Shimano Ultegra R8170 Di2 Disc Groupset

The Shimano Ultegra 8100 DI2 groupset is a semi-wireless electronic gear shifting groupset with disc brakes. This groupset provides you with one of the best braking and shifting performances available. Aside from that, it gives you more confidence and security in the long run.

This is because this groupset has many similarities with the Dura Ace 9200 DI2 Disc groupset. Although Shimano has saved somewhat on the materials the components of this groupset are made from, this groupset has the same improvements in terms of gear shifting speed on derailleurs compared to the Shimano Ultegra R8050 groupset.

In principle, this electronic set-up only needs to be finetuned once in a bike's lifespan. Maintenance of the braking system has also been simplified, because the system is less susceptible to brake disc rubbing or annoying noises while in use.

Shifters
The ergonomics of the Shimano Ultegra 81000 shifters have been optimised and is comparable to the Dura Ace R9200 Disc Di2 groupset. The shifters of the Shimano Ultegra 8100 fit your hand comfortably. You can easily place your fingers, and you can comfortably take on various sitting positions. Plus, the shifters are equipped with 2 button batteries which sustain the connection between the front and rear derailleur. These have a lifetime of about 1.5 years.

Drivetrain
The gear shifting speeds of the front and rear derailleur have been improved significantly, at 58% and 45% faster compared to previous Shimano Di2 derailleurs. And they've been optimised even further, especially to shift better under strain. You'll notice this immediately when climbing in a standing position or sprinting. The groupset can easily be charged via the Shimano Ultegra 8100 rear derailleur using the same charging cable as used for new Shimano power meters. The Junction box, which used to be installed in the frame or handlebars for finetuning, is no longer necessary. This technology, with all of its adjustment settings, has been integrated into the rear derailleur.

Disc brakes
The disc brakes have also been upgraded. The Ultegra brake caliper consists of two parts and has been CNC machined. Just like with the Dura Ace calipers, 10% extra space has been created between the brake pads and brake discs. This makes sure the brakes can barely rub, if at all, when you're not braking. Few things are more annoying than rubbing disc brakes during a climb or sprint! Braking power and modulation have also been noticeably improved.

Differences with Dura Ace
The differences between Ultegra derailleurs and the Dura Ace derailleurs are found in the construction and the materials used. The Dura Ace R9250 front and rear derailleurs weigh 96 grams and 215 grams respectively, versus the Ultegra R8150's 110 grams and 262 grams, resulting in a combined difference of 61 grams. The new Ultegra R8170 brake calipers weigh 282 grams per set, compared to a Dura Ace R9270 caliper set with a 233 gram weight. The weight difference between the shifters is about 32 grams, between the Dura Ace ST-R9270 (350 grams) and Ultegra ST-R8170 shifters (382 grams).

Semi-wireless
This Shimano Ultegra R8100 DI2 Disc group only has a cable connection between the battery, front and rear derailleur. The shifting performance has been lifted to an even higher level. Not only has the shifting speed been increased, you can now also shift smoothly while applying force to the pedals. Also, there's no longer a need for a junction box, but you can adjust the settings of the groupset and charge it via the rear derailleur. When the groupset is fully charged, you can cycle for about 1000 kilometres. The wireless shifters contain two button cell batteries that last about 1.5 years before they need to be replaced. The charger is not included with the groupset and is the same as the one used for the power meters.

Shimano DI2 app
All adjustments such as assigning shift buttons, shifting direction or adjusting the shifting speed can be done through the Shimano DI2 app. The function of each shift button is individually adjustable. It's still possible to use the synchronised shift or semi-synchronized shift function, in which the front derailleur shifts along automatically for the ideal chainline.

Servowave
The brakes use Shimano's Servo Wave Action. This technology ensures that the speed at which the pistons move towards the disc decreases as the pistons get closer to the disc. This maintains the engagement that Shimano brakes are known for, but greatly improves the brake modulation.

Cassettes
Hyperglide+ cassettes are available in different ratios. These ratios take into account the sweet spot between the 6th, 7th and 8th sprockets. 12 speed makes it possible to maintain the sprockets that ride best at average speeds despite large ratio differences. The cassettes come with the well-known HG mounting pattern, which is also backwards compatible with all Shimano HG 11-speed freehub bodies.

Brake maintenance
Maintenance of the brakes has been simplified. It's now possible to bleed the brake without removing the caliper from the frame, thanks to a separate bleeding port and twist valve. The new funnel and spacer for bleeding the caliper help optimise the bleeding process.

• Shimano Ultegra R8170 Front disc brake set
• Shimano Ultegra R8170 Rear disc brake set
• Shimano Ultegra R8100 Front derailleur
• Shimano Ultegra R8100 Rear derailleur
• Crankset Ultegra R8100
• Cassette Ultegra CS-R8100 11-30T 12 speed
• Shimano Ultegra R8100 12 speed Chain
• Shimano RT-CL800 160/160mm Center Lock disc brake
• Shimano RT-MT-800 160mm Center Lock disc brake
• Electrical Cable 600 mm Black
• Electrical Cable 1200 mm Black
• Charging cable 1700 mm
• Internal Battery