KZ650 Fuel Petcock fails on the way to work...

Well, I left for work this morning (it was definitely a beautiful one at that, clear skies, 68 degrees, birds are chirpin, the sun is bright, just awesome riding weather) and then after about 1/2 mile onto the interstate my bike starts running on 2 cylinders, and I'm thinking, "What the hell? Why are you doing this?" So, I pull over, and step off the bike and look around, and I see fuel spots on top of the pod air filters, so I look up at the petcock, and I see that there is a leak coming from the bleed off channel, I guess this means I need to rebuild my petcock.. So then I had to call a ride, and ended up being 2 hours late for work after picking the bike up.... This sucks....

You state: "... I look up at the petcock and I see that there is a leak coming from the bleed off channel."

What are you calling "the bleed off channel"? Ed

This.

That's a picture of a Yamaha XS650 petcock. Is that the type you have on your bike? Maybe a previous owner pulled a switcheroo.

If so, take a look at the link below for details on how to rebuild. Ed

www.xs650.com/forum/showthread.php?t=20662

No, I just searched google for a reference image... The KZ650 C3 Petcock has the same little channel on it. That is where it is leaking from. I can take a picture when I get home.

If it leaks there it means the diaphragm has torn. Kawasaki diapram kit is really cheap, or at least it was last time I bought one. Only use the factory diaphram.

If the diaphragm fails, I think you should be able to switch it to PRI so that you can get home. I actually rode my bike a couple of weeks like that, with the vacuum line removed & the ports capped. ON-RES functioned as off & PRI as ON. confusing, ain't it.

Edit: I forgot to add that you may have to remove the vac line & cap the ports, because if the diaphragm is torn, it'll act as a vacuum leak, so the bike may run poorly. I happen to keep spare vac caps in the tool tray, along w a few zip ties & cotter pins.

martin_csr wrote: If the diaphragm fails, I think you should be able to switch it to PRI so that you can get home. I actually rode my bike a couple of weeks like that, with the vacuum line removed & the ports capped. ON-RES functioned as off & PRI as ON. confusing, ain't it.

Yeah, when I switch it to prime, it gives it gas, but still leaks some around the petcock....

Would I be better off getting a Pingel, or just replacing the diaphragm? I've heard some good things about the Pingel petcocks, the downside is that it's $100+...

I'd replace the diaphram and retain the vacuum operated petcock. Pingle is fine, but not necessary, and you'll have to plug the vacuum line and turn the petcock on and off every time you ride. Not that hard, but forget and even though floats are supposed to work in the carbs, they will overflow every time on these old KZs. Add to that I doubt the Pingle has a reserve capability, which can be handy to remind that it's time to gas up before running dry.

I would disassemble & inspect the petcock before ordering anything. If the mating surfaces look fine & there's no pitting or scratches or anything, then a rebuild kit should work. I buffed the surfaces w brass wool, but steel wool would be good. Get OEM parts or K&L --- ie, made in Japan. This time you probably ought to get the complete kit, but the next time in a few years, the diaphragm assy should suffice.