IRL, Wheelie bars are easily adjustable. It would be very nice to have an actual wheelie bar instead of the static "Bumper" that's in the game now. Could be done like a Suspension part, Have a Ride height adjustment. If you wanted to get fancy with it, It could be Exactly like a suspension part, with a Shock and spring in the files. Ride height and compression/rebound adjustments. But that's a Bit unrealistic, Because they do have Give, But, not really compression.