The XBR handbook says very little about choice of oil.
Grade: no specific grade is recommended. the temperature chart shows that above 0C, the following are all suitable: 10W30, 10W40, 15W40, 15W50, 20W40, 20W50.
Service standard: meet or exceed SE or SF. I presume that SG exceeds SF, so is OK.
No mention of semi synthetic or mineral: so both are OK
No mention of absence of friction modifiers or bike specific oil: Car oil seems to be OK.