Shimano Ultegra Di2 ST-R8170 / BR-R8170 Shift Lever & Caliper, Left / Front

MPN IR8170DLF6SC100F / UPC 192790241050 / Model ST-R8170 / BR-R8170 / New

This is the complete left side of an Ultegra Di2 front end: the ST-R8170 shift lever, the BR-R8170 flat mount caliper, and the hose already cut, connected and bled at the factory. Shimano ships it as a J-kit so it goes straight onto the bike. No bleed kit, no mineral oil, no hour lost at the workbench guessing whether you got the air out.

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Will it fit your bike?

Left / front side, 12-speed Di2, flat mount caliper, 1000 mm hose

This is the left lever and front caliper. On a standard road setup the left lever operates the front brake and the front derailleur. It suits Shimano 12-speed Di2 systems (Ultegra R8100 or Dura-Ace R9200), paired with the matching rear derailleur, battery and wiring. The caliper is flat mount, the standard on modern road disc frames, and the 1000 mm hose is the correct front length for almost every frame size.

Please check before ordering: this is the left side only, sold individually, not a pair. It is Di2 electronic, so it will not work with mechanical shifting, and it needs a flat mount frame, not post mount. Message us with your frame and groupset and we will confirm before you buy.

What makes it special

Pre-bled from the factory. Lever, hose and caliper arrive connected and bled as a sealed J-kit. Bolt it on, route the hose, ride.
Semi-wireless Di2. The lever talks to the derailleurs wirelessly, so the only wire in the bar is the one to the battery. Far simpler to build than the previous generation.
Reshaped hood. The R8170 hood is slimmer and taller than the R8000, with better grip on the drops and a more natural wrist angle on the tops.
Servo Wave braking. Faster pad engagement and more power at the lever than the outgoing Ultegra hydraulic system.
Customisable buttons. Both lever buttons and the hood-top button are programmable through E-TUBE, so you can set shift logic, or run a head unit control.
Ultegra, not third-party. Genuine Shimano in retail packaging, the same lever fitted to complete bikes at this level.

The details

Brand	Shimano
Series	Ultegra R8100 Di2 (12-speed)
Model	ST-R8170 lever / BR-R8170 caliper
MPN	IR8170DLF6SC100F
UPC	192790241050
Type	Hydraulic disc shift lever and caliper set
Side	Left / front (sold individually)
Speeds	12-speed Di2 electronic
Caliper mount	Flat mount
Hose length	1000 mm, pre-bled J-kit
Brake fluid	Shimano mineral oil, filled and bled
Material	Aluminum and composite
Weight	225 g (7.9 oz)
Color	Black
Country of manufacture	Japan
Condition	Brand new, original Shimano retail packaging

Delivery & returns

Ships from California with tracking, typically arriving in 3-5 business days, dispatched within 1 business day. Free 30-day returns, we cover return shipping.

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