DISCLAIMER: This report assumes the player knows very little about Wario, so there are some techs in here that are common knowledge. I do, however, believe I've found some new things.
BIKE TRICKS
-Jump, special attacks, and melee attacks cause Wario to jump off his bike. This includes all direction B-moves, and all direction aerials including the c-stick. For instance, you can side-b, then hit the c-stick right twice to jump off and f-air. The same effect can be achieved by hitting B twice, hitting B then Up-B, two up-airs, (by this I mean leaping off the bike by hitting the c-stick up, then up-air. It's just a lazy way to do it) literally anything. This allows Wario to cover the horizontal game with his bike, and the vertical game with his aerials.
-One thing you can do is leap off the bike, and hold B. Wario will fall in a straight vertical line, and you can catch opponents recovering to the stage if you time it correctly. If not, it's extremely forgiving. (Note: I find that the easiest way to catch an opponent off stage with the neutral B it to be slightly lower than them, and jumping into it. It catches them almost instantly, and can be a suicide kill if your opponent has bad recovery or if you're both far enough off stage. In some cases, you'll even manage to get back on stage with the bike and the extra jump for extra lulz.)
-Offstage, jumping off Wario's bike gives him an extra jump, meaning you can double jump off stage, bike back to stage, and receive a third jump. One possibility this creates (of several) is the ability to jump off stage, f-air, jump, n-air, bike back to stage, and recover. He can linger off stage for a stupid period of time due to his recovery. F-air and n-air in the combo listed above can both be substituted with any aerial, an air dodge, a special move, ANYTHING. Be creative. And if you're extra ******** and somehow screw up your recovery, any decently charged fart will save your stock as a last ditch effort.
-You can chase kills far off stage by driving off and hitting your opponent with it. If you jump off at the last second and use your two jumps, you can bike back and jump back to stage. As long as your bike leaves the boundary of the stage, you will get a second one.
-You can go under the stage to the other side with the bike. In this case, you don't get the bike back until you get back onstage, meaning you can't just keep biking from side to side.