DATE CODES

[Sgt.Pinback]

Uli, i have made a mistake.  Looking at your tank again, it appears the later version 17 liter.  it's kind of hard to tell in pictures, appears there are wrinkles on the sides, but a closer look, there are no no wrinkles on the side.  My apologies for creating misunderstanding.

Can you see better on this pic?

[kp]

So "4B" can't be February 1969.
As "H" can't be August 1969 and "N" can't be a month anyway.

I suspect you are correct as far as the shocks and tanks are concerned. It's probably a good time to discuss why there are these dates and codes. My own thoughts are that the production of parts, either by the company itself or its sub-contractors, needs to be tracked so that any problem that emerges can be identified as either a design flaw, a production problem or a material issue (bad batch of electrical wire, poor quality steel etc) The company or sub-contractor suppliers may have their own method which we may never decode. Ford and GM had been date coding for decades pre 1970. We need more info on dates and codes from other members. Please

[Steve Swan]

So "4B" can't be February 1969.
As "H" can't be August 1969 and "N" can't be a month anyway.

I suspect you are correct as far as the shocks and tanks are concerned. It's probably a good time to discuss why there are these dates and codes. My own thoughts are that the production of parts, either by the company itself or its sub-contractors, needs to be tracked so that any problem that emerges can be identified as either a design flaw, a production problem or a material issue (bad batch of electrical wire, poor quality steel etc) The company or sub-contractor suppliers may have their own method which we may never decode. Ford and GM had been date coding for decades pre 1970.

We need more info on dates and codes from other members. Please.

i have contacted Keith and Marty, hopefully they will correspond and share what they know.

KP, please pardon me for enlarging and bolding the last sentence of your previous post which i quoted.

[Sgt.Pinback]

Steve, can you please look on the pic above and tell me which version of tank it is?

[Steve Swan]

Steve, can you please look on the pic above and tell me which version of tank it is?

Uli, can you provide a picture of the entire pad the fuel tap screws in to ?  Thanks !

[kmb69]

.....
i have contacted Keith and Marty, hopefully they will correspond and share what they know.
.....

Steve, just sent you a PM. Keith

[markb]

we need to hear from Mark and Bo !

I been watching this thread with great interest. The bikes have been a low priority lately. I hope to get back into it in a month. And #97 is still out in California. After that I will see what I can add to the discussion. It looks like it could last a while.

Mark, when does 97 come back home ?  (on another note, the Supersport runs like a Swiss watch.  could not save that gorgeous tank, i got 30/31 pin holes sealed.......  there's always one  )

It will be there until January. Too bad about that tank.

[cb7504]

KP what codes are you looking for? Marty K.

[Steve Swan]

KP what codes are you looking for? Marty K.

Marty, ultimately, we are hoping to identify every part on a sandcast that has a date code.  KP started the thread and it was our good fortune Uli's bike is apart in the middle of a restoration to see the codes on his parts.  KP has some loose parts, but what we need is a larger sample of parts with date codes so we can contrast and compare similarities and differences not only within and between date codes but also the distinctions we see within and between these parts.  Ideally, what we would like is date codes from what is believed to be factory original Fvin/Evin pairs so we can have dates on parts connected to Fvin/Evin dates, in order to establish a bit of an idea what part one could expect to see on a particular bike with a "matched" vin dates.  

as it stands, we now (and have been for a long long time) referring to parts as "early," "mid," or "late" production run based on the distinctions we've noted within and between various parts directly related -ONLY- to the the part being attached to a particular frame vin.  Having a better understanding of these date codes will help us understand what distinctions we might expect to see on a particular date coded part.

so, that is why i prevailed upon you for your help so we can enlarge our sample.

examples of parts we have found codes on are front brake disc, gas tank, rear brake backing plate, rear shock, rear wheel hub.  There  may be more parts with codes on them.   we also know various engine parts have date codes on them as well, cam cover, sump pan, crank cases, mission cover, head and very likely more as well.

i think we are focused more on identifying as many date coded chassis parts as we can and what those codes are so we can have a range of codes to examine and discuss while looking for consistency and discrepancy.

hope this all makes sense and if you've any more questions, please let us know.

Marty, we really appreciate your help and look forward to what you discover.

Please anyone, feel free to add to the rationale on the value of learning more about these date codes.

[mb124]

Hi all,

I pulled the wrinkle tanks of my bikes and had a closer look at the date stamps .

- 4/3 , type 2 tank off Ebay
- 4/9 , type 3 tank off Ebay
- 4 1.01 , type 3 tank off Ebay
- 4 B /24 , type 3 tank , came with VIN 5120 , German sandcast
- 4 C /11 , type 3 tank , came off VIN 187XX , German diecast , 12/69-1/70
- 4 .815 , type 3 tank off Ebay

My theory is that the date stamps are all correct , but for the stamped bracket only .I.e , the brackets where made up early and date stamped( by a subcontractor?) .
When Honda started to weld together the tanks , the date stamped brackets were fitted more or less randomly .

If anyone has a type 2 tank ( wrinkles in the sides of the "U" , more pronounced tap mount ) with a date stamp later than 4/9 , it should prove this theory . I think 4=1969 , C=March .

Greetings from Norway

Geir