2007 Shimano XTR Components
As manufacturers release new groups and components, there are often new features that require new service procedures. This is part of a series of articles discussing the newer component groups available from various manufacturers. See also articles on the SRAM® Rival and Force Service and Installation and the Campagnolo® Ultra-Torque and Record.
The article below will discuss the service and installation features of the following Shimano® XTR components for 2007. The following components are discussed:
The Shimano® XTR FC-M970 crankset system is an external bearing system. The bottom bracket bearings sit outboard of the frame shell and are mounted in bearing cups ("adaptors") . Unlike the Dura-Ace, XT, or other Hollow Tech II systems, the left crank attaches to the spindle with an Octalink® type spline system. A crank bolt presses the crank to the splines and holds it in place. The bearing preload is adjusted with threaded ring called the adjusting nut. The nut will push off of the arm and against the bearing face. A crank cap protects the internal threads of the left arm. The system schematic is seen in figure 1.
Figure 1. XTR crank parts
The bottom bracket bearing cups ("adaptors") install using either the hand wrench such as the Park Tool BBT-9, or with the socket tool BBT-19 and a torque wrench (Figure 2). The recommended torque is 305-435 inch pounds (35-50 Nm) for each side.
Figure 2. Secure cups with BBT-19.
The inner face of the left crank has an external thread for the adjusting nut. Make sure the adjusting nut binder bolt is loose and the nut is snug against crank (Figure 3).
Figure 3. Adjusting nut with binder bolt on left crank.
Push spindle through right cup and out side cup (Figure 4). Grease ends of splines. Use care to align splines of spindle to left crank.
Figure 4. Install crank through bottom bracket bearings.
Grease threads of crank bolt and install. The bolt presses the arm fully on the splines of the spindle. The recommended torque for the crank bolt is 392-479 inch pounds (45-54 Nm), which is a substantial load. A torque wrench is recommended (Figure 5). After securing arm, note arm or adjusting nut does not push against bearing face (Figure 6).
Figure 5. Secure the crank bolt with a torque wrench.
Figure 6. The adjusting nut is snug to the crank before setting bearing preload.
The adjusting nut is then turned against the bearing face to remove play and to stop the arms from moving side to side. It is necessary only to snug the ring against the bearing, do not turn the ring with excessive force. The Shimano TL-FC17 is a tool to help turn the nut (Figure 7). The nut can also be turned by hand (Figure 8). Secure adjusting nut binder bolt (Figure 9).
Figure 7. Shimano TL-FC17 tool.
Figure 8. The adjusting ring can also be turned by hand only.
Figure 9. Secure adjusting nut binder with a 2.5mm hex.
Crank removal requires a special tool available from Shimano, the TL-FC35. This tool has pins on one side, and a left hand thread stud on the opposite side. Begin by removing the threaded crank cap clockwise (Figure 10). The crank cap acts strictly as a thread protector, it does not hold the bolt inside the arm and does not secure the arm.
Figure 10. Shimano TL-FC35 tool for removal of crank.
Do NOT remove the crank bolt after removing the crank cap. Thread the TL-FC35 into the arm by turning counter-clockwise. The crank bolt will act to pull the arm once the TL-FC35 stud is threaded into place. (Figure 11).
Figure 11. Install the TL-FC35.
Snug the stud in place and use an 8mm hex wrench to turn the crank bolt counter-clockwise. Double check the wrench is fully secure into the crank bolt hex fitting. The bolt will back against the stud and pull the arm off the spindle (Figure 12).
Figure 12. Crank removal process. Notice increasing gap between bearing and adjusting nut.
Remove the TL-FC35 from the arm by turning it clockwise. If necessary, use the a screwdriver through the holes of the tool to gain leverage. Re-install the crank cap by turning counter-clockwise using the pins of the TL-FC35.
The inner faces of chainrings are heavy "ramped." These shapes assist the chain in shifting (Figure 13). The front derailleur shoves the chain outward, and the ramps lift the chain upward toward the teeth.
Figure 13. The ramp and shifting peg in action.
The XTR chainrings are held to the mounting arms with chainring bolts that use a 12-point star-shaped fitting. Use the TWS-2 to service these bolts (Figure 13 and 14).
The T-30 fits the outer chainring bolt.
Figure 14. The T-40 fits the inner chainring nuts. The smallest ring uses a chain ring bolt only, and uses the T-30 size.
The rear derailleur is fully serviceable (Figure 16). It can be overhauled to clean and lubricate. It is also possible to change spring tension on the pulley cage.
Figure 16. XTR derailleur.
The pulley bolts are threaded but also include an E-clip as a redundancy (Figure 17). Remove the clip from the pulley bolts before removing unthreading bolts.
Figure 17. Remove E-clip before attempting to unthread pulley bolts.
The pulley wheels use a ball bearing system. Seals can be pryed off using a seal pick. The bearing can be cleaned and lubricated in place. While the upper guide pulley has 1/16-inch ball bearings, it is not necessary to dismantle this unit to "overhaul" it (Figure 18). Again, flush pulley wtih balls in place, dry, and lubricate. Re-install seal cover.
Figure 18. Upper pulley with ball bearings.
The front derailleur includes two sets of shims for securing to seat tubes of 28.6mm, 30.2mm, and 34.0mm (Figure 19).
Figure 19. The thickest shim is for the 28.6mm seat tube.
The front derailleur is capable of being actuated as either a top pull or a bottom pull (Figure 20).
Figure 20. Cable routing for either option.
The XTR group uses the same chain as the nine speed Dura-Ace. The chain must be joined with a special rivet. Additionally, when cutting a new chain, it is best to cut the end of the chain that has the inner plates. Determine the shortest possible length for the chain, then add one-inch (two additional rivets) in length (Figure 21). Cut at this point. Leave the end of the chain with the outer plates for the special rivet.
Figure 21. Cut chain at opposite end of outer plates.
It is recommended to press the pin so the special rivet is the first to contact the lower pulley (Figure 22). This is the left rivet when viewing the chain on the lower section between the crank and rear derailleur.
Figure 22. Pressing the special rivet in the left rivet of the outer plate.
The non-integrated shift levers clamp to the bars and can be rotated for angle. There is an additonal lateral adjustment at the shifting pod. The lever body can move approximately 22mm (7/8") laterally to fine tune the reach for the rider (Figure 23).
Figure 23. Adjust shifting pod left-to-right on shift lever bracket.
The shift cable installs through the shifter from the outboard side. Shift the "index finger" lever to release cable tension. Remove the plastic screw and push cable outward (Figure 24).
Figure 24. Shift lever cover cap is removed with a #2 cross-tipped screwdriver such as the SD-2.
The V-brake integrated brake/shift lever system has a hinged cover. Remove the screw and open the cover (Figure 25). The cable end sits inside a cable end carrier.
Figure 25. Remove screw to open shift cable cover plate.
The cassette cogs are made with shifting ramps that help pull the chain as it move to the next cog (Figure 27).
Figure 27. Chain transioning from 6th position cog inward to the 7th position cog.