In comparison to "Marathon" in Trials HD, this achievement is much easier. The tracks aren't as bad, there's only 6 of them, and it's less than half the length. You still need to be quite good at the game though.
You must complete the Medium difficulty tournament named "Scenic Route" without faults. The tracks are as follows.
Cliff Jumper (Easy)
Tribal Trouble (Medium)
Falling Down (Medium)
Swamp Fever (Medium)
Around The Ranch (Hard)
The Ascent (Hard)
I recommend the Scorpion 450cc bike over the Phoenix 250cc for this tournament. I found it quite a lot easier myself this way, as the bike was more stable, and less likely to flip because of it's stats. I cut my faults down instantly by switching, however, both bikes can do the trick.
Tips:
Practice, Practice, Practice. Make sure to run through each track multiple times on it's own before going for this achievement, using the bike of your choice. You should also probably leave this achievement for last, as it is the hardest. Once you are able to get 2-3 perfect runs in a row on each track, you should start going for the achievement.
Cliff Jumper: If you can't do it, don't try for this achievement.
Tribal Trouble: Just take your time from checkpoint to checkpoint.
Falling Down: Find a path that suits your play style, and memorize the "dynamic" parts of the track as best as possible.
Swamp Fever: Slow and steady wins the race (and the tournament). This track is the least forgiving if you go too fast. Take your time through the obstacles.
Around the Ranch: The hardest track of all of them, in my opinion. Practice this one as much as possible, and make sure you are able to do the fire obstacle consistently.
The Ascent: This track is actually quite a lot easier with the Scorpion than the Phoenix. Take you time between obstacles, and don't reset your rider by accident if you start rolling backwards.
Everyone will probably find a personal route they are comfortable taking through each level. The trick is to find a route that suits you, and that you can perform consistently without faults. I recommend the ones I use in video as they work for me and others, but some people may have trouble with certain approaches of sections.