chapter 3: Inspection, Adjustment , and Lubrication
Some Trek bicycles are equipped with a derailleur shifting system, which includes the derailleurs, the shifters, and the shift cables. Read the Warning about Mechanical Work before performing any service work on your bicycle.
In these instructions, we refer to shifting terms:
· Up-shifting is changing to a gear that is harder to pedal: a larger chainring or a smaller rear cog.
· Down-shifting is changing to a gear that is easier to pedal: a smaller chainring or a larger rear cog.
A derailleur changes gears by de-railing the chain, pulling it off one cog or sprocket onto another. A bicycle can have only a rear derailleur (Figure 1), or both a rear derailleur and a front derailleur (Figure 2).
Figure 1:
Rear derailleur
Figure 2:
Front derailleur
The derailleurs are controlled by the shifters. There are several different types of shifters on Trek bicycles.
· Shimano STI Dual Control road shifters where both levers shift gears (Figure 3).
· Campagnolo Ergopower shift/brake levers (Figure 4).
· SRAM DoubleTap shift/brake levers (Figure 5)
Figure 3:
Shimano STI shift/brake lever
Figure 4:
Campagnolo Ergopower shift/brake lever
Figure 5:
SRAM DoubleTap shift/brake lever
If your derailleur system is properly adjusted, it is quiet. If an unusual noise follows any shift, you may need to adjust it. After adjustment, if the noise persists or grows louder, stop the bicycle and try to locate the noise. If necessary, ask your Trek dealer to identify and correct any problems.
Once a month check the shift cables for kinks, rust, broken strands, or frayed ends. Also check the housing for loose wire strands, bent ends, cuts, and wear. If you suspect a problem with your shift cables, do not ride your bicycle; follow the instructions to replace a shift cable, or have your Trek dealer service your bicycle.
Once a month check the operation of the left shift levers/front derailleur. When down-shifted, the front derailleur should shift the chain from a larger chainring to a smaller one. When up-shifted, the derailleur should shift the chain from a smaller chainring to a larger one. The chain should not fall off the inner-most or outer-most chainrings at any time. Also check that the shift levers are tightened to the handlebars with the correct torque specifications.
Some front shifters have a ‘tab’ feature, which eliminates chain rub when the chain is on the middle or outer chainring and one of the larger, inner rear cogs. By slightly downshifting the left shift lever, the derailleur should move in slightly, and should no longer touch the chain.
Once a month check the operation of the right shift levers/rear derailleur. When down-shifted, the rear derailleur should shift the chain from a smaller cog to a larger one. When up-shifted, the rear derailleur should shift the chain from a larger cog to a smaller one. After the shift, the rear derailleur should be positioned such that the chain runs smoothly without jumping. The chain should not fall off the inner-most or outer-most cogs at any time.
Standard rear derailleur
Every month, lubricate all pivot points on both the front and rear derailleurs, including the derailleur pulleys on the rear derailleur, with a light chain oil or similar lubrication.
Whenever a cable is replaced, lubricate the cable where it passes through the housing with a light grease.