Topic: Stock (dual outlet) petcock question

[Weeburn]

Hey all, I've noticed I have two outlets on my petcock 74 550K0, split between the four carbs (1/2 & 3/4)

I noticed the other day when I had my tank off and flipped the fuel valve open, either run on reserve, fuel was only flowing out of one of the two (rearmost) outlets. After I let it run a little today when I pulled the fuel lines off both had fuel in them.

Apparently the PO had repaired the petcock with some kind of JB weld or epoxy, and the stock screen filter was missing and replaced with a half-assed home made one, I figured maybe it was clogging one of the outlets, but after blasting both outlets with compressed air (still on the tank) Air/fuel shoots out both sides, like they're not clogged, but after the air still only one pours out. If I tilt the tank around at wierd angles I can get some to come out both, but that's not the way the tank sits on the bike.

So is it normal for one to dump fuel out, or should both? Maybe suction still draws fuel from the other one or something? Kinda confused here and new to these bikes.

[Gordon]

That's normal.  With the petcock not attached to the carbs the fuel will pour out the outlet that offers the least resistance.  When you tilt the tank around you can change which one that is at that particular time.  Nothing to worry about. 

[Weeburn]

That's normal.  With the petcock not attached to the carbs the fuel will pour out the outlet that offers the least resistance.  When you tilt the tank around you can change which one that is at that particular time.  Nothing to worry about.

Cool, thanks for the quick response.

[TwoTired]

When you are doing the outlet flow test, put your finger over the one that is flowing.
This, in essence, is what the float bowl valves do routinely.  When the outlet pipe fills, the "other" outlet flows readily.

I have both the dual outlet and the single outlet types on my 550s.
The running out of gas symptom is different between them.
The dual outlet type starves 2 carbs first, which drops the power output, but not completely, allowing some leisure time to reach down and switch to reserve.

The single outlet type starves all four at nearly the same time.  Way drastic power lost, and a more frantic switch over to reserve, particularly in traffic!

Cheers,

[Weeburn]

The dual outlet type starves 2 carbs first, which drops the power output, but not completely, allowing some leisure time to reach down and switch to reserve.

That's exactly what mine did. I didn't realize I ran my first tank dry last week  looking in the tank at fuel level I didn't know how low was too low, and when it lost some but not all power, I figured something let go somewhere and freaked out for a minute till I switched to reserve. Cool feature (Whether intended in design or just the way it is)