No you cant do the same jump over and over to unlock the colors. I tried. It will say completed but the number of jumps left will stay the same so you have to do different ones. I just went on youtube and looked for a video of someone showing all of them and marked them on the map that came with the game. Then went online and searched for them.
i unlocked lime green in downtown underground races
every time i clear the length of the jump, it add rp during the race, meaning i clear successfully
at first i thought i need to use diff vehicles for the same jump
but later on i did manage to get rp (successful jump) with my ruiner for the remaning 10 jumps or so
and unlocking lime green
first 5 or so jumps were from diff ramps i found
then 30 or so jumps from downtown underground races using diff vehicles
last 10 plus jumps were from one car only, ruiner in downtown underground races
i unlocked lime green and got airborne award
and i didnt do and cant find 50 diff ramps
so i pretty sure downtown underground races does unlock lime green for me
perhaps someone else can try
Edited by anakinroy, A week ago.