Hong Kong Kowloon to shenzen airport with large bike box?

You can go to the nearby Hong Kong-Macau Ferry Terminal to take a ship to Fuyong Ferry, which is very near the airport.
The ferries are at 08:00 and 15:30. Is your time suitable?

Or as I know, there are some direct buses from many places in Kowloon to SZ airport. If you can tell me which specific place is, I may help you to find a bus nearby you to reach your destination.

I'm gona stay at Paterson Street, Causeway Bay.

Is the ferry close by?

thanks for your help

Yes, it’s very near, about 4km far. And the transportation is quite convenient; you can take the MTR Island Line and the bus 18, 962, or 619x to reach the destination.