[lemming]

Leaning your weight left to straighten it out? 

So, hands off the bars, it drifts right. To stay straight while hands are off, I have to pressure the left peg. I should say that this is over a very short stretch, and with my hands around the bars close enough to simply squeeze and grab hold. Still not exactly safe.....

[Ducati Scotty]

Check the wheel alignment.

[motorman2whel]

It does sound as if the fork clamp bolts are not tight enough if its easy to flex the forks with the bars while your holding the wheel between your knees. It should take quite a bit of force to do that if the clamps are torqued to spec. But you may have a alignment problem too.

[ROVERMAN]

My B5 pulls to the right when hands off. It is not rider error or my fat arse being off set. My 03' Iron barrel ran as straight as a die.I find it quite difficult to alter the bikes direction using body "English" when my hands are off the bars. I set both of my Enfields up the same way as far as alignment goes.
Roverman.

[Vince]

     Any vehicle will drift to the right on most roads. Roads are crowned for water run-off. Corners are banked to aid turning.
     Body position affects turning or drift. Road racers shift to the inside of the corner and even hang their leg out. Dirt riders weight the outside peg to help maintain traction and direction in a corner. Street and dirt riders press the tank with their knees to aid direction changing. A passenger leaning away from a turn as you lean in will cause you to swing wide. 
     Even if you were able to find a table top level road, the bike would drift one way or another depending on your body position.