My bike seems kind of "squirrely" lately, not so much in corners as in straight roads and sweepers. The other day I stopped at a light where the lane had various dips & patches and as I slowed the whole bike was twitching left & right. Sort of like you might expect if a lot of gas was sloshing around in the tank. I put it up on a center stand with the rear wheel off the ground and found that with some effort I could move the swingarm sideways about 1/16" - 1/8", measured at the axle. I only have 2500 miles on it. Is this normal?