Shimano ST-7971

SI-6RY0A-003-00
General Safety Information
3. Install the inner cable
Gear shifting operation
3. If shifting switch (X) is pressed once, the guide pulley will move
one step toward the inside. If shifting switch (Y) is pressed once,
the guide pulley will move one step toward the outside. The guide
pulley can move 12 steps inward and 12 steps outward from the
initial position, for a total of 25 positions.
■ Rear shifting switch operation
< Shifting switch (X) >
WARNING
• When the shifting switch is operated, the motor which drives the front derailleur will
operate without stopping at the shifting lever position. Always be sure to remove the
battery before carrying out installation and adjustment, otherwise your fingers may
become stuck.
• Obtain and read the service instructions carefully prior to installing the parts. Loose,
worn or damaged parts may cause the bicycle to fall over and serious injury may occur as a
result. We strongly recommend only using genuine Shimano replacement parts.
• Obtain and read the service instructions carefully prior to installing the parts. If
adjustments are not carried out correctly, the chain may come off and this may cause you to
fall off the bicycle which could result in serious injury.
• Use the ST-7971 with the BR-7900. Do not use the BR-7900 in combination with previous
STI levers for road riding or with the BL-R770/ BL-R550 brake levers for flat handlebars,
otherwise the braking performance provided will be much too strong.
• Because of the characteristics of the carbon fiber material, you must never modify the
levers, otherwise the lever may break and the brakes may no longer work as a result.
• Before riding the bicycle, check that there is no damage such as carbon fiber peeling or
cracking. If there is any damage, replace with a new part immediately without trying to repair
the damage, otherwise the lever may break and the brakes may no longer work as a result.
• Read these Technical Service Instructions carefully, and keep them in a safe place for later
reference.
<Points to note about the handlebars>
• Handle inner diameter: 19.0 - 22.5 mm
• Handle outer diameter: 22.2 - 24.0 mm
• Applicable handlebars: Carbon fiber handlebars (with aluminum inserts where the brake
levers are installed) or aluminum handlebars
* Carbon fiber handlebars without aluminum inserts where the brake levers are installed
cannot be used.
Note
• RD-7970: Be sure to adjust the top adjustment bolt and the low adjustment bolt by
following the procedures in the Service Instructions. If these bolts are not adjusted, the
chain may become clamped between the spokes and the large sprocket and the wheel
may lock, or the chain may slip onto the small sprocket.
• Use a soft cloth to clean the carbon fiber levers, and be sure to moisten the cloth with
neutral detergent before using it, otherwise the lever material may become damaged and
lose its strength.
• Avoid leaving the carbon fiber levers in places where high temperatures are present. Also
keep them well away from fire.
• Operation of the levers related to gear shifting should be made only when the front
chainwheel is turning.
• Always be sure to use the TL-EW01 special tool to remove the cable.
• Be careful not to let water get into the terminal.
• Do not disassemble, otherwise problems may occur.
• When routing the electric cable, make sure that it does not interfere with the operation of the
brake lever.
• Parts are not guaranteed against natural wear or deterioration resulting from normal use.
• For maximum performance we highly recommend Shimano lubricants and maintenance
products.
• For any questions regarding methods of installation, adjustment, maintenance or operation,
please contact a professional bicycle dealer.
Accessories
The chain moves from a small sprocket to a
larger sprocket each time the switch is
operated.
Outer holder
6. B-tension adjustment bolt adjustment
Set the chain onto the small chainring and the largest sprocket,
and then turn the crank arm backward. Turn the B-tension
adjustment bolt to adjust so that the guide pulley moves close to
the sprocket without obstructing the chain. Next, set the chain onto
the smallest sprocket and check in the same way that the guide
pulley does not obstruct
Largest sprocket
Smallest sprocket
the chain.
Outer casing
Inner cable
< Shifting switch (Y) >
Cable hook
The chain moves from a large sprocket to a
smaller sprocket each time the switch is
operated.
When adjusting, the guide pulley will overrun slightly and then
move back in an exaggerated movement so that you can check the
adjustment direction. When checking the positions of the guide
pulley and the sprocket, check at the position where the guide
pulley finally stops.
Inner end
Make sure that the inner end is firmly
seated in the cable hook.
B-tension
adjustment bolt
Guide pulley
■ Adjustment of the front derailleur (FD-7970)
Be sure to read the service instructions for the Brake
System in conjunction with these service instructions.
Note:
4. While turning the crank arm, operate shifting switch (X) to move
the guide pulley toward the inside until the chain touches the 4th
sprocket and makes a slight noise.
The low adjustment bolt, the top adjustment bolt and the support bolt
are close to each other. Make sure that you are using the correct bolt
for adjustment.
<Adjust the lever stroke.>
Support bolt
The checker (SM-EC79) can be used to shift up and shift down
shifting switches (X) and (Y).
Top adjustment
bolt
* For details on the shifting switch selection method, refer to the
Service Instructions for the checker.
Low adjustment bolt
■ Front shifting switch operation
< Shifting switch (X) >
Turn the reach adjustment bolt with
a flat-tipped screwdriver having a
tip width of 3 mm and a thickness
of 0.6 mm.
The chain moves from the large chainring to
the small chainring.
Next, operate shifting switch (Y) 4 times to move the guide pulley
toward the outside by 4 steps to the target position.
< Low adjustment >
Refer to the Service Instructions for the electric cable (SM-EW79AI) for details on connecting the cable connectors and routing the
cable.
Operate 4 times
Set the chain onto the small chainring and the largest sprocket. Use a
2 mm Allen key to turn the low adjustment bolt to adjust so that there
is a clearance of 0.5 - 1 mm between the chain and the chain guide
inner plate.
4 steps
Adjustment
< Shifting switch (Y) >
■ Adjustment of the rear derailleur (RD-7970)
1. Install the battery.
2. Shift the rear derailleur to the 5th sprocket position. Press the
The chain moves from the small chainring to
the large chainring.
• Heat shrinking tubes x 2
• Brake cable: Long x 1, Short x 1
button at the junction (A) of the SM-EW79A until the red LED turns
on in order to switch to rear derailleur adjustment mode. Note that
if you keep pressing the button after the red LED has turned on,
protection recovery operation will begin.
There may be times when we need to send out important information
regarding our products, so we recommend that you register your product by
entering the product serial number on our website.
Press the button at junction (A) until the red LED turns off in order
to switch from rear derailleur adjustment mode to gear shifting
mode. Shift to each gear and check that no noise is generated at
any gear position. If fine
adjustment is needed, switch
back to adjustment mode and
readjust the rear derailleur.
0.5 – 1 mm
http://www.shimano.com
Turned off
Button
Janction (A)
Technical Service Instructions
SI-6RY0A-003
If the chain falls off on the inside, keep pressing shifting switch (Y)
to move the front derailleur to the outermost position in order to
reset the chain.
5. Next, carry out the adjustments for the low adjustment bolt and top
adjustment bolt.
< Low adjustment >
Button
ST-7971
illuminates red
Shift the rear derailleur to the largest sprocket, and then tighten the
low adjustment bolt until it touches the stopper.
< Top adjustment >
Next, set the chain onto the large chainring and the smallest sprocket.
Use a 2 mm Allen key to turn the top adjustment bolt to adjust so that
there is a clearance of 0.5 - 1 mm between the chain and the chain
guide outer plate. Move the front derailleur and the rear derailleur to
all gear positions, and check that the chain guide does not touch the
chain.
Installation to the handlebars
Dual control lever
1. Pass the outer casing through the handlebar, and then adjust its
For time trial bar / shifting switch on top of aero bar
In order to realize the best performance, we recommend that the following
combination be used.
Series
DURA-ACE
Dual control lever
Be sure to leave some excess cable, even if cutting it to the full
length of the handlebars.
2. Install the brake lever to the handlebar by using a 5 mm Allen key
to turn it counterclockwise as shown in the illustration.
ST-7971
Electric cable
Note: The knurled grooves should be
SM-EW79A-I
Battery / Battery charger
aligned.
SM-BTR1 / SM-BCR1
Gears
<Protection function>
2 mm Allen key
If the bicycle receives a strong impact, the protection function
operates and the connection between the motor and the link is
momentarily severed so that the rear derailleur will no longer operate.
This is done in order to protect the system at times such as if the
bicycle falls over. If this happens, press the button on junction (A) of
the SM-EW79A for 5 seconds or more. This will restore the
connection between the motor and the link and clear the protection
function for the rear derailleur. Operate the shifting switches to check
that the connection has been restored.
20
Front derailleur
FD-7970
Front chainwheel
FC-7900
Rear derailleur
RD-7970
Freehub
FH-7900
Cassette sprocket
length so that it will fit securely into the outer casing holder when
the brake lever is installed.
Junction (A)
Low adjustment bolt
0.5 – 1 mm
< Top adjustment >
Shift the rear derailleur to the smallest sprocket, and then tighten the
top adjustment bolt until it touches the stopper at the position where
the rear derailleur finally stopped. From this position, turn the top
adjustment bolt counterclockwise one turn so that an over-stroke
allowance can always be maintained.
< Battery charge indicator >
Press and hold either shifting switch for 0.5 seconds or more. You can
check the amount of battery charge remaining using the battery
indicator on top of junction (A).
2 mm Allen key
Knurled grooves
Handlebar
Button
Illuminates (red)
CS-7900 (Except for 11-28T)
Battery indicator
Chain
CN-7900
100 %
Caliper brake
BR-7900
50 %
Flashes green (5 times)
25 %
Illuminates red (for 2 seconds)
Tightening torque:
6 - 8 N·m {52 - 69 in. lbs.}
One Holland, Irvine, California 92618, U.S.A. Phone: +1-949-951-5003
Industrieweg 24, 8071 CT Nunspeet, The Netherlands Phone: +31-341-272222
3-77 Oimatsu-cho, Sakai-ku, Sakai-shi, Osaka 590-8577, Japan
* Service Instructions in further languages are available at : http://techdocs.shimano.com
Please note: specifications are subject to change for improvement without notice. (English)
© Apr. 2010 by Shimano Inc. XBC IZM Printed in Japan.
Top adjustment bolt
5 mm Allen key
When installing the components to carbon frame/handle bar
surfaces, verify with the manufacturer of the carbon frame/parts for
their recommendation on tightening torque in order to prevent over
tightening that can cause damage to the carbon material and/or
under tightening that can cause lack of fixing strength for the
components.
Button held down
Illuminates (red)
Approx. 5-second period
Flashes (red)
Protection clear
operation
Protection
cleared
By shifting from the largest sprocket to the
smallest sprocket, the rear derailleur will move
toward the outside by the over-stroke allowance
and then move back.
0%
Illuminates green (for 2 seconds)
Flashes red (5 times)
* When the battery charge is low, first the front derailleur will stop
operating, and then the rear derailleur will stop operating. When the
battery is fully spent, the derailleurs will stop at the positions where
they were last shifted to. If the battery indicator is illuminated red, it
is recommended that you recharge the battery as soon as possible.