Fuel Line Options Dual Amals
- Thread starter swooshdave
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MichaelB said:
I take offense at calling them obsolete, you ride a Norton ferchrisake! :mrgreen:
Bultaco Blog
Now you know I'll never shy away from a challenge like that. Sorry, not much Norton content in this post, quick copy the links before LAB deletes it! :wink:
Ron L
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Tygon is a registered brand name of St. Gobain that encompasses a variety of polymer chemistries from PVC to silicone. If you ask for Tygon you likely will get PVC aquarium tubing unless you are careful. The translucent yellow you have looks like F-4040-A which I am pretty sure is their polyurethane tubing. In any event it is the Tygon type designed for petroleum products. The polyurethane tubing I am using is similar except it is not dyed yellow. It turns yellow, then brown soon enough! At least it stays pliable.
http://www.tygon.com/tygon-traditional-tubing.aspx
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speirmoor said:
Yes, clear but I was wondering what material it was. Obviously wondering if it stays clear and pliable.
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This is what I'm going with until I can get the right banjos.
At least now I have reserve.
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I recently converted the old H style to two banjos with two spigots per banjo. Learned a couple of things along the way.
I tried a heat gun to get the old hardened fuel line off the plastic T fittings. By the time the plastic fuel line is soft, so was the t fitting, and the fitting twisted like a twist drill.
The metal banjos resist crushing better than the plastic ones. But digging through my junk, many of the metal banjos were deformed. So they can be overtightened. If the banjo persists in leaking, it is probably because the nylon screen which doubles as a seal is hardened. Sombody told me that one solution to leaking banjos is to use a sealing washer in addtion to the nylon screen. Haven't tried that yet.
The correct banjo has spigots at 180 degrees. I had Bonneville banjos with 150 degree spigots, and they work just fine. The inner spigots line up, and the outer sticks out at 150 degrees. No big deal.
Getting the correct length of gas line joining the two banjos is very fussy. Either too long or too short and the banjos tend to cock and leak.
Stephen Hill
Victoria, BC
I tried a heat gun to get the old hardened fuel line off the plastic T fittings. By the time the plastic fuel line is soft, so was the t fitting, and the fitting twisted like a twist drill.
The metal banjos resist crushing better than the plastic ones. But digging through my junk, many of the metal banjos were deformed. So they can be overtightened. If the banjo persists in leaking, it is probably because the nylon screen which doubles as a seal is hardened. Sombody told me that one solution to leaking banjos is to use a sealing washer in addtion to the nylon screen. Haven't tried that yet.
The correct banjo has spigots at 180 degrees. I had Bonneville banjos with 150 degree spigots, and they work just fine. The inner spigots line up, and the outer sticks out at 150 degrees. No big deal.
Getting the correct length of gas line joining the two banjos is very fussy. Either too long or too short and the banjos tend to cock and leak.
Stephen Hill
Victoria, BC
DogT
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Sdave,
Why is your harness so far away from the head? You can see mine is so close I got a burn mark on one side. I even pushed the tank all the way back as far as possible. Just different location of taps?
I also notice that my original H harness had crimp ferrules on all the connections. The OB harness only has the ferrules on the in and out, not on the T. I notice too that some use clamps on the in and out, but not always on the T. Can someone explain this to me. I'm seriously thinking about going to the newer style with the 180° double spigot banjo because of my close fit. I didn't have this issue before. Maybe I made the rear shorter line too long and it's pushing the line up to the front?
I also notice Dave, that your rubber air gaskets are pushed way up over the carb, is this a secret to getting them on without taking off the carbs?
Don't you like that blue colour, it matches the paint, sort of.
Dave
69S
Why is your harness so far away from the head? You can see mine is so close I got a burn mark on one side. I even pushed the tank all the way back as far as possible. Just different location of taps?
I also notice that my original H harness had crimp ferrules on all the connections. The OB harness only has the ferrules on the in and out, not on the T. I notice too that some use clamps on the in and out, but not always on the T. Can someone explain this to me. I'm seriously thinking about going to the newer style with the 180° double spigot banjo because of my close fit. I didn't have this issue before. Maybe I made the rear shorter line too long and it's pushing the line up to the front?
I also notice Dave, that your rubber air gaskets are pushed way up over the carb, is this a secret to getting them on without taking off the carbs?
Don't you like that blue colour, it matches the paint, sort of.
Dave
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Dave,
What type of petcocks are those on your bike?
What type of petcocks are those on your bike?
DogT
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BAP from OB for about $18 each, plus shipping. I thought they were leaking, but I slathered Aircraft gasket sealant on the threads, and the top of the stat-o-seal and it seems to have stopped the dripping. Haven't had it on the road since though, maybe when the temps get out of the 90's. I wish I could get my old originals fixed for a cheap price.
Dave
69S
Dave
69S
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DogT said:
I've got those same ones. Work great, so far. :mrgreen:
danfr
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Please excuse my ignorance, as I just purchased my first commando and am in the processes of revitalizing it.
buttttttttttt.....
is it really necessary to connect the two sides of the fuels lines together? Couldn't The left petcock and fuel line feed the left carb and visa versa? It sounds like having the linked fuel line created a bit of an unnecessary hazard if the head gasket blew.
thoughts?
buttttttttttt.....
is it really necessary to connect the two sides of the fuels lines together? Couldn't The left petcock and fuel line feed the left carb and visa versa? It sounds like having the linked fuel line created a bit of an unnecessary hazard if the head gasket blew.
thoughts?
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danfr said:
If everything is as it should be, then the tank should have one 'main', and one 'reserve' fuel tap? Connecting each tap to only one carb would involve removing the standpipe from the main tap or replacing it with a second reserve tap, in which case there will be no reserve fuel supply. Another alternative would be to replace both taps with two that have main and reserve positions.
However, a simple alternative would be to fit the later Commando fuel line which has the connection between the carb banjos.
http://www.oldbritts.com/13_065192.html
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DogT said:
I've just checked through the '68-'70 parts book which lists: "033145...Petrol tap (main)", and "031746....Petrol tap (reserve)" and "009195 Reserve transfer" for '68.
The information in the '69-'70 supplement sections doesn't suggest there was any alternative tap arrangement for the '69-'70 models.
I you are feeling particularly aggressive on a particular day, the reserve can come up particularly soon. I would not leave home without a reserve, not that I'm being particular or anything.
I have always gone with 150 degree offset connections on the carbs, http://www.amalcarb.co.uk/ProductDetail.aspx?Id=652, with a short tube connecting in between them. They tuck in nicely and offer a slightly cleaner routing. Thus the left (main) petcock feeding both barbs from the left and the right (reserve) petcock feeding both carbs from the right. Simple, clean, and totally effective.
I have always gone with 150 degree offset connections on the carbs, http://www.amalcarb.co.uk/ProductDetail.aspx?Id=652, with a short tube connecting in between them. They tuck in nicely and offer a slightly cleaner routing. Thus the left (main) petcock feeding both barbs from the left and the right (reserve) petcock feeding both carbs from the right. Simple, clean, and totally effective.
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