Often seen as the first ‘proper’ groupset in Shimano’s road component range, the ten speed Tiagra 4700 groupset has seen a raft of trickle-down updates to see it brought even further in line with higher level Data-Ace, Ultegra and 105 systems.
In the past Shimano has relied on the non-series ST-RS405 dual control shifter and brake units for any bike or rider wishing to run hydraulic disc brakes with the Tiagra groupset. The new Tiagra brake/shift levers mimick the slim shape and lever profile of the higher end units used with the more expensive groupsets. The guts of the shifting mechanism within the lever body has also been upgraded from the non-series levers to provide quicker rear gear shifts. Allowing riders to shift quickly through the cassette with a single lever throw or rapid clicking to gear up for a sprint or gear down for a climb.
An optional extra feature with the new TIAGRA Dual Control Levers, also found at 105 and Ultegra levels, is a version with a short reach lever and more outboard profile for riders with smaller hands, creating a more tailored and confidence-inspiring riding experience.
Meanwhile, a lower 48-34T front chainring combination for the Tiagra FC-4700 2-piece crankset now appears alongside the existing 52-36T and 50-34T cranksets. This smaller ratio closes the gap to 14T between the big ring and small ring, reducing the number of compensation shifts needed in the rear cassette and making Tiagra more in line with a wider number of riders.
Finally, a new 12mm E-THRU hubset (HB-RS470/FH-RS470) for disc brakes appears at Tiagra level. When combined with compatible frames, thru-axles increase the rigidity of the wheel and allow for more accurate alignment of disc brakes. This 10 or 11-speed hubset is available for 28H or 32H rims and comes with a disc brake-specific O.L.D. of 110 and 142mm respectively.
Expect to see the new, updated Tiagra 4700 available from June 2019.