Sounds like a Subaru and loss of power

He is thinking one of the coils or a leg of the ignition is warming up and failing. You could carry a good plug with and hook it up right after a failure to check for spark. Or electronically troubleshoot the componets.
Wayne

An easy test for this is to lift the tank so you can access the coils and start the bike. Throw a good hair drier or heat gun on each of the coils. Heating them up shouldn't take very long and you'll get almost immediate feedback.

The fact that sitting for a minute is enough to clear the problem would lead me away from bad coils or pickups. They aren't going to cool off fast enough for it to work like you describe.

While electronics are a possibility, it sounds fuel related to me too.

Next time, pull over and, without turning the bike off, pop the tank cap. If the problem disappears, you've found your culprit.

If the problem is crud on the petcock screens, stopping the bike and turning it off would remove the suction that's holding the crap on, allowing them to clear and letting you go until they gunk up again.

I'd go with Patton on this one - it sounds like sand, emulsified water, or sediment from a bad tank of gas is clogging up your primary petcock filter. Check your inline filter and make sure it isn't clogging up too (or instead). A good, high flow lawnmower filter is a really good choice here - car filters assume a fuel pump, which you don't have.

I had a very similar problem on my KZ650 years ago. Everything was running fine at 75 mph then all of a sudden started running on three cylinder. At idle the engine ran great but once going down the road it woul do this. After much trouble shooting turned out to be a large bit of crud was at the bottom of number 2 carb float bowl. It was laying right at the bottom of the drain. Everytime I would roll on the throttle that bit of debri would suck up onto the bottom of the main jet starving that cylinder of fuel. Took about a day of frustration and trouble shooting.

:ohmy: if your tank has rust :pinch: :pinch: , no fuel filter will stop it from stopping up the carburetors......the red rust is too fine and the filter will usually let it go right through.I've cleaned carbs off the bike for guys,their bike runs great for awhile then they bitch about the carbs not working right.....always rust in the tank. even after I forewarned them they had to have a clean rust free tank :woohoo: .......NO kreem sealer or any garbage like that :S

Thanks for all the responses everyone.

I wanted to check out the advancer just to eliminate that possibility. Got the cover off and the thing looks brand new. No rust, springs are solid. Top notch shape. Added some lube on the little parts thats shown on the pic floating around here and sealed it back up.

Took to gym today, kind of short trip and it's never had the problem on it, made it there fine but did it coming home, and pretty quickly too, maybe about 3 minutes into riding. I pulled off the road asap and checked the headers... all hot to the touch. Didn't feel that any were less than the next. Started up, went down the road and it did it again, but not as rough though. Pulled off again, same test and no change. Popped open fuel cap (turned off motor, forgot to try to leave it on and try this) and drove rest of the way home with it. Didn't do it again, but I feel it's pure coincidence that it didn't do it again.

With that said, I think the ignition is out of the question and going to drain the tank, clean it, new filter, clean the petcock and then pull the bowls off the carbs and check them out.

Hopefully there is something just laying there being sucked up like in Baldys situation. Don't see how, but you never know. Looks like my Saturday is booked now haha.

Again, thanks to everyone!

Think I figured this one out. Previous, I had a hacked up petcock on the tank that was set too always on, and had a fuel valve inline and it worked fine.

Bought a aftermarket petcock that went in place fine, but couldn't turn to the 'On' position because the lever would hit off the motor. I always had it in the 'Res' position. With it always being on the 'Res', that means it was always pulling from the bottom of the tank... the gunk, rust and dirt. Whether it was getting ran through or just stuck on the filter, it was being blocked.

I accidently broke the aftermarket petcock and forced me to go back to the hacked up one with the fuel valve and it all made sense. Thing has worked perfect so far and it's made sense. I'm still going to clean out the tank of course and get everything out of there. But think the dirty tank (and the fact that it was pulling from the Res the whole time) is the problem. Going to do it tomorrow. Kind of excited, hope this is it!