Here is the original APRILIA spacer which fits your bearing in order to seal with your oil seal and the O-ring. You can fit this spacer on all am6 but also am5 engines.

Shcema de l'entretoise pour moteur am6 pour faire joint d'étanchéité

Mounts on 50cc motorcycles with gearbox equipped with the minarelli am3, am4, am5, am6 euro 1, am6 euro 2 engine:

APRILIA RS 50cc am6 engine from 1997 to 2006 (new attention after 2006 in derbi euro 3 engine)
APRILIA RX am6 engine (attention news after 2006 in derbi euro 3 engine)
APRILIA MX am6 engine (attention news after 2006 in derbi euro 3 engine)
APRILIA TUONO 50cc am6 engine from 1997 to 2006 (new attention after 2006 in derbi euro 3 engine)

BETA RR
BETA RR ALU
BETA CRE
HONDA HM
HONDA CRE
HONDA BAJA
HUSQUVARNA WXE
HUSQUVARNA CH
HM DERAPAGE
HM CRE
MALAGUTI DRAKON
MALAGUTI XTM
MALAGUTI XSM
FANTIC CABALLERO
PEUGEOT XP6
PEUGEOT XPS
MOTORHISPANIA RYZ
PEUGEOT XPS
PEUGEOT XP STREET
PEUGEOT XP STREET EVO
PEUGEOT XR6
MOTORHISPANIA RX
PEUGEOT XR7
MOTORHISPANIA RX-R
RIAJU RS1
RIEJU RS2
RIEJU RS2 MATRIX
RIEJU RS2 MATRIX PRO
RIEJU SMX
RIEJU MRX
RIEJU SPIKE
KEEWAY TX FR
YAMAHA DT
MBK X-LIMIT
YAMAHA TZR
MBK X-POWER
SHERCO SM
SHERCO ENDURO
SHERCO HRD
SHERCO ENDURO
CPI SM
And many other machines!

Kit of clips and washers for TOP PERFORMANCES RACING gearbox for MINARELLI AM6 gearbox (and original 1st series)