Can you use your car battery to charge the bike's battery?

So basically my bike hasn't been started in yonks and obviously the battery doesn't have enough juice to start it now... God knows where my battery charger is so I was thinking of using the jumper cables and leaving it connected to the car for say 15min (?) without even starting the car.

Google searches seem to think it's fine but I'd prefer to hear from you peeps. Anyone ever done that??

Cheers.