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Shimano front derailleur and rear derailleur specifications... what do they mean, really? This page explains all of them, and why they matter. I'll also briefly talk about derailleur hanger extenders and swapping derailleur cages.

Installing new bike components can be challenging. On this page I'll list all the installation guides I've written so that you can install new components with confidence. Still, if you have any questions, don't hesitate to [send me a message](/contact/).

Installation steps and images are taken from Shimano's official documentation that can be found at [https://si.shimano.com](https://si.shimano.com).

## Di2 basics
- [Installing and sizing a chain for your Di2 bike](/installing-a-new-chain-length-and-direction/)
- [Understanding Di2 derailleur specifications](/derailleur-specifications-what-do-they-mean/)

## Battery and accessories
- [Internal battery seatpost installation guide](/internal-seatpost-di2-battery-installation-guide/)
- [Internal battery Fork Steerer installation guide](/install-the-di2-battery-in-the-fork-steerer/)
- [D-Fly / Wireless Unit WU111 Installation guide](/wireless-unit-d-fly-installation-guide-ew-wu111/)
- [EW-RS910 bar end junction Installation guide](/bar-end-junction-ew-rs910-installation-guide/)
- [SC-MT800 System Information Display installation guide](/sc-mt800-sc-m9051-system-information-display-installation-guide/)
- [SC-M9051 System Information Display installation guide](/sc-mt800-sc-m9051-system-information-display-installation-guide/)
- [FC-R9100-P Power Meter Crankset](/fc-r9100p-power-meter-crankset-installation-guide/)

## Shifters and Switches
- [SW-M8050 / SW-M9050 MTB Shifter installation guide](/mtb-style-shifter-sw-m8050-sw-m9050-installation-guide/) 
- [Road / Gravel Dual Control Lever (STI) installation guide](/installation-guide-di2-wired-shift-lever/)
- [Update 12-speed wireless lever firmware (ST-R9270 and ST-R8170)](/update-the-firmware-on-12-speed-hydraulic-shift-levers/)
- [Check and replace 12-speed wireless shifter batteries](/check-di2-shifter-battery-level-and-replace-it/)
- [Pair 12-speed wireless shift levers](/pair-12-speed-di2-wireless-shifters/)

##  Front Derailleurs
- [GRX FD-RX815 Di2 front derailleur installation guide](/grx-fd-rx815-ultegra-fd-r8050-dura-ace-fd-r9150-di2-front-derailleur-installation-guide/)
- [Ultegra FD-R8050 Di2 front derailleur installation guide](/grx-fd-rx815-ultegra-fd-r8050-dura-ace-fd-r9150-di2-front-derailleur-installation-guide/)
- [Ultegra FD-6870 Di2 front derailleur installation guide](/ultegra-fd-6870-dura-ace-fd-9070-di2-front-derailleur-installation-guide/)
- [DURA-ACE FD-R9150 Di2 front derailleur installation guide](/grx-fd-rx815-ultegra-fd-r8050-dura-ace-fd-r9150-di2-front-derailleur-installation-guide/)
- [DURA-ACE FD-9070 Di2 front derailleur installation guide](/ultegra-fd-6870-dura-ace-fd-9070-di2-front-derailleur-installation-guide/)
- [12-speed FD-R9250/FD-R8150 front derailleur installation guide](/12-speed-front-derailleur-installation-and-adjustment-guide/)

### Front Derailleur high / low adjustment guides
- [FD-RX815, Ultegra FD-R8050, DURA-ACE FD-R9150 high/low adjustment bolt guide](/set-up-front-derailleur-limit-screw-adjustment-bolt-one-bolt-derailleurs/)
- [Ultegra FD-6870, DURA-ACE FD-9070 high/low adjustment bolt guide](/set-up-front-derailleur-limit-screws-adjustment-bolts-two-bolt-derailleurs/)
- [12-speed Front Derailleur high/low adjustments](/12-speed-front-derailleur-installation-and-adjustment-guide/)

## Rear Derailleurs
- [GRX RD-RX815 Di2 rear derailleur installation guide](/rd-rx805-rd-rx815-rd-rx817-di2-rear-derailleur-installation-guide/)
- [GRX RD-RX817 Di2 rear derailleur installation guide](/rd-rx805-rd-rx815-rd-rx817-di2-rear-derailleur-installation-guide/)
- [Ultegra RD-RX805 Di2 rear derailleur installation guide](/rd-rx805-rd-rx815-rd-rx817-di2-rear-derailleur-installation-guide/)
- [DURA-ACE RD-R9150 / RD-9070 Di2 rear derailleur installation guide](/rd-r8050-rd-r9150-rd-6870-rd-9070-installation-guide/)
- [Ultegra RD-R8050 / RD-6870 Di2 rear derailleur installation guide](/rd-r8050-rd-r9150-rd-6870-rd-9070-installation-guide/)
- [Micro adjust rear derailleurs using e-Tube project](/micro-adjust-di2-derailleurs-using-computer-no-levers-required/)
- [10-speed/11-speed rear derailleurs: set B-screw, limit screws, and micro-adjust the shifting](/micro-adjust-your-road-bike-di2-rear-derailleur/)
- [12-speed rear derailleurs: set B-screw, limit screws, and micro-adjust the shifting](/adjust-12-speed-di2-rear-derailleur-shifting-and-limits/)
- [Micro adjust MTB rear derailleurs](/how-to-adjust-your-mountain-bike-di2-rear-derailleur/)

featured-installation-guides

Learn how to install Di2 components and accessories using these simple installation guides. Install derailleurs, junctions, bike wiring, D-fly / Wireless modules and more. 

Derailleur specifications - what do they mean?