How do you jump the bridge with your motorcycle on Tomb Raider?

You can't jump the bridge with a motorcycle in Tomb Raider. There are no motorcycles in the Tomb Raider games, and even if there were, the bridge would be an impossible obstacle to jump.

It sounds like you might be thinking of a different game, perhaps one with motorcycles and a bridge jump. If you could tell me what game you're thinking of, I might be able to help!