Bontrager 283415 Bicycle User Manual


 
3
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Correct maintenance of the crankset and other parts of the drivetrain
will make the shift system work better and pedalling smoother, and
increase the life of the parts. Maintenance includes Inspection, Lubrica-
tion, and Adjustment.

 check that the chain is clean, free
of rust, and properly oiled. A dirty chain can pre-
maturely wear the chainrings. All links of the chain
should pivot smoothly and without squeaking, and
no links of the chain should be deformed.
, a more thorough inspection
is recommended. Check your chain for wear with
a chain wear gauge or a ruler. Each full link of a
new chain measures one inch. If 12 links of your
chain measures 12
1/8
inches or more, it should be
replaced. With good maintenance, a chain usually
lasts 1000 to 1500 miles. A worn chain will cause
the chainrings of your crankset to wear prema-
turely. Replacing the chain takes special tools and
training and should only be done by your dealer.
Tighten the pedals into the crank arms; turn the right pedal clock-
wise, but the left pedal counter-clockwise (Figure 2):
• Pedals: 350-380 lb•in (40.2-42.9 N•m).
Clean the chainrings and inspect them for damage. If any teeth are
bent or broken, have the chainring replaced by your dealer. Note that
a few teeth have a special shape to enhance shifting. Also check the
bottom bracket adjustment, and tighten the crank bolts:
• Crank bolt (Figure 2): 360-415 lb•in (41-47 N•m)
• Chainring bolts (steel): 70-95 lb•in (7.9-10.7 N•m)
• Chainring bolts (aluminum alloy): 72-80 lb•in (8-9 N•m)
Check the bearings of the bottom bracket. Lift the chain from the
chainrings, and rotate the crank so that one of the arms is parallel the
seat tube. Put one hand on the crank arm and one hand on the seat
tube, and attempt to move the crank arm laterally toward and away
from the seat tube. Then spin the cranks. If the crank feels or sounds
loose, or if the motion stops abruptly or you hear a grinding noise
coming from the bearings, the bearings need to be adjusted or replaced.
Inspect the crankset for fatigue or impact damage:
• Dents
• Cracks
• Scratches
• Deformation
• Discoloration
• Noise
Figure 2 Tightening pedals
Maintenance