Originally Posted by: castellan 
Motor bikes are the same all over the world and Sep is the start of year date.
Now we have 2 dates on Jap cars as well the build date and the compliance date in Australia I think they are called, my build date is May 2015 and the Aus compliance is Aug 2015.
Yeah, I think the Sept release/MY date thing is now becoming very commonplace worldwide.
On the subject of Aussie compliance plates, the time gap between the build date & the compliance date can vary markedly.
On Aust. built cars there is no issue; the 2 dates are usually the same, because they are built & 'complied' in the one factory.
Imported cars are a different 'kettle of fish'. The Aussie compliance plate is fitted by the local importer/distributor on the day it leaves the wharf or bond storage facility. With fast moving cars (Hyundai/Subaru/Toyota etc.) the time delay is often only one month, allowing for shipping schedules. Slow selling cars however can have a much bigger time gap.
I've seen things like mid-80s Alfa Romeos & top end Hondas & Mazdas where they were built in say 1986 & then complied in 1988. That's a lot of down time. Does that make the car an 86, or an 88 'model' ? Many of these cars had no build date mentioned on their tags.
How they 'date' a car in the used car trade has also varied over the years. Way back before compliance plates were introduced (Jan 1970) cars were 'dated' by one of two means. If the build date was known, which quite often wasn't, they would quote (or guess) that date. More commonly they would quote the year of first registration, which was far easier to ascertain. This latter method also often gave the car a handy 'decrease' in age. A car built in in say early 1967 could've sat in dealer's storage for many months & then got registered in say mid-1969 & many would quote the car as being a 1969 model (unless it was a well known model) & get away with it.
Compliance plates put an end to that, or so they thought. Now the used car trade used the compliance plate date, not the build date, because again the earlier compliance date could 'enhance' the car's resale value.
I'm not sure if it's now law or not, but I recently noticed at the car auctions, they would quote both the build & compliance dates for each & every car. You would hear the auctioneer quote a car as being an 06 build, 07 complied vehicle, or similar.
Dr Terry