This great bike which is unlocked from the Ronin missions has the ability to defy gravity and climb up the side of any building in the game. What you have to do to is backup so you have enough room to approach the building and be able to do a wheelie so that the bikes front wheel touches the side of it.
When the front wheel touches you then have to accelerate. If you approach the building and just do a wheelie when you hit the side it won't work and you'll just do a burnout on the ground when you try and accelerate.
Added by: Sanzano Oct 24th 2008, ID#3343