Ducati 749S 2002 Manuel D'utilisation Et Entretien page 154

Chain tension inspection
Important
Have the drive chain tensioned up at a Ducati
Dealer or Authorized Workshop.
With the motorcycle on the side stand, use your finger to
press down the chain lower section. Then release and
measure distance between surface (A) and pivot centre
below. The reading should be 30-35 mm.
E
Warning
Correct tightening of the tensioner lock nuts (1) is
essential to rider and pillion passenger's safety.
Important
Improper chain tension will lead to early wear of
transmission parts.
Chain lubrication
The chain fitted on your motorcycle has O-rings that keep
dirt out of and lubricant inside the sliding parts. The seals
might be irreparably damaged if the chain is cleaned
using any solvent other than those specific for O-ring
chains or washed using steam or water jets. After
cleaning, blow the chain dry or dry it using absorbent
material and lubricate with SHELL Advance Chain or
Advance Teflon Chain on each link.
64
(fig. 65) Important
Using non-specific lubricants may lead to severe
damage to chain, front and rear sprocket.
30 ÷ 35 mm
1
A
fig. 65