Extra tubes?

[hot_wax_tree]

Hey i have a 1981 GS550t and I switched out the carbs but it has been a long time since I took the old ones out. now the tank on this bike has to feeds for fuel. one for reseve and another for the main fuel line. this comes out from between the two middle carbs. But inbetween the other two pairs there are also tubes. I have no idea where these tubes lead to. If you know I would greatly appriciate it if you could inform me.
Thank you
Jake

[tkent02]

Should be vents....

Not familiar with your 550 but on my 750, the other two go down behind the airbox through a little slot and just end down in front of the swingarm.

[Peter]

Hi Jake,

If you're running stock CV carbs, those other two tubes are bowl vents. You can run the hoses back under the seat (personally don't like that idea) or just leave them open. On my 750L, the left hand tee had broken off years ago and I just left it alone. The only time anything weird came out of it was when my float valve o-rings went bad. It poured gas out of there like crazy at times. It's probably best to protect them from dust (and route fuel away from a hot engine) but so far I haven't had any problems.

For the lines coming from the tank, the port closest to the head supplies vacuum to the petcock. The impossible-to-reach one in the back takes fuel. I'm assuming stock, of course. I've seen some funky stuff on these old bikes.

[Steve]

Are you SURE your two lines from the tank are "main" and "reserve"? 8-[

You have the "main" one correct, as it is the one that goes to the "T" between carbs 2 & 3. You did not say where the other tube is connected, but I will bet that it goes to either carb 2 or 3. This is NOT a reserve line. It is the vacuum line that turns on the petcock when the engine is running.


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