Shimano 105 R7100 rear derailleur, shift cable and BR-R7170 brake service

How to tell mechanical 105 from 105 Di2

Shimano groups RD-R7100, ST-R7120 and BR-R7170 as 105 R7100, and RD-R7150 as 105 Di2 R7150. Both use the BR-R7170 caliper.

• RD-R7100 is the mechanical rear derailleur. It has a shift cable clamped to it and a barrel adjuster on the body. It can bolt to a standard hanger or go on a direct mount hanger.
• RD-R7150 is the Di2 rear derailleur. It has no shift cable. Instead it has a charging port with a cover, a function button and an LED on the derailleur. Its battery connects to it by an electric wire.
• ST-R7120 is the mechanical lever. A shift cable comes out from under the bar tape.
• ST-R7170 is the Di2 lever. It is wireless only, runs on coin batteries and has no port for extra shift buttons.

The cassette sprockets are stamped with a tooth count and a letter. On the 11-34T CS-R7101 or CS-R7100 the sequence is 11C, 12E, 13D, 14D, 15D, 17L, 19N, 21R, 24F, 27G, 30E, 34C. On the 11-36T CS-HG710 the last four are 24F, 28F, 32E, 36C. Shimano states the CS-R7100 is compatible with Di2 only.

105 R7100 specifications

Torque figures

On carbon handlebars, Shimano says to check the lever clamp torque with the bar or bike maker.

Install the RD-R7100

Before you start: check the hanger with a hanger alignment tool such as TL-RD11. A bent hanger stops the derailleur shifting properly whatever you adjust.

1. Standard hanger: thread the mounting screw in straight, not at an angle, with the stopper plate sitting against the B-tension stop and no gap. Tighten to 8–10 N·m.

2. Direct mount hanger: remove the B-axle plate, fit the hanger into the direct mount section of the derailleur and fit the B-axle. Tighten to 8–10 N·m.

   From DM-RARD011, installation of the rear derailleur

3. Check now and then that no gap has opened between the stopper plate and the B-tension stop. A gap there causes shifting problems.

Set the high and low limit screws

1. High limit: with the chain on the smallest sprocket, look from behind and turn the high limit screw until the center of the guide pulley lines up with the outer face of the smallest sprocket.

   From DM-RARD011, stroke adjustment (top)

2. Before setting the low limit, tighten the B-screw a little so the guide pulley clears the largest sprocket. With the B-screw too loose the two can hit.

3. Low limit: shift to the largest sprocket and turn the low limit screw until the center of the guide pulley lines up with the center of the largest sprocket.

   From DM-RARD011, stroke adjustment (low)

Check chain length

1. Wrap the chain around the largest chainring and largest sprocket without running it through the derailleur, and bring the ends together at the back of the cassette.

2. Add links for your hanger type. Standard hanger: 2 links, or 3 links in the QUICK-LINK case shown in the manual. UDH hanger: 1 link, or 2 links in the QUICK-LINK case shown.

   From DM-RARD011, checking the chain length

3. With a UDH hanger, check the chain has no slack in any gear. If it does, use the B-screw. Also use the B-screw if the derailleur sits too close to the chainstay.

4. Run the chain on the derailleur body side of the chain retaining plate or pin in the cage. The wrong side can damage the chain or derailleur.

5. Join the chain only with a QUICK-LINK, arrow pointing the way the chain moves when you pedal, seen from the drive side, with both sides fully seated.

   From DM-MACN001, connecting the chain

More on this in how to set chain length.

Set the B-screw gap

1. Shift to the smallest chainring and largest sprocket. If the cage hits a sprocket during the shift, tighten the B-screw until it clears.

2. Set the gap between the tip of the guide pulley and the tip of a tooth on the largest sprocket: 10 mm for 11-34T, 6 mm for 11-36T. Or use the G-pulley setting tool supplied with the derailleur (check the model numbers printed on it) and line the largest sprocket tooth tip up with the line on the tool.

   From DM-RARD011, adjusting the end adjust bolt

3. Shift through all the gears. Redo this if you change to a cassette with different tooth counts. On a UDH hanger, recheck chain slack and chainstay clearance.

Replace the shift cable on an ST-R7120 lever

Before you start: stop the rear wheel turning while you clamp the cable and crimp the end cap, so your fingers stay out of the spokes and chain.

1. Loosen the cable fixing bolt on the derailleur and pull the old cable out.

2. Set the lever to the top (smallest sprocket) position by pushing the release lever until it will not shift further. The ST-R7120 manual says 10 times or more; the RD-R7100 manual says 11 times or more.

3. Fold the bracket cover back from behind. Pry off the cable cover with a screwdriver, feed the new inner cable through the bracket until the cable end seats in the shift unit, then refit the cable cover. Try not to scrape the cable coating.

   From DM-RADBR02, installing the shifting cable

4. Cut the casing with a TL-CT12 at the end away from the printed marking. Remove the cap from the cut piece, open the liner with the TL-CT12 needle (2.2 mm or more), round the end and press the outer cap fully on without damaging its tip. Leave enough length for the bars to turn fully.

5. The derailleur end uses OT-RS900 casing only, with the sealed aluminum cap end at the shifter side. If you need more than 240 mm of casing at the derailleur, use OT-SP41 instead.

6. At the lever, seat the tab on the cap with short tongue in the groove on the lever bracket. Tape the casing to the bar and wrap the bar tape.

7. At the derailleur, back the B-screw out until the stopper plate touches the bracket body with no gap. Size the OT-RS900 by fitting the sealed outer cap temporarily, lining it up with the bottom of the casing holder and leaving enough slack.

8. Clamp the inner cable in the fixing groove. Hold the derailleur still and work the shifter several times to seat everything, then pull the cable taut and tighten the cable fixing bolt to 6–7 N·m.

   From DM-RARD011, securing the inner cable

9. Cut the cable leaving about 30 mm, fit an inner end cap and check it cannot touch the spokes. Then set the indexing.

Grease the cable with SIS SP41 grease if it has been wiped clean. Do not use Premium Grease on shift cables. A polymer-coated cable can look fuzzy as it wears; inside the casing that is only cosmetic.

If the old cable head breaks off inside the lever and will not come out, take the lever off the bar, remove the bracket cover and the unit cover screws at the bottom of the bracket, and pull the stuck end out without touching the spring. Refit the unit cover screws at 0.2–0.25 N·m. Shimano suggests fitting a new SL cable guide at the same time.

Adjust the indexing on RD-R7100

1. Shift to the fifth sprocket from the largest. On a double, use the big chainring.

2. If the chain already rubs the next larger sprocket, turn the barrel adjuster clockwise until it goes quiet.

3. While pedaling, turn the barrel adjuster counterclockwise until the chain just starts to rub the next larger sprocket.

4. Turn the barrel adjuster five clicks clockwise.

   From DM-RARD011, SIS adjustment

5. Shift through every gear while pedaling. If you hear noise, start again from step 1.

For the general method, see how to adjust a rear derailleur.

Replace the pulleys

1. Remove the guide and tension pulley screws and take out the pulleys. The RD-R7100 pulley set is Y3JU98030.

2. Fit the new pulleys with the arrows pointing the way they turn when you pedal forward.

3. Tighten the pulley screws to 2.5–5 N·m.

   From DM-RARD011 and DM-RARD010, replacing the pulleys

Replace pulleys that have enough play to make noise. The same steps and torque apply to the RD-R7150.

Di2 RD-R7150: charging, battery level and gear adjustment

The battery is charged through the port on the derailleur.

Check the battery level

1. Press the function button on the derailleur once, quickly (under 0.5 seconds).

2. Read the LED: solid green is 51–100%, flashing green is 26–50%, red is 1–25%, and off means empty. As the battery runs down, the front derailleur stops first, then the rear. When it is flat, the derailleurs stay in the last gear used.

   From UM-3GK0A, checking the battery level

Charge the battery

1. Charge indoors. Open the charging port cover using the notch and plug in the charging cable. Do not use a USB hub.

2. The LED is solid blue while charging and goes off when charging is done. Allow about 1.5 hours from a USB AC adapter or about 3 hours from a PC.

3. If the LED flashes red, it is a charging error. Use an AC adapter rated over 1.0 A.

4. You cannot shift, adjust or pair while charging, and charging stops if E-TUBE PROJECT is connected. Unplug the cable before you ride.

   From UM-3GK0A, charging method

Check and replace the ST-R7170 lever batteries

1. Hold two shift switches together for 0.5 seconds or longer. Green means 11–100%, red 1–10%, off empty.

2. Replace with CR1632 coin cells, 2 per lever, plus side toward the plus mark. Work somewhere clean and dry and use a blunt, insulated tool. Check the gasket is clean and tighten the holder screw to 0.4 N·m.

   From DM-RADBR10, replacing the dual control lever battery

Set the limit screws on RD-R7150

1. On the largest sprocket, tighten the low limit screw until it just touches the stopper.

2. On the smallest sprocket, tighten the high limit screw until it touches, then back it out one turn.

   From DM-RARD010, adjusting the rear derailleur

Wrong limit settings can make the derailleur shift back after about 5 seconds, cause constant noise, drain the battery fast, damage the motor beyond repair or throw the chain.

Adjust the gears (adjustment mode)

1. Shift to the fifth sprocket from the largest.

2. Hold the derailleur function button for 2–5 seconds until the LED turns solid yellow.

3. While pedaling, press shift switch X to move the derailleur toward the larger sprockets until the chain just touches the fourth sprocket and makes a slight noise. There are 37 positions, 18 each way.

4. Press shift switch Y 5 times.

5. Hold the function button for 0.5 seconds or more to leave adjustment mode, then check every gear.

   From DM-RARD010, adjusting the rear derailleur

After a crash, the derailleur may go into protection mode. To reset it, shift to the largest sprocket and then to the smallest while pedaling.

BR-R7170 brake pads and bleeding

The BR-R7170 caliper, ST-R7120 and ST-R7170 levers use SHIMANO Hydraulic Mineral Oil. Never mix it with SHIMANO Low Viscosity Oil, and never put any other fluid in these brakes.

Oil and pads: pads that have touched oil or grease must be replaced. Clean the rotor and caliper with isopropyl alcohol or a dry cloth, never commercial brake cleaner. Wear eye protection and gloves.

Replace the brake pads

Replace pads when they are contaminated with oil or grease, when the thinnest part is 0.5 mm, or when the pad spring touches the rotor. Replace the rotor at 1.5 mm or less, or if the aluminum layer shows.

1. Remove the wheel. Remove the retaining clip and pad axle and take out the pads. Clean the pistons and the area around them.

2. Fold back the bracket cover. Set the lever so the top of the bleed screw is level, remove the bleed screw and O-ring without dropping them, and screw in the TL-BR002 oil funnel.

3. Push both pistons straight back as far as they go with a flat tool. Do not twist them and never use a sharp tool. Having the funnel fitted while you do this protects the diaphragm in the lever.

4. If the funnel is empty, add oil. Fit the yellow bleed spacer with the pad axle and clip, pump the lever several times, then remove the spacer.

5. Plug the funnel with the oil stopper, remove the funnel and refit the bleed screw and O-ring. Tighten it to 0.5–0.7 N·m with a torque wrench.

6. Fit the pad spring to the new pads (finned pads have L and R marks), slide them in, then fit the pad axle and retaining clip. Tighten the pad axle to 1–1.5 N·m with a torque wrench.

   From DM-RADBR10, replacing brake pads

7. Fit the orange pad spacer and pump the lever until it is firm. Remove the spacer and refit the wheel.

8. Spin the wheel and check the rotor does not rub. If it does, check the wheel is seated properly, then re-center the caliper.

9. Test before riding: squeeze the lever hard. It must be firm and must not pull to the bar. Then bed the pads in on a flat, safe area: accelerate to a moderate speed and brake to walking pace, one brake at a time, at least 20 times per brake. Braking gets stronger as they bed in.

Bleed BR-R7170 with mineral oil

Change the oil when it is noticeably discolored. You need the TL-BR001 syringe and tube and the TL-BR002 funnel, and oil from a clean, sealed bottle.

1. Put the bike level in a stand. Remove the wheel and the pads.

2. Fold back the bracket cover, level the lever bleed screw, remove the bleed screw and O-ring and fit the oil funnel.

3. Push the pistons fully back with a flat tool and fit the yellow bleed spacer with the pad axle and clip. On a rebleed, pump the lever about 10 times to settle the pistons. From here on, do not squeeze the lever while adding oil; if you do, drain and start again.

4. To drain old oil, remove the bleed boss cap and bleed screw cap on the caliper, fit a tube and bag to the bleed boss and open the caliper bleed screw. Pumping the lever speeds it up.

5. Fill the syringe, connect it to the caliper bleed boss, open the bleed screw half a turn and push oil up until the oil in the funnel has no bubbles.

6. Close the bleed screw for now and pump the lever about 10 times.

7. Tilt the lever so the funnel is at the 20° angle shown in the manual. Bleeding at the wrong angle can trap air. Work the lever slowly until no more bubbles come up.

8. Open the bleed screw half a turn and push more oil from the caliper until no bubbles show, then close it. The lever should go loose, then slightly stiff, then stiff. If it does not get stiff, go back to the 20° step.

9. Bring the lever back to level and remove the syringe, with a rag over the tube end.

10. Fit the tube and bag to the bleed boss and open the bleed screw to let oil and bubbles run out. Tapping the lever and caliper gently or shaking the hose helps. Keep the funnel topped up.

11. When no more bubbles come out, tighten the caliper bleed screw to 4–6 N·m with a torque wrench. Remove the tube, wipe the caliper and refit the bleed boss cap.

12. Plug the funnel with the oil stopper, O-ring side down, and remove the funnel over a rag.

13. Refit the lever bleed screw and O-ring so a little oil overflows as it seats, and tighten to 0.5–0.7 N·m. Do not pull the lever before the bleed screw is in. Clean off spilled oil with isopropyl alcohol.

    From DM-RADBR10, mineral oil replacement

14. Fit the pads as in pad replacement, refit the wheel and do the same brake test before riding: firm lever, no rub, then bed in.

Do not overtighten the reach adjustment screw on the lever; Shimano says that can stop the bleed working properly. See also the general guides to bleeding mineral oil brakes and replacing disc brake pads.

Parts and consumables

Tools

• 2 mm, 2.5 mm, 3 mm, 4 mm and 5 mm hex wrenches
• Hexalobular #8 and #10 drivers, cross head screwdriver #2
• Torque wrench (values on this page run from 0.2 N·m to 50 N·m)
• TL-CT12 cable cutter with liner needle
• TL-RD11 hanger alignment tool
• TL-BR001 syringe and tube, TL-BR002 oil funnel and oil stopper
• TL-BH62 hose cutter and insert tool, 8 mm spanner
• TL-CN29 or TL-CN35 chain cutter, TL-CN10 QUICK-LINK tool
• TL-LR10 or TL-LR15 lock ring tool, TL-SR24 sprocket remover

Troubleshooting by symptom

Mechanical shifting cannot be adjusted to run quietly

Check the hanger with TL-RD11, clean and grease the cable, and check the casing is not too long or short. Then redo the indexing.

Shifting has got worse over time

Check for a gap between the stopper plate and B-tension stop and refit as in installation.

Noise from the derailleur cage

Check the pulleys for play and replace them if loose.

Lever squeezed with the wheel out, pads now touching

The pistons have come out too far. Fit the oil funnel and push them back with a flat tool, as in pad replacement.

Pads drag on one side

Push the pistons back, pump the lever with the bleed spacer fitted, refit the pads and check both pistons come out evenly.

Lever feels soft

There is air in the system. Bleed the brake.

Di2 will not shift

Check the battery level and pairing, make sure the charging cable is not connected, and shift once to wake the system if it has been more than 30 minutes since the last shift. Reset protection mode if the bike has been knocked over.

Di2 LED flashes red while charging

Use an AC adapter rated over 1.0 A and do not charge through a USB hub.

Di2 LED solid red

The battery is too low. Charge it.

Derailleur or battery feels warm while charging

About 12°C above room temperature is normal. If it is hotter, unplug it and let it cool.

Related: Shimano Tiagra 4700, Shimano Hollowtech II cranks, Adjust a rear derailleur, Bleed mineral oil brakes, Replace disc brake pads