Getting a motorcycle into Singapore

Here are the steps required to get a motorcycle from Australia into Singapore under a Carnet de Passage (all prices in Australian dollars unless otherwise specified):

1. Make sure your bike is registered in Australia and you have a valid motorcycle license to ride it.
2. Contact your local Automobile Association to arrange an international carnet (motor-vehicle passport) and International Driver's Permit (IDP). For me this is RACQ after a discussion with the Australian Automobile Association. The IDP costs about $50 while the Carnet depends on where the vehicle is being taken. In my case, the Carnet cost $950.
3. Organise a provider to fly the vehicle into Singapore International Airport. My provider is QANTAS and they have been very helpful. The current quote for the service is approximately $1600, but final dimensions and weight will resolve this price. (Final mass is 244kg; Final dimensions are 228cm x 71 cm x 130cm; Final price is $1700 based on volumetric mass).
4. Organise for the motorcycle to be "safed" before transport as a dangerous good. This involved removing the battery terminals and taping over them, and removing much of the fuel and oil from the bike. The guys at TeamMoto Enoggera were extrememly helpful in doing this for me. Getting a flush certificate, which tells the transporter what you have done to the motorcycle to make it safe, might also help although in my case it was not mandatory.
5. Arrange for the motorcycle to be crated and delivered to the airport dangerous goods service provider, usually several days before departure. Again, the TeamMoto guys helped with this with a combined cost of $350. Direct Couriers were the dangerous goods and carnet management team.
6. Organise (or have as part of your transit agreement) transit insurance for the motorcycle while it is travelling. HWA Insurance were able to help me with this for $450, but make sure it is for the mode of transport that you are using, either air or sea freight.
7. Organise for a customs clearance and transport agent in Singapore to assist in clearance of the motorcycle through Singapore Customs and delivery to someone who will un-crate the bike. I used Jupiter Air (Singapore) with a quote of about SGD $400 for the complete service. 
8. Contact a Singaporean motorcycle shop to uncrate and re-assemble the bike at the other end. Performance Motors Limited (PML) BMW Motorrad shop can do this with an estimated cost of SGD $250-300. Alternatives for PML BMW include Ram Racing, which I used because they were much more responsive and they were recommended to me. Note that PML BMW Motorrad does not crate bikes up, so if you need to get it back, you will need to organise a different supplier to crate the bike for return to Australia.

Once all this is done, you have a motorcycle ready for riding in Singapore, and ready to take across the border north. There is still more to do to ensure you are legal to ride on the road, but this is the first step, getting a motorcycle into Singapore from Australia.

Some warnings that might help you out. Be wary that departure times and arrival times for the motorcycle might change with outgoing and incoming customs, changes to flights, and additional timing delays for pick up and transport to and from the airport itself. My bike has been delayed at least a week due to outbound customs holding the vehicle up.