I'm a regular bike rider around the Wynnum Manly and northern Redlands. I've have the fortunate experience of having magpie attacks all the time over there nesting season. What's this "fortunate"? I wear the correct PPE when on the bike. Bike helmet, protective wrap around safety glasses and finally velco-on-to-the-helmet ear protection flaps (cut out from 3 litre milk bottle).
When they attack, I just remember I'm there for the bike ride and my safety so I do not let go of handle bars or get distracted and not fall off. Happen to a friend who broke two wrists.
Yesterday during ride, four magpie strike attacks, two in Manly, one in Birkdale and Mad Max in King Island Drive Wellington Point. Mad Max just doesn't give up with a record ten strikes in one attack. No injury from falling off bike or strikes. By the way, zip ties on helmets work perfect for 9 months of the year, September to November - useless! Remember, it's what YOU do that counts when they strike, Magpies do what nature tells magpies to do, get over it.