The FJR should not drift to the right or left, no hands. Try this:
Loosen all of the fasteners for the front forks, including the front axle and the pinch bolts. Do not make the fork tube clamp bolts too loose at the steering head, or the fork tubes will slip upward in the clamps, lowering the front end. Keep the fork tubes at the same height as original, there. With everything loose then, hold the front wheel straight between your legs (or otherwise stationary) and twist the handlebars right and left. Find the place where the front wheel is straight, and the handlebars are straight. Tighten each fastener in order, switching between left and right sides for each bolt location, starting from the top clamps. Unless you have a bent fork tube or bad steering head bearings, the FJR should track straight then.