Bike Stalls

[Gonzo49i]

I have a 2004 R1150R witgh an intermittant stalling problem. This has happened when I take off from a dead stop ie sitting a light in 1st gear give throttle. I hear a small backfire and the engine dies. i can start the engine up immediately. Other times the bike has stalled when down shifitng into the lower gears ie 3rd to 2nd or 2nd to 1st. The bike idles under 1000RPM. It seems to happen less frequently if I leave the enricher just above the lowest click. Any help would be appreciated.

[Sunbeemer]

Need more info - mileage, last service, how long has this been happening, have you checked for water in the tank?

[Gonzo49i]

The bike has 21K on the odometer. It was last serviced at 18.5K. I use the bike daily and gas up at a busy local station with no history of water problems. I have run a fuel injector cleaner. The problem is intermittant. One day it runs perfectly, the next who knows. Sometimes it will stall just once and other times at every stop or down shifting to a stop I have not noticed any changes in fuel economy. It ranges between 45 - 50.

[Sunbeemer]

Based on your bike's low mileage and recent service, I think it's probably a simple problem, like a vacuum leak.
First, inspect the rubber vacuum lines where they fit onto the brass nipples under the throttle bodies. These can crack and admit air. If they look ok, check where they connect to the carbon canister. If all looks good, then I'd check for leaks in the seals between the throttle body and cylinder head. Easy way to do this is spray WD-40 sparingly first around the flat face seal at the head and then around the o-ring seal between the outlet of the throttle body and the tube that connects it to the head. If you hear the bike suddenly change rpm, you found the leak!

Good luck, and let us know what you find.