Check this youtube playlist for gold/trackmaster videos --->
https://goo.gl/w5uP6sThese videos will showcase you the driving lines to obtain these very challenging medal times.
To unlock and even try the last hardest (black series) races you will need all 160 gold medals from previous races. tracks 1-160 can be tried at anytime in multiplayer-arcade, and tracks 160-200 are available as videos if you want to see what you're up against early on.
TIP: 1st person view might help you improve your times.
IMPORTANT: Using a
JOKER does
NOT make the achievement tracker go up, so you have to actually beat the gold times. If you have already used some, those races will have a greyed out wheel in the middle of the medal logo (next to the track number in level selection)
PS. Feel free to add me as a friend on xbox if you want to practice against my ghosts, or you can do what i did and go to
https://players.turbo.trackmania.com/xb1/rankings and add all the top 10-30 players to your friends for some nice ghosts!