smontanaro 

I already posted this to CR. My apologies if you've already seen this and thought it was a dumb idea... I was reminded of it again when I saw the thread here about a Centurion serial number database.

> It is my understanding that the Atala serial number syntax is fairly
> direct...two digit year, letter (possibly month?) then sequence
> numbers.

Which reminds me of something David White, Bob Troy and I were talking about this weekend after our ride. I think it would be useful to provide a very generic serial number database on the net so that people can collect enough serial number information -- especially for more obscure manufacturers -- to attempt to decode them. Where decoding is impossible or there is no encoding, knowing dates of manufacture would help people date their own frames.

You could submit information (manufacturer, model, serial number, year, confidence in the year, what else?) or query by manufacturer. Obviously, users could browse or query the database as well (CSV download?) I was thinking that you could also submit your email address (not publicized, not included in query results) to be notified of updates to the database.

I can put something simple together on my website as an experiment. If it proves useful, maybe I could get velobase to take it over and give it a more permanent/suitable location on the net.

Skip Montanaro

rhm

I think it's a good idea, but incredibly complicated. I have gathered all the serial numbers I could find for, for example, Normans. And I learned, in the process, almost nothing. I am sure there would have come a point where enough data would be accumulated that the pattern would start to make sense; but I never got there.

Aside from the serial number and whatever you know about the bike (brand name, maker's name, model, model year, and...?), the database should have fields for component dates, location of serial number on frame, location of serial number on fork, and any identifiable maker's marks on frame components (dropouts, lugs, etc).

In most cases many fields would remain blank, but where data is available it should be possible to enter it.

repechage

Bicycles have no ID# convention. Automobiles have national and even international basic forms.
A serial number can be of some help if you know or suspect a brand, even then there are exceptions.

Here is one example, worth a read

https://www.bhovey.com/Masi/masidates.htm

smontanaro 

Thanks for the replies. I realize there is no standard, and am well aware of Bob Hovey's Masi serial number deciphering (I used it when researching the Masi I bought recently). rhm gathered a number of Norman serial numbers but was unable to see a pattern. By making this information public my hope was to allow other people to take a crack at the problem. (Or maybe there's someone else out there with a few more Norman numbers to contribute.)

Thanks for the suggested extensions to the number of fields. I don't want to wind up with an explosion in the number of possible attributes though. After a few (type of fork crown, presence of chroming on dropouts any stays, location of serial number, etc), I suspect it might be best just to toss other variations into a comment field. (I will always be able to add more later, if necessary.) I suspect a URL field might be useful. That way the submitter could refer to the specific bike's photos on Flickr, Picasa, or other photo blog sites.

S

repechage

A noble but hopeless cause.

smontanaro 

Hopeless, why? I'm not trying to actually decode serial numbers, just make a place where they can be aggregated, thus giving others a better shot at either decoding serial numbers for a particular manufacturer or dating their own bike.

S

rhm

The serial number itself could be made into a hotlink to such photos, if available.

But you are right, of course, about the number of fields. One field for "date" should be enough; a second one for comments just about the date (whether it's a guess, or based on a component date, date of purchase, or whatever) would be good but is not really necessary. The best way around that type of problem, I think, is to have both fields but to have two user interfaces, one with only the important fields, the other with everything. Location of the serial number is very important and should be, I think, chosen from a list (pull down menu or whatever) to assure uniform data entry. There should be two such fields, one for frame and one for fork.

What fields do you consider necessary?

I would suggest:

serial number
serial number location (frame)
serial number location (fork)
marque
country of origin (to distinguish English Hercules bikes from German ones, for example)
date
remarks regarding date
bottom bracket threading
identifiable frame components (i.e. Campy dropouts, Cinelli BB, etc)
general remarks (lugged or fillet brazed, step through style frame, etc)