My new project bike has a fuel system with two lines from the tank (main and reserve tubes) to a frame-mounted on-off-reserve petcock which has one outlet to the carb. The stock parts are corroded, worn, and not readily available in the U.S. Chunks and grit from the disintegrating pot metal is clogging the carb, so I am hoping to replace it with something more reliable and easier to service. Replacing the entire shebang with a single petcock would place it in a hard-to-access spot inside the frame. Does anything exist to help me? Pingel doesn't seem to make anything, and I tried a couple other spots with no luck. I could order one from Europe for 65 Euro, but for about a hundred bucks shipped and the wait, I want to investigate more local and/or more durable/serviceable options. I can fab a mount/adapter to the frame with ease. Anyone seen something like this?
http://www.cmsnl.com/products/suzuki-dr800-1992-sn_4430031d01/#.VhCoxmZHbCQ
You could use a $5 petcock, plumb the 2 lines together before the valve and do without the reserve. Or use 2 $5 petcocks, one on the main tank pickup, one on the reserve pickup, with the output of the reserve valve T'ed into the other lines. Or use one of the generic 2 tube petcocks and attache one pickup hose to each tube. The tubes don't have to be in a tank.
It would help to know what brand of tank we're dealing with.
EvanR
Dork
10/6/15 2:04 a.m.
Cool! EvanR, that looks like what I need. FWIW, the tank is a JDM 1992 Suzuki Goose 350, but the petcock doesn't mount on the tank. The tank has a fitting with two feed tubes (with Japanese 44mm bolt spacing, almost all American-market Japanese bikes are 34mm) and the feed tubes have two rubber hoses down to the petcock, mounted to some tabs on the frame.
If EvanR's suggestion doesn't work, i may also look into early 80's GSX1100, which looks to be a similar arrangement, even if the part numbers aren't the same. GS500 stuff is also similar-ish, but with a vacuum petcock, extra emissions crap, and multiple carbs, so it seems less than ideal.
OK, found a NOS GSX1100 petcock for cheap, so I think I have it sorted. Here is how it is laid out from tank at the top to carb on the lower right.
This is the old feed tubes:
And after several cleanings and several attempts to run the bike:
And this was the petcock valve when I got it! The pot metal inside the old petcock was like the picture above, grey/flaky/chalky/crumbly!
I wanted to get started tuning the Keihin, but any attempt to do so rapidly became an exercise in chasing down the clogs in the fuel system. The tank got a cleaning last night with denatured alcohol, so I hope to get it running better soon! 
