was not like today's .
The lines go brittle because gasoline leaches the plasticizer out of the PVC tubing. Modern tubing designed for gas and oil like Tygon F-4040-A should be a better choice. The downside is the translucent yellow color and it is somewhat less flexible than regular PVC. There is also a clear version from another company (Excelon) that is supposed to be fuel resistant. I have made a set of lines from the latter, but it has only been holding fuel for about 6 months. There is also a thin walled, bright yellow tubing from Motion Pro that seems to be holding up well.
 
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The lines go brittle because gasoline leaches the plasticizer out of the PVC tubing. Modern tubing designed for gas and oil like Tygon F-4040-A should be a better choice. The downside is the translucent yellow color and it is somewhat less flexible than regular PVC. There is also a clear version from another company (Excelon) that is supposed to be fuel resistant. I have made a set of lines from the latter, but it has only been holding fuel for about 6 months. There is also a thin walled, bright yellow tubing from Motion Pro that seems to be holding up well.
You say "yellow" like it's a bad thing...
 

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