Kirby Air Ride/Top Ride

Challenge #55

 * Description: "Time Attack: Cross the goal 30 or more times!"
 * How to Unlock: Simply complete 30 time attacks (150 laps). This will take about 13-30 minutes to achieve.

Challenge #69

 * Description: "Top Ride: Race one lap without hitting a wall and finish 1st!"
 * How to Unlock: As with any challenge, you'll want to remove any excess NPCs (a 1v1 race). If you have a friend, they can help knock away the enemy, but remember that some power-ups could also get in the way of completing this challenge.  An easy level to complete this on is Light, since it only has two turns with a pretty wide space.

From the start, head up, then tap three times or more as you go around the turn (the more you tap, the sharper you can turn on a dime, however too many taps will slow you down and can be unnecessary). This technique can be a little confusing so try it out until avoiding the walls is a piece of cake. If you're good (and perhaps lucky) enough, you can complete this challenge without using items, shortcuts, or the boost (however these things are a risk: they can either really give you an advantage or destroy your chance at completing the challenge).
 * Light