I just sent a mail to VN airlines to confirm the transportation fee. Here is their reply:
For the check-in baggage allowance does not include special equipments i.e:bicycle.
For the enquiry of special charge for bicycle:
From Hong Kong to Vietnam i.e:
Bike(include container) weights up to 15kg will charge USD125.
From over 15kg up to 23kg will charge USD150.
From Vietnam To Vietnam i.e:
Bike(include container) weights up to 15kg will charge USD75.
From over 15kg up to 23kg will charge USD100.
From Vietnam to Hong Kong i.e:
Bike(include container) weights up to 15kg will charge USD125.
From over 15kg up to 23kg will charge USD150.
And they insist that the bike must be boxed, I cannot use a bike bag to carry it.
Well, I think I will skip HCMC this time, to buy the time for train trip.. I'll take train from Hanoi to Nha Trang, and ride from South to North back to Hue. Does anyone know if the ride from South to North is possible? Will there be difficulties such as wind direction, etc?