Sekine Bicycle Database

In an effort to better decode the Sekine serial numbers, I set about collecting as many numbers as I could and organizing them into a database. Why do this? Because the more numbers collected, the more accurate the underlying pattern becomes. As part of the process, I track other things about the bicycles- like decaling and components- because these help inform the bigger picture. Eventually I hope to find out why a certain decal was used one year and not the next- likewise with lugs, paint, and even models.

For the database to be successful, I need a little bit of help from every Sekine owner. I don't post or share the numbers without permission, and the serial is something every owner should have written down anyway.

just barely legible

Start with the serial number. Sekine serial numbers are stamped underneath the bottom bracket, and will follow one of two codes: Code 1 is a letter/number followed by numbers, like Y6 22222, and Code 2 is numbers followed by a letter/number, like 22222 B6. Spaces count. Sometimes the numbers will be hard to read, with either the top or bottom edges cut off by a weak stamp; for example in a particular series the number 8 will look like an X.
Other frame details that are nice to know are if it came with a chrome-tipped fork, if the frame has chromed ends, if it has plain stamped drop outs, what colour it is, and if it has brazed or clamp-on cable guides. Some of the frames also have different lugs, depending on model and year.

Next important is frame marking. A few clear, well-lit photographs really help, but the following details are important:
- Headbadge: is it the CS Jewel, one of the Medialles, or the rarer Maple Leaf?
- Down Tube Decaling: Does it say "World Finest Bicycle Made by Sekine", or 'SEKINE' in art deco lettering, or the modern SEKINE font?
- Seat Tube Decaling: Does it have a made in Japan or Canada sticker, a cro-mo tubing sticker, and which of the seat tube 'crests' does it have?

Would the owner of this beautiful red mixte please contact me?

Finally we get to the components. Component dating can be useful, but is not definitive. Components can always be switched or upgraded, substituted, and the bike could even have been assembled with old parts. The most reliable part stamps seem to be the cranks and stem, but usually Shimano parts (after 1976) have date stamps as well.
- Cranks are easy- look on the back, near the spindle. SR brand cranks will have numbers in a small circle, like (9/6) or (77H). Often hard to read.
- SR stems have a similar date code stamped in a circle, below the 'minimum insertion' line.
- Shimano parts have two letter codes stamped onto the backs, like EJ or FC.
See this website for more information on dating components: Vintage Component Dating

To share your serial number, a photo, a story, or as many other details as you know, please leave a comment, or email me: rod of the flies (AT) yahoo (DOT) ca (no spaces, no spam).

I'd like to add a quick thank-you to a guy who posts online with the user name T-Mar, who inspired this effort. If you're out there, please contact me.