Dumb question:

I just took delivery of what, per Vintage Trek using the serial number database, is a 610 frame (a beauty, by the way ... pics when it's built up ...) built in very late 1980. Since the 61X series didn't show up until the 1981 catalogue, I assume this bike was shipped and sold in 1981, and that would be its model year.

The question is this: the 1981 catalogue shows a 613, 614, and 616, with no separate 610. I'm pretty sure that this means that the 610 frame was the base for those three models, with the difference being how they were equipped (SunTour VX-GT etc. on the 613, up to Shimano 600EX in the case of the 616). That, in turn, means that while I have a 610 frame, I have no way of knowing which of the three models it may have been during its "first" life.

Trekkies: have I got all of that pretty much right, and if not, what have I screwed up? Thanks.

I take it you can't go by the color it is painted?

Apparently not. It's a solid sparkle grey which Trek called "pewter" I think, and per the web site:

"The early bikes, from 1976 to 1981, were available in numerous colors. For these, color is not indicative of model. If color is not given for an 82 and newer model, it maybe available in the brochure for that year."

Some years they used the generic XX0 numbering for the frames in the factory...and they became whatever parts mix and marketing decided later. A few years they seem to be more rigorous, and a few years they practically threw the convention out (as in TX900, 930, 959, and 979). If you are looking for an authentic rebuild, just make it whichever you like best. There's currently no way of proving or disproving anything.

Here's a link to my Trek 6xx of the same vintage presently up on eBay; the serial number says it was made in 1977 but the components beg to differ.

https://cgi.ebay.com/ws/eBayISAPI.dll...MESE:IT&ih=019

Just curious what your serial number is?

My # is 000804 .... everything fits with the other info on the database as to size, tubing, crown forks, drops, etc.

And I'm not worrying about an accurate build. I'm thinking of using a full Exage 500EX 7-speed SIS group, and wheels I've got based on Superbe hubs. My apologies to the purists!

Don't worry about purists, just ride it and enjoy. At present, my Trek 460 (which is verging on being my favorite rider) is a combination of: Shimano 600 headset, SunTour Power Shifter levers, Alpha 5000 front and rear derailleurs, Gipiemme sidepulls, Sugino crank, and Mailliard Helicomatic hubs with Mavic GP4 tubular rims.

Every time I settled on a theme to build the bike, something got in the way. I currently love the mish-mash of parts I've got on it, and will probably keep it that way, although I'd love to someday replace the headset and crank with Gipiemme.

Yep, what Syke said. Do what makes you feel right and ride it. Here's a shot of a Trek 500 frame I picked up on fleabay--needed a tiny bit of straightening on the seatstays courtesy of my lbs--and built up with parts from my collection, the wheels and drive train purchased from BF members. Campy Victory Strada tubulars laced to Campy hubs, Shimano 600 Arabesque ders, 600 cranks and chainwheels, Dura-Ace BB, some Modolo Speedy brakes and levers, Nitto noodle bars with a Cinelli stem, some of my favorite Benotto Cello bar wrap with Velox bar-end plugs, and a well-used Brooks saddle and Sugino seat post. The headset did come with the frame and fork...

Every complete bike Trek built until '79 or so was built to order -- even the 300 series. You can see the racks of completed frames in the famous picture of Mike Appel and Dick Nolan in the early brochures. Framebuilders would build batches of 20, 30, 50 identical frames. But when a bike was sold, we would pick the frame and it would get any braze-ons and then painted and assembled. It was always my impression that some of those frames sat on that rack for longer than they should have because of the way they were built in batches. So that's why a bike may have been sold much later than you would expect from its serial number.

Fun times.