new problem just cropped up.  I was riding home on the freeway, and I was wide open in 6th gear, suddenly it feels weaker, so I figure, "oh fuel starvation", so I back off the throttle, switch it to reserve and keep going.  except the engine stays really weak.  I get off the freeway and the engine is putting out barely enough power to pull away from an intersection...I limp home barely.
any idea what the problem is?
I'm 1k since the last oil change, the bike has oil and gas.  No clanking sounds.  The bike won't start unless you give it lots of gas, and then it barely puts along.  I don't see smoke from the tail pipe.  There is what looks like dried oil on the engine and around the cam chain tensioner.

thanks,
atek3

what year bike? sounds like rich's problem (phadreus)

are you running off of both cylinders? any knocking sound....is engine sound the same as usuall?

1989.  I fired it up turned it off...smelled unburned gas.  Felt the left header... cool... the left cylinder isn't firing.  I'll get a socket and pull the plug (what size socket fits a gs spark plug?) and look it over.

atek3

18mm and yes there is enough clearance to use a wrench.

check the obvious stuff first...check for a spark...also..while your in there...check the spark plug for lean/rich condition etc...

keep us posted