The Honda Parts manual tells us that the first K1 frame was 44650 and the first K1 engine was 44806. That tells me that your bike is likely a very very early K1. Keep in mind that there are examples of transition bikes that had a bit of a mix of parts between the K0 and the K1. Can you post pics of your bike?

I agree with KP. Though I dont know your plans for the bike, you will get the most value and the most protection with proper paint.

The short answer is that those codes were relevant in 1969 when the engine was being built, but are not relevant now after many miles and years.

You need to use green plastigauge and figure out what bearings will give you the proper clearances. The place to start is usually green if you are unsure of what you have now.

You MUST get a shop manual. NOT an aftermarket manual. Only the original Honda manual (green cover) will do!

Good luck!

Good point. I will add it shortly.

Im seeing it as available. Im able to add it to my cart and pay for it! ¯\_(ツ)_/¯

Love it. I have an original paint daily driver sandcast...happy to know there is another lunatic out there!

Ah, gotcha. Thanks Kp!

Original round oil filters are very hard to find. Many people take a later cover and turn it down on a lathe. Yamiya sells a replica. It is a bit beefier than the original:

https://www.yamiya750.com/index.php?main_page=product_info&cPath=246_21_250_62&products_id=88

If you get a that yamiya replica, i suggest turning it down on a lathe to match an original.