Shimano SM-CD800 Dealer's Manual page 12

INSTALLATION/REMOVAL
ISCG type
6.
Adjust the position of the guide and chain.
• Move the bracket left and right from the right side of the crank and align the position
of the top of the chain with the groove on the inside surface of the guide.
• There are two grooves on the inside surface of the guide. Align the upper edge of the
chain with the lower groove for bicycles with rear suspension or with the upper groove
for hardtails.
Groove
(for the hardtails)
Groove
(for bicycles with rear suspension)
Top of the chain
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