How do you defeat wizpig in diddy kong racing

To beat Wizpig the first time, make sure you're using Bumper and start the race. You have to hit every zipper on every lap; if you miss more than one you can't win. Remember to let off the gas right before you hit the zippers for added boost! If you hit all the zippers and get that extra boost you'll beat him with ease!
Beating Wizpig the second time is actually easier than the first if you're using Diddy Kong. First, turbo start and immediately grab the first blue ballon, use it right away and stay low. (It is very important to make all the turns, without hitting the sides of the walls and caves.)
Second, grab the first red ballon (low route) then the second, giving you a heat seeker. You should be close behind him, fire away and fly high. The high route gives you a turbo boost going into the caves; use it immediately (it is possible to pull into first going into the caves.)
As soon as you're in the caves, get the first blue ballon on the left, use it and stay low, this should definately boost you in front of wizpig. Stay low and don't worry about any other ballons until you see the Shield ballon on the left. Make sure you get it, you will need it to make it through Wizpig's chamber. Use it as soon as the space ships start shooting. If done correctly, you will stay in front of wizpig the rest of the race.
For the second and third laps, get only the blue ballons as before, avoid all red ballons, and make sure you get the shield ballon, he normally will never pass you once you pull ahead, as long as you don't hit walls. If he does pull ahead, you will only need one red ballon, then you should be able to pass once again.