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Parking brake adjustment is a 2 stage procedure.
Adjustment at top for cable length and to get correct number of 'clicks' on set mechanism. Standard number is 3 to 5, in the SM.
And second, at the bottom, to set the gap/pressure for the pads when the cable is moving the brake arm on caliper the correct distance.
To check cable adjustment, pull handle to get ONE click.
Measure length between brake arm and cable stay at the park brake caliper.
Standard length is 42.0 - 44.0 mm (1.65 - 1.73 in)
If it needs adjusting, it's the adjuster behind the left engine cover.
Once the cable is adjusted the caliper can be adjusted.
With the rear wheel off the ground, unlock the parking brake.
Then pull the lever til the first click/notch.
Turn wheel by hand and turn adjusting bolt til there is slight drag.
Hold bolt and tighten lock nut (17.2Nm. 13 lbf-ft)
Unlock brake and be sure it turns freely.
Pull the parking brake and count clicks until it locks. (standard is 3-5)
If it is out of standard, re-adjust.