Sounds like a similar situation as the locking petrol caps. From my experiences, early ones had a three digit code that was different to the ignition key, later ones had a matching four digit code - caps were identical apart from this.

Sounds about right Gruncleal!  I can't find documentation...  I know I had it someplace...  I think the factory key blank numbers were really low like "111" and "112".

"I think the factory key blank numbers were really low like "111" and "112"."

Agreed, Mark.

Unfortunately, the number on my own early locking cap is too faded to read.

If I recall correctly, the format for the key was not in the reference library of locks and codes that my own master locksmith had, so he had to cut a key using his black magic!

Went to look and see if my ignition key was the same as the lock… there isn’t a locking gizmo for the front end… huh..
Sneezles61

I used this man for a key to one of the bikes I had and needed one. His worked fine.

I just drilled mine out and replaced with nice new Yamaha locks that I found on eBay from sellers in Malaysia I think. Yes, 2 keys, but for me not a hassle

When it warms up a bit I will get you some pics and some info. Thanks, D