Shimano GRX RD-RX810 User manual

(English)
Dealer's Manual
ROAD MTB Trekking
City Touring/
Comfort Bike URBAN SPORT E-BIKE
Rear Derailleur
GRX
RD-RX810
RD-RX812
RD-RX400
DM-GARD001-02

2
Contents
Contents ...................................................................................2
IMPORTANT NOTICE ..................................................................3
TO ENSURE SAFETY...................................................................4
List of tools to be used............................................................6
Installation/removal ................................................................7
Installing the rear derailleur..................................................................7
• Standard type ........................................................................................................................... 7
• Direct mount type .................................................................................................................... 9
Adjustment.............................................................................11
Adjusting the stroke on the high limit ...............................................11
Installing the chain...............................................................................11
Checking the chain length...................................................................11
Connection and securing of the inner cable ......................................14
• Outer casing length................................................................................................................ 14
• Connection and securing of the inner cable ........................................................................ 16
Adjusting the stroke on the low limit ................................................18
Adjusting the B-screw..........................................................................19
SIS adjustment......................................................................................20
Maintenance...........................................................................22
Replacing the pulleys...........................................................................22
Applying grease to the chain stabilizer..............................................23
Adjusting friction .................................................................................24
Replacement of the plate and the plate tension spring ...................28
• Removal .................................................................................................................................. 28
• Installation .............................................................................................................................. 31

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IMPORTANT NOTICE
IMPORTANT NOTICE
• This dealer's manual is intended primarily for use by professional bicycle mechanics.
Users who are not professionally trained for bicycle assembly should not attempt to
install the components themselves using the dealer's manuals.
If any part of the information on the manual is unclear to you, do not proceed with the
installation. Instead, contact your place of purchase or a distributor for assistance.
•Make sure to read all manuals included with the product.
•Do not disassemble or modify the product other than as stated in the information
contained in this dealer's manual.
•All manuals and technical documents are accessible online at https://si.shimano.com.
•For consumers who do not have easy access to the internet, please contact a SHIMANO
distributor or any of the SHIMANO offices to obtain a hardcopy of the User's Manual.
•Please observe the appropriate rules and regulations of the country, state or region in
which you conduct your business as a dealer.
For safety, be sure to read this dealer's manual thoroughly before use, and
follow it for correct use.
The following instructions must be observed at all times in order to prevent personal injury
and physical damage to equipment and 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 cause personal injury or
physical damage to equipment and surroundings.

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TO ENSURE SAFETY
TO ENSURE SAFETY
WARNING
• Be sure to follow the instructions provided in the manuals when installing the product.
Only use SHIMANO genuine parts. If a component or replacement part is incorrectly
assembled or adjusted, it can lead to component failure and cause the rider to lose
control and crash.
•Wear approved eye protection while performing maintenance tasks such as
replacing components.
Be sure to also inform users of the following:
• Clean the chain and QUICK-LINK with an appropriate chain cleaner regularly. Intervals
between maintenance depend on the use and riding circumstances. Never use alkali
based or acid based solvents such as rust cleaners. If those solvents are used the chain or
QUICK-LINK might break and cause serious injury.
•Check the chain for any damage (deformation or cracking), skipping, or other
abnormalities such as unintended gear shifting. The chain may break, and you may fall. If
any problems are found, consult your place of purchase or a distributor.
When using TL-CT12:
•Be careful not to get injured by the blade or needle while working.
•Be careful not to get your fingers pinched by the tool while working.
•Keep the tool out of the reach of small children.
NOTICE
Be sure to also inform users of the following:
•For SHADOW RD+, be sure to check that the plate unit cover and the plate unit rubber
cap are installed before riding the bicycle.
•If gear shifting operation does not feel smooth, consult the place of purchase for
assistance.
•The gears should be periodically washed with a neutral detergent then lubricated. In
addition, cleaning the chain and QUICK-LINK with a neutral detergent and lubricating
them can be an effective way of extending the life of the chain and QUICK-LINK.
•Products are not guaranteed against natural wear and deterioration from normal use
and aging.

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TO ENSURE SAFETY
•For maximum performance we highly recommend SHIMANO lubricants and maintenance
products.
For installation to the bicycle, and maintenance:
•Depending on the shape of the frame, the rear derailleur may interfere with the
chainstay. Use the B-screw to adjust so that the rear derailleur does not interfere with
the chainstay.
•Grease with SIS SP41 grease (Y04180000) the inner cable and the sliding portions of the
outer casing before use to ensure that they slide properly. Do not let dust adhere to the
inner cable.
•To ensure smooth operation, use OT-RS900 outer casing for rear derailleur and a cable
guide.
•Use an outer casing which still has some length to spare even when the handlebars are
turned all the way to either side. Furthermore, check that the shifting lever does not
touch the bicycle frame when the handlebars are turned all the way.
•The end of the outer casing which has the sealed outer cap (aluminum type) should be
on the shifting unit side. Refer to the ST-RX810 dealer's manual for details.
Shifting unit side
Sealed outer cap
(aluminum type)
Cap with long tongue
•If gear shifting adjustments cannot be carried out, check the alignment of the dropout
and check if the cable is lubricated or if the outer casing is too long or too short.
•Periodically clean the shifting unit and lubricate all moving parts (mechanism and
pulleys).
•If you hear abnormal noise as a result of excess play in a pulley, you should replace the
pulley.
The actual product may differ from the illustration because this manual is
intended mainly to explain the procedures for using the product.

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List of tools to be used
List of tools to be used
The following tools are needed for installation/removal, adjustment, and maintenance
purposes.
Tool
2 mm hexagon wrench
3 mm hexagon wrench
4 mm hexagon wrench
5 mm hexagon wrench
5.5 mm spanner
Cross head screwdriver [#2]
TL-CT12

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Installation/removal
Installing the rear derailleur
Installation/removal
Installing the rear derailleur
TECH TIPS
•The rear derailleur will not gear shift properly if the derailleur hanger is not straight.
Use TL-RD11 to check whether the derailleur hanger is straight or not.
Standard type
1. Set the switch lever in the OFF position.
Switch lever
ON
OFF

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Installation/removal
Installing the rear derailleur
2. Tighten the rear derailleur fixing screw.
Be careful not to insert the rear derailleur fixing screw in the derailleur hanger at an
angle.
In addition, be sure to install the rear derailleur so that the stopper plate contacts the
B-tension stop, with no gap in between.
Stopper plate
Rear derailleur fixing screw
Stopper plate
B-tension stop
8 - 10 N·m
NOTICE
•Periodically check to make sure that there is no gap between
the B-tension stop and the stopper plate. If there is a gap
between these two parts, problems with gear shifting
performance may occur.

9
Installation/removal
Installing the rear derailleur
Direct mount type
1. Set the switch lever in the OFF position.
Switch lever
ON
OFF
2. Remove the bracket axle plate.
RD-RX810/RD-RX812 RD-RX400
3. Install the rear derailleur.
(1) Insert the derailleur hanger into the installation part for direct mount of the rear
derailleur.

10
Installation/removal
Installing the rear derailleur
(2) Install the rear derailleur with the B-axle2.
Derailleur hanger
(1)
B-axle2
(2)
8 - 10 N·m