Shimano tiagra drivetrain the shimano tiagra groupset got a revamp in 2016 in its looks design and technology following on from its older brothers it offers clean looks great shifting and excellent performance the chainset features the 4 arm spider bringing it inline with 105 ultegra and dura ace using a 5034 compact gearing you can tackle even the steepest climbs with confidence 10 speed tiagra sti levers offer improved ergonomics smoother shifter and lever movement under tap