Riptide GP: Renegade
24 Achievements
100,000 XP
Reckless
Continuously boost for 30 seconds on any level.
2,000 XP
1.98%
How to unlock the Reckless achievement in Riptide GP: Renegade - Definitive Guide
I did it on Sky Mines as well except I didn't hit my boost after doing the first jump. I waited until I got a little closer towards the next jump. I did it in the challenge mode too.
If you wanna see it being done check out my video at 11:05
Though it might sound difficult to earn enough boost to boost for 30 seconds straight it is likely that you will unlock the trophy through natural play. If that is not the case you should make sure to attempt this with a high tier, fully upgraded hydrojet. Make sure you have used some skill points to get the Boost Bonus skill to a high level, preferably to level 4. Try your luck on either the Tropico or Sky Mines stages. Lombax & Lunchbox has made a video on how to do it:
This is easier than it sounds the best level to do it on is Sky Mines. It can be done in quick race, or career use a fully upgraded hydrojet. Make sure you have used some skill points to get the Boost Bonus skill to a high level, preferably to level 4. If you're playing on Sky Mines, when you get to the first jump, it's possible to do a level 10 stunt. Now boost and you can do more jumps off the other ramps to keep your boost up. Here is a video from Lombax & Lunchbox help.