How do I unlock additional kart parts?

I'm looking to unlock all of the additional kart parts, but I'm not sure how to unlock them. How do I unlock additional parts for my karts?

According to GameFAQs:

You can earn 10 coins per race, 40 per cup.
Unlockable - How to Unlock
Random Part 1 - 50 coins
Random Part 2 - 100 coins
Random Part 3 - 150 coins
Random Part 4 - 200 coins
Random Part 5 - 250 coins
Random Part 6 - 300 coins
Random Part 7 - 400 coins
Random Part 8 - 500 coins
Random Part 9 - 600 coins
Random Part 10 - 700 coins
Random Part 11 - 800 coins
Random Part 12 - 900 coins
Random Part 13 - 1000 coins
Random Part 14 - 1200 coins
Random Part 15 - 1400 coins
Random Part 16 - 1600 coins
Random Part 17 - 1800 coins
Random Part 18 - 2000 coins
Random Part 19 - 2500 coins
Random Part 20 - 3000 coins
Random Part 21 - 3500 coins
Random Part 22 - 4000 coins
Random Part 23 - 4500 coins
Beast Glider - 5000 coins
Gold Glider - Connect with 100 people via StreetPass or collect 10,000 coins
Gold Standard (kart body) - Obtain a VR higher than 10,000 points or collect 20,000 coins
Golden Steering Wheel - Play 100 recent matches and use the first person gyro controls 80% of the time
Golden Wheels - Beat every cup on 50cc, 100cc, 150cc and Mirror Mode and receive a minimum of 1 star ranking for each cup to unlock