z1 dating evidence - 1973 z1a

[alibaba]

help, ive got a 1973 z1a, imported from rhode island i know its sept 73 cos its got a factory production sticker on the headstock,all the datecodes say 73.engine and frame have z1a numbers.unfortunatly dvla have it as 74. does the owners club have access to factory dating records or can anyone help out

[Davy Doherty]

Excatly what do you need to know? 73=Z1.. 74=Z1A..75=Z1B It sounds like you have 74 Z1A although the head stock says 73 its probably an early Z1A so the date codes should all be before the procudtion date hence the 73 date codes it sounds like your bike is correct?check out z1enterprises.com click on the references part and you will get number info there..

[Garn 1]

Davy, as you are aware, it is always a source of confusion.
The Z1 was first produced in mid '72 thru to mid 73.
the Z1A was produced from mid 73 thru to mid 74.
the Z1B was produced from mid 74 to mid 75.
the Z900A4 was produced fron mid 75 to mid 76.
For Alibaba
You can see from above, it is possible to have a Z1A with a 1973 compliance plate/ sticker.
There are two easily seen markings on the frame components you can check, understanding they could have been changed during the life of the machine.
1. Swingarm, top-side within 100 mm from grease nipple there is date code.
2. Brake torque rod (facing inside, centre) date code.

The date code in the above positions are year/ month or vice-versa? eg. A swing-arm off a Z1A produced on the 10th month '73 would have 310 stamped on it, same with torque rod. They are usually within a month of each other.

USA do not recognise these variations in year of production, hence, do not recognise a '72 "Jaffa", only a 73.
Incidently a 10th month 1973 Z1A would have a frame number around Z1E-25000, with the corresponding engine number around Z1E- 25150.
RegardZ

[steve f]

post up the frame and engine number and i can tell what model it is

z1a frame no started at z1f-020001 to 047500
z1a engine no started at z1f-020001 to 047500

[Jerry]

The club can supply a DVLA-friendly dating letter to confirm the age of the bike, FOC to members. I'm surprised the other members on the site didn't tell you, seeing as that was the question you asked in the first place!

[DogsbolloxofZ1B]

Not sure where your getting this info wrt datings of Z1's, the first Z1's were being tested in USA on 26th Sep 1972 (I have the press cuttings) so really the earliest a dealer would have been selling them is Oct '72.
I have ALL of the press cuttings from 1972 - 1976 relating to Z1's - Z900's if anyone wants to see them & has a day or so on their hands pop around.. LOL

[Davy Doherty]

i don't think there is any argument Z1's were on sale/sold in 72 and considered 72's but i would have thought Alibaba's bike would be 74-Z1A saying as he says its got both Z1E/Z1F numbers relating to Z1A be a shame to try and badge it as anything else