Hm. Where exactly are you in mexico? Is it where you have to set the mayan calendar, seing all those statues rise. etc?
Place your bike at the right direction from beginning (to make the best start), as close at the mayan calendar as possible. Remember: You need to solve both "mayans" before the "timer" starts!. Then race to the big arena with the bike. Race a few times so you learn the track to the big arena and you get a hold on when to jump/steer away.
Time is not really critical for as long as you manage to get there without being killed.
Mb: Asus P5W DH Deluxe
Cpu: C2D E6600
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3D:100" passive projector polarized setup + 22" IZ3D