Bought a 95 XR500R a few weeks back. It had been sitting, gas had turned, ran rough. Went thru the carb and cleaned everything up. Checked the float height, needle and seat looked OK. Dumped gas tank. Now runs like a scalded dog...with one exception....Seems like every time I start riding, it cuts out on me once early in the ride and I have gas dumping out of the carb overflow. Once I shut off gas, drain the bowl and start over, it works fine the rest of the ride. My best guess is that I stirred up some trash in the has tank and it is getting stuck under the needle. Other ideas????