Checking The Drive Chain Slack - APRILIA pegaso 650 i.e. Service Manual

Pegaso 650 I.E.
 $2)6% #(!).
Carefully read 0.5.1 (PRECAUTIONS AND GENERAL
INFORMATIONS).
For the maintenance intervals, see 2.1.1 (REGULAR
SERVICE INTERVALS CHART) under:
– Final transmission (chain, crown and pinion).
The vehicle is equipped with an endless chain, in which a
ring link joint is not used.
Chain type: see 1.5 (TECHNICAL SPECIFICATIONS).
a
CAUTION
The drive chain is provided with O rings among the
links, in order to keep the grease inside them.
Carry out the adjustment, lubrication, cleaning and
change of the chain with great care.
N
Position the vehicle on the appropriate rear support
stand, see 1.8.1 (POSITIONING THE VEHICLE ON
THE REAR SUPPORT STAND m).
N
Position the gear lever in neutral.
N
Turn the rear wheel slowly by hand.
N
Further, check the chain and sprockets and make sure
that they do not present:
– damaged rollers;
– loose pins;
– dry, rusty, crushed or seized links;
– excessive wear;
– lacking O rings;
– sprocket or teeth excessively worn or damaged.
a
CAUTION
If the chain rollers are damaged, the pins are loose
and/or the O rings are damaged or lacking, it is nec-
essary to change the whole chain unit (both sprock-
ets and chain), see 7.3.2 (REMOVING THE FINAL
DRIVE UNIT).

2.29.1 CHECKING THE DRIVE CHAIN SLACK

To check the slack, proceed as follows:
N
Stop the engine.
N
Position the vehicle on the appropriate rear support
stand, see 1.8.1 (POSITIONING THE VEHICLE ON
THE REAR SUPPORT STAND m).
N
Position the gear lever in neutral.
N
Make sure that the vertical oscillation, in an intermedi-
ate point between pinion and crown in the lower part of
the chain, is included between 35 – 45 mm.
N
Rotate the wheel manually, in such a way as to check
the vertical oscillation of the chain even in other posi-
tions; the slack must be constant in all the wheel rota-
tion phases.
a
CAUTION
If in some positions the slack is higher than in others,
this means that there are crushed or seized links.
To prevent the risk of seizures, lubricate the chain
frequently, see 2.29.4 (DRIVE CHAIN TENSION AND
LUBRICATION).
If the clearance is slack is uniform, but higher than 45 mm
or lower than 35 mm, adjust it, see 2.29.3 (ADJUSTING
THE DRIVING CHAIN).
Release 00/2002-02
SERVICE AND SETTING UP
a
CAUTION
An excessive slackening of the chain may cause
noise or make the chain rattle, with consequent wear
of the shoe and of the chain guide plate.
Incorrect maintenance may cause the untimely wear
of the chain and/or damages to the pinion and/or the
crown.
Carry out the maintenance operations more frequent-
ly if you use the vehicle in difficult conditions or on
dusty and/or muddy roads.
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