Mysterious trek 620 finally restored
 

Looks like a crashed vintage Trek with that fork but the frame may be OK. Still the bike looks a bit abused; what's up with that headtube? Is that tape?

The vintage Trek website is your friend here in ID'ing the bike. With the serial number, you'll be able to ID the bike.

That pin stripe tape on the head tube, the frame is in really shape and I look on the down tube for paint chip. Didn’t see any signs of a crash damage

Assuming that headbadge is original, it's 1981-83 - no screws attaching it to the frame, which were phased out between 1980 and 1981.

Lots of ways to damage a fork that don't hurt the rest of the bike. Or someone just wanted to upgrade to a lighter, softer riding fork. This was clearly a project bike for at least one previous owner.

The headtube tape looks like something an owner did as well.

It is a mongrel. I agree with Kontact that the Litage fork may be evidence of damage. Hope the frame is OK.

The usual damage you'll find on a bike that killed its fork is bumpyness or paint cracks under the top of the downtube. If that area looks and feels smooth, I wouldn't worry too much about it.

There were some 5nn and 6nn bikes that used a problematic stamped fork crown that could crack at the sockets. If this is the case, the anomalous fork may be from a fork issue, rather than collision damage.

The Reynolds 531 decal indicating "butted frame tubes" would be consistent with a 61x, corresponding to what JohnDThompson said. The H Lloyd Cycles Reynolds decal timeline says that decal was used from 1982 on. My 1982 614 has the slightly earlier decal, but since 1982 is a boundary year that doesn't really mean much.

As other have said, the serial number will probably settle everything.

i would start with the S/N and frame details. These bikes are now 35 years old and ANYTHING could have been done to them.

I have an '84 610 that I bought new, and I think this has different rear dropouts, and different seat binder bolt attachment. i think its not a 1984 610.

do you have more complete pics in better light and better focus?

Exactly; flip that baby upside down and read the digits on the bottom bracket. That's your starting point.

It is not an 82 61x because they had the rear derailleur cable housing stop on the top of the chainstay. I am going with 83 640 which came with a Tange Levin headset, 531 CS frame and it came in black. The only thing off is that the 640 came with a red head tube. Is that usually a decal or paint?

I'm not even sure its a 6xx! The Reynolds Sticker could have been added incorrectly.

Hard to see, buy I think the lugs eliminate 1985 and later.

Danbianchi, please measure the chain stay length and read out the serial number.

i guess it goes without saying you can't measure the head, top, and seat tube angles consistently to 0.1 degree?

I think you were right on the money with the year 1983 640, because it did come with campagnolo Gran sport pedals, campy hubs,Cinelli bar and stem. Here a picture of the head tube which I removed the white pin strips and I see red color paint under it.

were you able to get the SN decoded from Vintage trek website?

Haven’t got that far yet, got kind of lazy today

Dan,

There is no arcane secret code here, and it is not a fail for you not to know it. All you need to do is turn the bike upside down, read all the numbers and letters stamped into the bottom of the BB shell, post them all here in this thread, and then one of us here who has a lot of experience with the Trek site (like me) will do all the decoding for you (i.e. open the site and see what it says). We can tell you year, model, any geometry features, original color scheme, size, and original parts list. We can then see if it really is (barring production errors on Trek's end) a 600 series, a tourer, a racing bike of the day, or what.

It's as easy as that.

And if the numbers aren't on the bottom of the BB shell, they're on the seat tube behind the crank- then its an 84 400 series frame.

Good point; there are reasons other than a crash why someone might switch out a fork. And the frame may be fine after a crash (if that's why the fork was switched out) which is why a visual inspection helps.

I suppose we should stop all the silly conjecture until Dan posts the SN.

Then we can resume with the silly conjecture and flights of wild fancy.

I still say it was the shape shifting lizard overlord aliens. Bent the fork with powers of their minds.

Where is the fun in that? Silly conjecture is what gets me through the day.:roflmao2:

Damn it... OK!


So it's refinished, so no paint or decals matter....

got the Trek seat stay caps- 84 and earlier-

no screws in the head badge, 80 and later...

under the BB cable routing, 82/83 and later...

Yep! And this where i thought it would be nice to have the chainstay length, to narrow down between the race bikes (760 for example) and sport tours (i.e 510).

Nice to eliminate the TXs as well.

It's got eyelets on the dropouts- so no x60-