Wheelie RiderG 30

To unlock this achievement you simply need to ride a motorbike for 500 feet while doing a wheelie. This can be accomplished easily on a long stretch of road like on a bridge where traffic is manageable and won't generally run into you. You can use any motorcycle in the game as well as the scooter for the achievement. Build up some speed and pull back on the left stick to pop the wheelie and the achievement will be yours. It might take a couple of tries to get the hang of the motorbike itself, but it should be easy enough to pull off with a little practice.