I'm hesitant about bring this subject up BUT if you say nothing then nothing changes so here goes.
I know this is an American forum but lots of members come from other places and for some reason unknown to me Americans tend to say the year of the bike and not it's model number. They also have a really frustrating habit of not even say what bike it is, look how many titles are listed as stuff like for example " My K1 is poorly, I need a fork ear for a K0" etc, there are LOADS of model called K1 and K0, same as F1 and F2 etc. In the 70s I believe it was a US requirement for bikes to have a VIN plate with year of manufacture, most of the rest of the world didn't get VIN plates, so saying it's a 74 550 means not a lot to anyone not in the USA. Is it a 550K1 or 550K2 or a 550F1/2 etc, there are huge differences between those models, mostly cosmetic I'll admit but it's confusing for us in the UK for example who will always give the model number in full, if we are after a petrol tank for a CB550F2 that's what we will ask for due to the differences in paintwork, fork ears were different between the F1 and F2 as were clocks etc.
We also have CB500K1 bikes sold in 1976 for example, old stock that was slow to move, so referring to a 76 500 on here would probably make members think it's a 500K3 and those are a lot different than a K1.
Just looking for a little clarity that's all.