I’m an NSF only earning $580. How much should I save to afford and sustain a motorbike? (Assuming I cannot be promoted with higher pay)?

Agree with Wen Fong, besides as an NSF, assuming that you have to stay in, you won't be able to ride your motorbike and it'll be parked at the carpark most of the times. Over the weekends, you'll probably want to catch up on your rest.

To be honest, I think trying to buy and sustain a motorbike at this stage is the wrong focus. vehicles are depreciating expenses, and not something you should be aiming for when your income is low. $580 can't even really cover all your expenses, and I think it will be better if you save that money for the future!

Being an NSF, I don't think a motorbike is a necessary expense (even more so if you are a stay-in), and the money could be better spent on educating yourself more on investing, or upgrading your skills for the future.

Why not save a little more, and in the future, when you have a higher income and more savings, then think about luxuries like these?