I would say if removing the valves fixes the problem, then the valves themselves were the problem. You have nothing to lose taking them out. This problem is so commonplace I don't know why KAWI doesn't just put the removal instructions in the owners manual.

 

^^ +1


Pull the valves. They were probably put in to satisfy some legislation that said a fuel tank cannot be vented directly to the atmosphere or something.


OP I hear your concern, but tell you "no worries". Your problem is common and the fix is well known. And when I say fix, I mean exactly that. Pulling the valves (orange diaphrams) FIXES a design flaw, doesn't just mask a problem.

 

Yup, sounds like a tank cap vent issue. It's also possible something has clogged up the Cali spec evaporative emissions system, for which the resolution would just be to remove the whole damn system. Did that long ago on my bike.

Where are you located in California? If you're in or near the San Francisco Bay Area, I can help you out with any service and for a hell of a lot cheaper than any shop.

 

http://www.ex-500.com/8-general-discussion/14432-key-hole-not-tank-vent.html

 

Thanks!

Thanks guys,
You've got to keep in mind that I am a stock nut. The bike ran fine before the turn-up, and I can't imagine how the valves can get messed up over three days. I feel certain that the problem is in the California add on, and would like to correct it rather than just do a work-around. But . . .
OK, I'll check the valves.
saabnut, thanks for the offer, but I'm in LA

 

I am a stock nut.

I am too, sort of. I have a few mods wink2 but I can put everything back to 100% stock with the parts in my garage other than having drilled holes in the forks for drain screws and one in the dash for a voltmeter LED. Other than those 3 little holes, I can return my bike to exactly the way it was when I rode it off the dealer's lot. If you're careful with your mods, you don't have to destroy the bike in the process.

http://www.ex-500.com/wiki/index.php?title=Removing_the_California_Emissions has the details. I think the only permanent mod is removing the extra bracket that's tack-welded to the tank support bracket. You should be able to just buy another 49-state tank bracket to swap in place of your CA version (which can be safely stored away with the other parts you removed).