The public ferry may take your own bike to the island for 100k both ways, but it is often more convenient to rent a motobike in nearly every homestay and restaurant on Cham Islands. Costs will be 150-200k plus gas. Be aware to check brakes and lights before you go.
In case you have some trouble going around the island, please call the
english/vietnamese helpline 07795 07797
with your smartphone. Please take a picture of the place you are with your smartphone. The helpline will then notify your homestay and send help to your place. This service is free for you.
The best time to drive is the early morning to see the sunrise over the east vietnam sea in direction Hoang Sa archipelago and the monkey feeding in Bai Huong. Or the late afternoon to see the sunset over Danang. Simply stay over night.