The trek fuel ex 98 29er mountain bike 2018 returns with a major capability boost with a complete redesign that incorporates more travel a more aggressive geometry and the ability to fit both 29 and 275 wheels making it the perfect go to trail bike oclv mountain specific carbon is tougher than standard carbon thanks to its unique materials and lay up procedures the straight shot downtube design creates a straight connection to the steerer tube producing a lighter and stiffer