Shimano 105 R7100 12-Speed Road Bike Groupset Builder

$478.00 NZD

Taxes included. Shipping calculated at checkout.

The Shimano 105 R7100 Groupset delivers race-inspired 12-speed shifting, powerful hydraulic disc braking and versatile climbing gears at a competitive price, making it one of the best-value road bike groupsets for Australian training, racing, commuting and endurance riding.

Key Shimano 105 R7100 Groupset Features

Semi-wireless Di2 electronic shifting.
Versatile 2x12-speed gearing with 50-34T or 52-36T cranksets and 11-34T cassette options.
Hydraulic disc brakes provide controlled stopping power in dry, wet and changeable Australian conditions.
Refined road lever ergonomics improve comfort and brake accessibility for different hand sizes.
Shares important design principles with Shimano Ultegra and Dura-Ace while retaining more affordable replacement and servicing costs.

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General drivetrain specifications

Groupset family: Shimano 105 R7100
Intended use: Road cycling
Drivetrain configuration: 2x12-speed
Shifting options: Di2 electronic
Brake system: Hydraulic disc
Brake caliper mounting: Flat Mount
Compatible chain: Shimano 12-speed HG
Crank interface: Shimano Hollowtech II
Crank axle diameter: 24mm
Crank lengths: 160mm, 165mm, 170mm, 172.5mm and 175mm
Chainring combinations: 50-34T or 52-36T
Cassette options: 11-34T
Cassette freehub interface: Shimano road HG
Rear derailleur construction: Shimano Shadow RD
Front chainring capacity: 16T
Common rotor sizes: 140mm and 160mm
Brake fluid: Shimano mineral oil
Bottom bracket: Normally sold separately
Colour: Shimano 105 series black

12-speed road drivetrain

The Shimano 105 R7100 platform adds a twelfth rear sprocket while retaining familiar Shimano road gearing. The additional ratio helps create smaller cadence changes across the cassette without removing the low climbing gears required for steep roads.

Shimano Di2 electronic shifting

The Shimano 105 Di2 option provides accurate shifts through electronic motor control. This eliminates shift-cable stretch, housing friction and gradual cable contamination from the shifting process.

Wireless communication between the controls and rear derailleur reduces cockpit wiring. The front and rear derailleurs remain connected to the central battery for consistent power delivery.

Shimano E-TUBE PROJECT Cyclist

Compatible Di2 systems can be configured through Shimano’s E-TUBE PROJECT Cyclist application. Available functions include:

Shift-button customisation
Firmware updates
Rear derailleur micro-adjustment
Multi-shift configuration
Battery monitoring
Manual shifting selection
Semi-Synchronized Shift
Full Synchronized Shift

Hollowtech II crank construction

The Shimano 105 FC-R7100 Crankset uses hollow forged aluminium crank arms and an integrated 24mm steel axle. Outboard bottom bracket bearings create a broad support stance for efficient power transfer and dependable bearing performance.

The large chainring uses a reinforced construction designed to maintain stiffness during front shifts. This limits flex and helps the chain move cleanly between the inner and outer chainrings.

Shimano Shadow RD

Both mechanical and Di2 rear derailleurs use a low-profile design that places the mechanism closer to the bicycle. This improves appearance and reduces exposure to accidental impacts.

Unlike Shimano GRX and mountain bike derailleurs, the Shimano 105 rear deraillers do not use a clutch. The system is designed for sealed-road and maintained all-road use rather than rough gravel or technical trails.

Hydraulic disc braking

The Shimano 105 BR-R7170 twin-piston Flat Mount calipers provide powerful braking with controlled modulation. Hydraulic operation automatically compensates for normal pad wear and requires less hand force than many cable-operated disc brakes.

Shimano increased the space between the pads and rotor compared with the preceding generation. This additional clearance helps reduce intermittent rotor rub after hard braking, wheel changes or heat expansion.

Crank lengths

Available Shimano 105 crank lengths include:

160mm
165mm
170mm
172.5mm
175mm

Shorter cranks can reduce knee and hip flexion, increase pedal clearance and improve comfort in an aerodynamic position. Longer cranks may suit riders whose existing fit, leg proportions and pedalling style favour additional leverage.

Changing crank length can affect saddle height and overall bike fit. A professional road bike fit is recommended when moving significantly shorter or longer.

Crankset measurements

Q-factor: 148mm
Chainline: 44.5mm
Crank axle: 24mm
Pedal thread: Standard 9/16 inch
Chainring mounting: Asymmetric four-arm
Bolt circle diameter: 110mm
Compatible threaded bottom bracket shells: 68mm BSA or 70mm Italian with the correct bottom bracket
Press-fit compatibility: Determined by the frame and selected Shimano-compatible bottom bracket

Cassette fit

The Shimano 105 12-speed road cassette fits compatible Shimano road HG freehub bodies. It can normally be installed on an existing road 11-speed HG freehub without changing the driver body.

It is not directly compatible with:

SRAM XDR
SRAM XD
Shimano Micro Spline
Campagnolo N3W
Older 8, 9 or 10-speed-only road freehubs

Brake fit

Caliper standard: Flat Mount
Common rotor diameters: 140mm and 160mm
Common performance setup: 160mm front and 140mm rear
Recommended setup for heavier riders and steep terrain: 160mm front and rear where approved
Brake hose length: Selected according to frame size and routing
Rear caliper bolt length: Must match frame chainstay thickness

The Shimano 105 R7100 Groupset is ideal for road cyclists who want dependable race-inspired performance without the cost of Ultegra or Dura-Ace.

Cyclist Australia/New Zealand’s Shimano 105 Di2 review described it as all the road groupset most cyclists would ever need. The review found that shifting and braking performance were close to Shimano’s more expensive electronic groupsets, with weight, materials and selected extra functions accounting for much of the difference.

CycleTechReview published an extended-use assessment on 9 July 2024 after using Shimano 105 Di2 for road, commuting, cyclocross and gravel riding. The reviewer became increasingly positive about its electronic shifting, hydraulic braking and low maintenance requirements, ultimately regarding it as a highly capable do-it-all groupset.

Cyclist Australia/New Zealand’s Shimano 105 Di2 review described it as all the road groupset most cyclists would ever need. The review found that shifting and braking performance were close to Shimano’s more expensive electronic groupsets, with weight, materials and selected extra functions accounting for much of the difference.

CycleTechReview published an extended-use assessment on 9 July 2024 after using Shimano 105 Di2 for road, commuting, cyclocross and gravel riding. The reviewer became increasingly positive about its electronic shifting, hydraulic braking and low maintenance requirements, ultimately regarding it as a highly capable do-it-all groupset.