My 610 from 1984. Can't tell what that is "L?"
https://live.staticflickr.com/3886/1...f33f34e_4k.jpgP1000876 on FlickrI
I will be back with a pic of the 760. Current pics don't show enough.

Interesting. Seen both F (Fiorini) and L now. Not sure who the L is for.

Joe Starck maybe?

My '85 410 might be too new for a mark? if it has one it is under the cable guide.
https://cimg1.ibsrv.net/gimg/bikefor...5d120b6593.jpg

My 510 (which is in pretty good shape otherwise) is blown out on the BB and really hard to read, seems like there is a mark, I could catch evidence of an imprint, but couldn't find the angle to see it clearly "P"? "R"?
https://cimg3.ibsrv.net/gimg/bikefor...9173c70b7e.jpg
This one is in the weird Exception category, from Vintage-trek: "Serial numbers for four model 510 frames (with a leading F) have been reported that have similar unexpected year dates. (Our thanks to Rich Ferguson, Fred Gomez, and Chris Tank.) The fourth characters are 2, 3, 4, and 5, there may be more. The frames have the early TREK graphics on the seattube. These frames may be related to the M and N leading serial number bikes in the section above."
One takeaway here is it seems like this links these "F" bikes to the 41X & 61X bikes that have the "death fork"

Here is the best picture I have of the bottom bracket on my 1979 710. It looks like it has a mark to the right of the picture but I can't make it out. I won't be able to visit the bike in person for a few months.

https://cimg7.ibsrv.net/gimg/bikefor...7a07ec4213.jpg

[MENTION=9425]madpogue[/MENTION] - If the 60TSI is rare, then we have one each No mark on this one, 1984 760 needing cosmetic attention.

From the Vintage Trek site:

"Some early and mid 80s bottom brackets were marked with 58TSI or 60TSI. In the early 1980s Tim S. Isaac designed new lugs and a new bottom bracket shell for Trek. The new bottom bracket shell is typically marked with 58TSI (or more rarely, 60TSI). This designation is not part of the serial number but is a model number of the shell. The TSI are Tim's initials. The 58 or 60 refer to the angle between the seattube and the downtube."

https://cimg5.ibsrv.net/gimg/bikefor...0ae55d6fc1.jpg

Just noticed this thread with a bottom bracket photo showing a T on a 710 from the 1979-80 time frame.

https://www.bikeforums.net/classic-v...what-year.html

My '78 930 has no mark. :(

The reason the 60TSI (60°) shells are relatively rare is that they were only used on 60cm and larger frames, which comprised a relatively small fraction of total production.

This is an interesting labeling system but I'm a little perplexed. With the size of Trek's production I doubt that a single person built each frame from start to finish, so what do these letters signify? Is it the person who brazed the lugs? The person who managed the team of builders who made the frame? The person who did the final alignment and inspection?
Brent

I haven't been paying super close attention to the thread, but I had the impression that most of these marks appear on pretty early production (TXxxx models) frames. Might production numbers have been low enough in three early years that a single builder could have been (mostly) responsible for an entire frame?

I have yet to remember to check mine. They might reveal the missing link

Thought I would have checked this one already, but today I found more builder's marks on an 82 Trek 510. This one also has two marks, an A near the rear triangle and what is probably an F on the front of the BB shell.

https://cimg6.ibsrv.net/gimg/bikefor...00e1329055.jpg
https://cimg8.ibsrv.net/gimg/bikefor...b93c209fd5.jpg

Well that makes my Ruby even more of a mystery bike. It's definitely not a 60cm frame:
https://cimg4.ibsrv.net/gimg/bikefor...9d69d41b86.jpg
She measures 22.5" center-to-center, which is 56cm. But her serial number (10910) corresponds to a '82 412 24" (60cm). But this bike has a number of oddities. It's 022 all over, and with an investment cast fork crown. The 412 listing indicates hi-ten fork/stays. It has seat-stay rack braze-ons, which the 412 shouldn't have. Under-the-BB shift cable routing, '83-style. Not a catalog-listed colorway. And the panel letters are separate decals over the panel.

You're right. Except for prototypes and team bikes, frame production was spread over multiple people. There were a couple who were responsible for cutting the frame tubes to length, fitting the lugs and bottom bracket shell, and tacking the main triangle together. Another group brazed the main triangle. Another group built the rear triangle assemblies. Still another built the forks. And still another attached the rear triangles to the main frame. The marks on the bottom bracket shell generally only were those of the person who brazed the main triangle.

Well, here's one brazed by John:

https://cimg0.ibsrv.net/gimg/bikefor...20166325c5.jpg
https://cimg3.ibsrv.net/gimg/bikefor...47d3c11d0d.jpg


Has a B on the back, assuming meaning John did the main triangle and "B" did the rear. Have we seen a B before?

I don't remember who had the "B" stamp. I'll have to think about that for a while.

Very interesting bike. Does this one have its own thread? It caught my eye because I have been also working on an 82 412 in the same size. Mine matches expected catalog specs in all regards. A little sleuthing of catalogs seems to show yours having a lot in common with the 82 510/515 bike. Same colors and also the rack mounts. Catalog says Ishiwata 021, but I wonder if that is a misprint for the more commonly used 022. Of course, there is that pesky serial number thing, but it seems like there are several exceptions at this time. I love my 412 and bet yours is a nice rider.

Back to OP topic, I also have an 83 700 and didn’t see any builders letter or mark on it. I may check that one a bit closer though when I get it in the stand.

Here's the thread I started on it shortly after purchase - https://www.bikeforums.net/classic-v...do-i-have.html . Indeed I presumed it to be a 515 based on the color / braze-ons, until I looked up the serial number. Wow, I've forgotten I've had it almost 6 years now.

And yes, it's a wonderful rider, and special. My late wife bought it for me in 2018. When we met in the '80s I was riding an '82 613, my first "doesn't suck" bike. Stolen in 1990 while on loan to my brother. Fast forward to 2018, she found Ruby early one Saturday morning on craigslist while I was sleeping in, recalled how much I miss that 613, called the guy, and he was at our door by the time I woke up. I'll never sell it.

Same; I have two '88 730s (another "tribute" pair; she bought me one, I bought her one, ca. 1987-89), and couldn't find a maker's stamp on either one. Still worth a second look, as you say.

More date to be hashed out.

Recently stumbled across this:

https://cimg6.ibsrv.net/gimg/bikefor...58f8244fe2.jpg


...and it added a name I wasn't really familiar with: Rick Faultusack. Since JohnDThompson also worked on these bikes, he would probably know best about this info.

Now, I also found this post, corroborating the information that this was a builder back in the day, but it remains a question of if this builder may have chosen an 'R' or an 'F', instead of 'F' being for Fiorini?

Any information/correction to the above is appreciated!

EDIT: The linked post was a response to a member who had an 'R' stamp on their BB shell, which led to the speculation of Rick.

JohnDThompson Since I have had a couple early 80s Treks with an "A" stamp, another forum member pointed out that Mike Appel had started out on his own in 1979.
​​​​​​Did another builder take over the "A"? I have a hard time believing that some main triangles hung around the barn three years before making it out the door. Unless Mike popped in a few times for some brazing work on the side.

There were racks of unsold bikes hanging around in the barn when I was there. You can see them behind Dick Nolan and Mike Appel in the brochure picture on Vintage Trek. They never moved. I never heard the story of why they were there, maybe they finally decided to sell them?

That seems surprising to me, given the exponential growth of Trek in those early years. Seems like they would have had a hard time holding onto stock, especially for two years!

The number of frames I have with an "A" stamp post 79 is down to 1; I realized I was thinking about a different Trek.

But a 1982 Trek 510 with an "A" stamp is still a bit of a puzzle

I was there before any exponential growth. They were super happy to get dealers. I'm not sure why I never asked anyone why those frames were there. I think they came from the days when Dick and Mike were building everything, but that was before my time

I didn't note any marks other than the serial number when I rehabbed my 82 Trek 412 a couple years ago. This thread got me thinking so I had another look. Sure enough there is an "A" stamped on the BB shell close to the chainstays.
https://cimg0.ibsrv.net/gimg/bikefor...5661e936ee.jpg


https://cimg0.ibsrv.net/gimg/bikefor...5f16e2cb46.jpg