Your search for "monster 821" revealed the following:
CNC RACING | Throttle control tube RBW DUCATI - SPORT
$39.37Throttle tube version SPORT designed to eliminate the slop/play of the throttle control. Machined from solid and made of special plastic...
CNC RACING | Front sprocket 15 Teeth P520 Ducati - Lightened
$28.69Super-lightweight,non-silenced front sprocket 15 teeth pitch 520 for Ducati engines made of 16CrNi4 steel characterized by extremely high surface hardness...
Ducibike ducati GS01 - STEERING HEAD NUT RING
$45.20Anodized billed ergal. Be substituded to the original. Product Application ALL DUCATI MODEL (NO HYPER 1100/ 821 - NO DIAVEL...
MOTOCORSE TITANIUM ALTERNATOR COVER MTS-HYPERM-M1100 /796/ 696/1200/821
$285.00TITANIUM ALTERNATOR COVER MTS-HYPERM-M1100 /796/ 696/1200/821