Lordmac
Well-Known Member
The situation: Triumph fuel tanks are built so there are fundamentally two halves separated by a tunnel which mounts to the large frame tube.
Imagine if you will, the two fuel petcocks that come stock (see photo below so you don't have to imagine) on most US import T140V Bonnevilles. Visualize that the one marked "reserve" is on the left side of the tank and the main (with that little extension tube rising up) is on the right side. Now imagine that you just ran out of fuel (on the main, or right side), and now you switch to the left "reserve" side and fuel then flows to the carbs. Okay, what about that fuel that remains in the right side of the tank which cannot flow out because the extension tube limits it? There is no balance tube under the tank which connects the right side to the left so that fuel can be used as reserve. The fuel now trapped in the right side only can be used if you get off the bike and tilt it over so the fuel can drain across to the left.
The question: How come they make petcocks that do that? I mean, is that dumb, 'er what? If there were a balance tube under the tank which connects the two sides, then the extension tube on the main petcock would make sense. But without such balance tube, in my opinion, both petcocks should drain all the fuel on their respective sides. Does anybody have a tank different than the one I have?
Imagine if you will, the two fuel petcocks that come stock (see photo below so you don't have to imagine) on most US import T140V Bonnevilles. Visualize that the one marked "reserve" is on the left side of the tank and the main (with that little extension tube rising up) is on the right side. Now imagine that you just ran out of fuel (on the main, or right side), and now you switch to the left "reserve" side and fuel then flows to the carbs. Okay, what about that fuel that remains in the right side of the tank which cannot flow out because the extension tube limits it? There is no balance tube under the tank which connects the right side to the left so that fuel can be used as reserve. The fuel now trapped in the right side only can be used if you get off the bike and tilt it over so the fuel can drain across to the left.
The question: How come they make petcocks that do that? I mean, is that dumb, 'er what? If there were a balance tube under the tank which connects the two sides, then the extension tube on the main petcock would make sense. But without such balance tube, in my opinion, both petcocks should drain all the fuel on their respective sides. Does anybody have a tank different than the one I have?
