New Shimano 105 Di2: Road bike groupset now 12-speed and with wireless shifting

On the 40th anniversary of its market launch (1982 under the nickname Golden Arrow), Shimano is giving the 105 road bike groupset an electronic upgrade. The new Shimano 105 Di2 with the abbreviation R7100 will be available as an electronic shifting system for the first time. Until now, Di2 technology ("Digital Integrated Intelligence") has been the sole preserve of the top Dura-Ace and Ultegra road bike groupsets since their introduction in 2009. From 2023, the 105 Shimano groupset will also change gears electronically rather than mechanically for the first time. And even wirelessly. This is because the new 105 Di2 inherits the wireless communication between shifters and rear derailleur that Shimano introduced last year with the Top groupset Dura-Ace R9200 and the current 12-speed Ultegra Di2 presented. The Shimano 105 also gets a sprocket on the cassette and thus joins the ranks of the 12-speed road bike drivetrains. At the same time, however, the Di2 upgrade also drives up the price. In the past, the Shimano 105 was always the Japanese company's road bike drivetrain that offered high-quality technology at a fair price and was therefore fitted to many entry-level road bikes. According to Shimano, however, the affordable mechanical ensemble will continue to be built and offered as an eleven-speed drivetrain until further notice.

105 Di2: A mixture of radio and cable

Like the other electric drivetrains from Shimano, the new 105 Di2 is not completely wireless, as is the case with the Sram electric drivetrains (eTap AXS and XPLR). Instead, a combined system is used: the shifters communicate wirelessly with the rear derailleur and front derailleur, but the front derailleur and rear derailleur receive their power via cable from a central battery, which is usually housed in the seat tube. The new 105 Di2 should therefore shift as quickly and precisely as the Ultegra Di2 R8100 in the TOUR test could prove.

The central component of the 105 Di2 is the rear derailleur. This not only receives the radio signals from the shifters and transmits them to the front derailleur. The charging cable is also connected directly to the rear derailleur. As with the other Shimano Di2 drivetrains, the system can be configured to your own preferences via the E-Tube app (e.g. number of gear changes when the button is held down or Synchro-Shift function). The shift/brake levers on the 105 Di2 also have the revised design of the top groupsets. Higher horns and a more ergonomic lever shape should ensure that they are easier and more intuitive to operate and have a wider grip position.

Gear ratios of the new 12-speed gearstick

As the new 105 Di2 no longer comes with eleven but 12 sprockets on the cassette, it catches up with Shimano's top groupsets and the current state of the art. As with the Ultegra, there are only two sprocket sets in the 105 Di2 series: However, the gradations are somewhat "tamer" and are 11-34 and 11-36 teeth. There are also only two variants of the 12-speed crankset in the new Shimano 105: The compact version with 50/34 teeth and a sportier 52/36 gradation. With regard to the wheels, the 12-speed components are backwards compatible. This means that existing road bike wheels with an 11-speed freehub can also be used with the new 12-speed cassettes.

What happens to the mechanical Shimano 105?

With the introduction of the new Di2 version of the 105, the question naturally arises: Will the mechanical version disappear? No! The existing mechanical Shimano 105 R7000 will continue to be available. The road bike groupset will continue to run as a mechanical 11-speed groupset and should therefore continue to be found on many entry-level road bikes between 1000 and 2000 euros.

The weights of the Shimano 105 Di2 at a glance

• Rear derailleur: 302 grams
• Front derailleur: 142 grams
• Crankset (50/34 teeth/172.5 mm): 766 grams
• Cassette (11-34): 361 grams
• Chain: 252 grammes
• Shift/brake lever (pair): 423 grams
• Disc brakes (pair): 392 grams
• Brake discs (pair): 286 grams
• Battery: 53 grammes
• Cable/small parts: 19 grams

The weights are manufacturer's specifications. In total, the new Shimano 105 Di2 should weigh 2743 grams as a complete groupset with disc brakes. In the TOUR test lab, we measured the Ultegra Di2 R8100 to be around this weight. As the individual components of the 105 Di2 are all a few grams heavier than those of the Ultegra, the real weight should end up being around 3000 grams. This means that the additional weight of the 105 Di2 compared to the Ultegra Di2 would be around 300 grams. The difference would therefore be roughly the same as between the Dura-Ace (2435 grams/TOUR measurement) and the Ultegra (2789 grams/TOUR measurement).

This is what the new Shimano 105 Di2 costs

Shimano has given us the RRP prices for the new Di2 components of the 105. For comparison: The mechanical eleven-speed version of the 105 currently costs around 700 euros in online shops.

• Cassette CS-R7100: 79,95 Euro
• Front derailleur FD-R7150: 164,95 Euro
• Crankset FC-R7100: 184,95 Euro
• Rear derailleur RD-R7150: 284,95 Euro
• Chain CN-M7100: 38,95 Euro
• Shift brake lever incl. disc brake (single): 359,95 Euro
• Brake disc SM-RT70: 36,95 Euro
• BT-DN300 battery: 194.95 euros
• Cable: 35-40 Euro

Cannondale is the first complete bike manufacturer to announce prices for its models with the new Shimano 105 Di2. The SuperSix EVO is set to cost €4,299, while the Synapse LE marathon model is priced at €4,699.

The 105 disc brakes also receive a technology update

As with the Shimano groupsets presented last year, the new 105 also comes with revised and improved hydraulic disc brakes. They should be more powerful, less susceptible to noise and easier to bleed than the previous version. They should therefore be as powerful and sensitive to modulation as the previous version. the disc brakes of the Dura-Ace, which TOUR has already tested. has.

New, attractively priced carbon wheels

For the market launch of the 105 Di2, Shimano is also presenting two new carbon wheels in the mid-price range for the first time, which are not linked to a groupset. As with the groupsets, the Japanese are transforming the technologies from the top products to more affordable components. The lower C32 wheel is aimed at climbers thanks to its lower weight, while the new C46 all-round model is based on the familiar C50 wheelsets from Dura-Ace and Ultegra.

Shimano carbon wheel C32

• 32 mm rim height
• Inner width 21 mm
• 11-speed & 12-speed compatible
• Weight: 665 g (front wheel)/ 839 g (rear wheel)
• Total weight: 1502 grams
• Tubeless ready
• Price: 1249 Euro

Shimano carbon wheel C46

• 46 mm rim height
• Inner width 21 mm
• 11-speed & 12-speed compatible
• Weight: 719 g (front wheel)/ 893 g (rear wheel)
• Total weight: 1610 grammes
• Tubeless ready
• Price: 1249 Euro