On my 86, there is a 4 digit number near the serial #. I have read on this forum that the first 3 digits are the day of the year it was made and the last digit is the year but like how do you know if its 86 or 76 if it just ends in 6 ?

Anyway, i think it "might " be safe to assume that the first 2 digits indicate the month of the year the bike was made and the last 2 digits indicate the year ...

take another look and see what you find... On my bike, the last 2 digits are 86 so I assume it was made in 1986.. this same four digit date encoding scheme is used on computer memory chips.