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Shimano GRX Di2 RD-RX825-SGS derailleur, 12-wheel

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RRP 442 €
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Gravel/cyclocross electronic derailleur, for Shimano 2x12 speed system, designed for Di2 electronic shifting, for 11-34 tooth and 11-36 tooth cassettes, derailleur lock, LED battery indicator, weight 310 g.

Electronic derailleur for gravel bike riding or cyclocross racing with even more precise and faster shifting.

The Shimano GRX Di2 2x12 RX825 group is optimized for riding on forest roads and trails with 48/31z chainrings. or 46/30z. in conjunction with an 11-34z cassette. or 11-36z. These ratios guarantee an extremely wide gear range, so you can spin at a comfortable cadence, whether you're cruising on the flats, racking up miles on dirt roads, or tackling massive off-road climbs.

Shimano is pioneering the semi-wireless path in electronic systems, where individual shifting components do not have their own small battery, but are powered by a single wire from a battery hidden in the seat tube, thus achieving much longer functionality and battery life.

Among other things, the derailleur has an LED battery status indicator and a lockout - ON for gravel riding, OFF for smooth terrain without uneven terrain.

Technical designation: RD-RX825
Purpose: Gravel, Cyclocross
Total capacity: 40z.
MAX number of teeth of the largest sprocket: 36 teeth.
MIN number of teeth of the largest pinion: 34 teeth.
Technology: Di2
Weight: 310 g

Product details
Groupset Shimano GRX
Gears 2x12, 1x12
Control type electronic
product ID 331946
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WARNING
For information about installing, adjusting and replacing the products which are not found in the user's manual, consult the place of purchase or a distributor. A dealer's manual for professional and experienced bicycle mechanics is available on our website (https://si.shimano.com).
For safety, be sure to read this "user's manual" thoroughly before use, follow it for correct use, and save it so that you can refer back to it at any time.
The following instructions should always be followed in order to prevent personal injury, physical damage to equipment and the surroundings. The instructions are classified according to the degree of danger or damage which may occur if the product is used incorrectly.
DANGER – Failure to follow the instructions will result in death or serious injury.
WARNING – Failure to follow the instructions could result in death or serious injury.
CAUTION – Failure to follow the instructions could result in personal injury, or physical damage to equipment and surroundings.

For items that require replacement, be sure to consult the place of purchase or a distributor.
Be sure to observe the following instructions in order to prevent burns and other injuries due to fluid leakage, overheating, fire or explosion.

DANGER
- Use the specified charging cable when charging the battery. Using any other item may lead to fire, overheating, leakage, or damage to the connected PC.
- Prevent the charging cable from getting wet, and do not touch or hold it when it is wet or with wet hands. Failure to do so may cause problems with operation or electric shock.
- Use an AC adapter with a USB port with a voltage of DC 5.0 V and a current of at least DC 1.0 A. If you use an adapter with a current rating of less than 1.0 A, the AC adapter may heat up, resulting in fire, smoking, overheating, damage, electric shock, or burns.
- Do not heat the battery or expose it to flame. Failure to do so may cause the battery to ignite or rupture.
- Do not use or leave the battery in hot or humid locations where the battery may be exposed to direct sunlight, in a closed vehicle on a hot day, or near a heater. Failure to do so may cause leakage, overheating, or rupture, resulting in fire, burns, or other injuries.
- Do not deform, modify, or disassemble the battery. Also, do not directly apply solder to the battery terminals. Failure to do so may cause leakage, overheating, or rupture, resulting in fire, burns, or other injuries.
- Do not allow metal terminals to come into contact with metallic objects such as hairpins. Failure to do so may cause short-circuiting, overheating, burns, or other injuries.

WARNING
- Do not disassemble or modify the product. This may cause the product to not operate correctly, and you may fall unexpectedly and be seriously injured.
- Always grasp the cable plug when connecting or disconnecting the USB cable or charging cable. Failure to do so may result in fire or electric shock.
- If the following symptoms occur, stop using the device and consult the place of purchase. Fire or electric shock may occur.
- If a pungent odor is emitted from the AC plug, or the plug is hot. There may be a poor connection inside the AC plug.
- If thunder is heard during charging with the AC adapter with USB port, do not touch the device, bicycle, or AC adapter. Electric shock may occur due to lightning strikes.
- Do not use a USB hub to connect the cable to the PC's USB port. Charging failure or fire due to overheating may occur.
- Be careful not to damage the charging cable. Do not damage it, modify it, forcibly bend, twist, or pull it, place it near hot objects, place heavy objects on it, or tightly bundle it. Using it in a damaged state may result in fire, electric shock, or short-circuiting.
- If the battery is not fully charged after 4 hours of charging, stop charging. Failure to do so may cause fire, rupture, ignition, or overheating.
- Do not immerse the product in fresh or salt water, and prevent the terminals from getting wet. Failure to do so may cause fire, rupture, ignition, or overheating.
- Do not subject the product to strong impact or throw it. Failure to do so may cause rupture, overheating, or problems during operation.
- Do not use the battery if it exhibits fluid leakage, discoloration, deformation, or other abnormal signs. Failure to do so may cause rupture, overheating, or problems during operation.
- Clean the chain and QUICK-LINK regularly with an appropriate chain cleaner. Maintenance intervals depend on usage and riding circumstances. Never use alkali or acid-based solvents such as rust removers. If such a solvent is used, the chain or QUICK-LINK may break and cause serious injury.
- Check the chain for damage (deformation or cracking), skipping, or any other abnormalities such as erratic shifting. If any problems are found, consult the place of purchase or a distributor. The chain may break and you may fall.

CAUTION
- Store in a safe place out of the reach of small children to prevent accidental swallowing.
- Prevent grease from adhering to the metal terminals. This may cause conduction failure.
- Do not leave the charging cable connected during maintenance.

Shimano
Road Shimano
Japanese manufacturer produces road, mountain, gravel, trekking, BMX and e-bike groupsets. They also offer a whole series of components and apparel. Their range goes from wheels, footwear, eyewear to backpacks. Shimano is a traditional manufacturer known for their quality work, which is why they are the favourite choice of amateurs and professionals.
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