I am excited to discover the trek I purchased for parts isn't a mid end 510/520 model. After taking it a part I noticed it has Campagnolo drop outs! It has great finish work between the stays and the dropouts. Let me know your thoughts.

I can Not find a serial number but under the bb shell it says F4. seatpost size is 27.0 and the approx. wheel base on this 24 inch frame is 41 inches. My gut says its an old 730 but that was built before my time selling trek in the 80s

Please advise... Thanks

My guess would be a 710 or 730 also. A pic of the whole framset would help. The color doesn't seem to match anything in the extensive listings at Trek Bike Models by Year and Color is it possible this is a repaint. Really great frame I like it.

My guess would be a 710 or 730 also. A pic of the whole framset would help. The color doesn't seem to match anything in the extensive listings at Trek Bike Models by Year and Color is it possible this is a repaint. Really great frame I like it.

Is that an Ishiwata tube decal? If so its a 5xx series, according to this:
The Retrogrouch: Classic Tubes: Tange and Ishiwata

its a amateur repaint. I know it has an ishawata sticker but with campy drops? and look at that braze work around the dropouts.. that's why im thinking 710 or 730..but wouldn't that have a 27.2 seatpost? something doesn't add up.

Not neccesarly a lot of high end older pre mid 80's bikes had 27.0 or 26.8 seatubes when you get into mid 70's or older anything from 24.0 to 28.0 is possible. The 27.0 seatpost just indicates it is a older model.

So far...Looks like it could be an 80 Trek 510....anyone else have an idea?

Yes, it is a hideous repaint. From what I can see the headbadge is held on with double sided tape, which dates it post 1979-80. Further the bike appears to have under BB cable guides so it would be after before 1981 maybe 1982. The Campy dropouts where on the 1980 models 910-930 (Columbus SL tubes), 710-730 (531 tubes) and 510 (Ishwata 022); not on the 1981 models, but show up in the 1982/83 but only the 728/720 (Reynolds 531/531C) came with double eyelets and short point lugs (by 1984 the Campy double eyelets are gone). Since the earlier models (1979-1980) came with the Nikko Sangyo seamless long point Italian cut lugs and your bike having the shorter lugs and the 1983 720 had canti-lever brake bosses, I would say yours is the 1982 728.

Thanks for your input. Why do you think its NOT a 1980 510? I pray its a 728..but wouldn't that 82 renolds bike have a 27.2 post. I did see a pic of a 510 from 1980 and the cable stop on the chainstay was on the TOP..Mine is on the bottom like the 728. hmmmm

Ah. plus this doesn't have any rear rack braze ons on the frame..so cant be a 728...Hmmm

long point lugs too...Plus..just pulled the headbadge to see if its glued or there were some holes covered up..NO holes..so that does make it newer than an 80..

The housing stop on bottom goes with the under-bb cable routing.

I can't see anyone putting an 022 sticker on a bike that was actually Reynolds.

022 isn't as light as 531.

Yes, I changed it a moment after I posted it, but jjhabs was too fast; I also totally missed the rack eyelets. The bike had been resprayed so the sticker was in question and the other stickers do not appear to be correct. Here is a 80ish 510 with different stickers and lugs.https://www.use.com/5fc79b0c9a51fa3f6d08?p=9#photo=9 Also the 510 has over the BB cabling through 1982 and I'm thinking you probably have to go to 1981 to have no downtube shifter bosses.

From the Vintage Trek web site. The headbadge is brass, colored with black paint. This badge was used until 1983. It is attached with screws (as in this picture) until 1980 models (or late 79 brazing dates). During 1980 and 1981 the screws were phased out, being replaced with double-stick foam tape, similar to that that used for automotive trim. After 1981 the headbadges were only fastened with the tape.

I finally found a good picture of the short lugs and indeed your bike does not have them.

Edit; also from the from the Vintage Trek web site; Prior to 1982, derailleur cables on Treks were routed above the bottom bracket. According to the 1982 brochure, on the upper level bikes, Model 728 and above, cables were routed below the bottom bracket. On Model 614 and below cables continued to be routed above the bottom bracket. (Some variations to the brochure configurations have been reported.)

Using the massive (!) knowledge I've built up reading the forum for 2 months, would it be worth getting a proper gauge down the seat tube to see if it's a genuine 27.0, or an undersized 27.2 because it's easier?

27.0 would imply a 753 frame. The Trek 753 frames (170) did not have eyelets.

I'm thinking you meant that 27.4mm would indicate a frame with 753 seat tube(?).

If a 27.2mm seatpost or two don't fit in the frame then it is sized smaller than 27.2mm.

I have at least one example of just about about every size of seatpost on hand, so always use a post as a guage.

I have in a couple of instances used a particular one-size-larger post in a frame whose printed specifications and supplied post both were a smaller size.

Nope. 27.0 was often used in Metric 753. Depended on the size of the frame. My Raleigh Team Pro uses 27.0mm. Imperial 753, which was introduced around 1983, would be 27.2 or 27.4mm. It is more likely the amateur repaint caused a buildup or it is just pinched. So now I am wondering why I even posted the original comment.

Trek didn't use the labeling on the downtube until 83 or 84. I know its a moot point but if it is a 80 the previous owner would have had to change the lettering after the respray.

Have you removed the fork or bb to see if you can find the original color?

I had no idea that Trek built frames with Metric tubing, --gasp...

I am not saying they did. Just that Metric 753 used that size seatpost in some instances. I think the Trek 170 came out in 84 so it could very will have been Imperial 753. Below are notes by Mike Mullett lifted from another forum:

As written by Mike Mullett - :

1) 753 is Metric-diameter tubing (28.0 mm O.D. for the seat and down tubes, 26.0 mm O.D. for the top tube), and was introduced in about 1975. Seat posts for 753 frames are either 27.0 (for small frames) or 26.8 mm (for large frames).

2) 753R and 753T are Imperial (English/Inch) diameter tubing (28.6 mm O.D. for the seat and down tubes, 25.4 mm O.D. for the top tube), and began production in 1983. Seat posts for 753R and 753T are either 27.2 or 27.4 mm.

Of particular interest is the thinner Imperial tubing which takes the 27.4mm seat pin (pillar). Not a lot of people are aware of this. All these tube sets have a part number starting 80*, but Reynolds seem to have lost these specs.

Sorry for the hijack.

IMO and limited with Treks: 27.0 is pretty typical of an Ishiwata (or possibly Tange, but that wouldn't apply here) seat tube. John Thompson has the full knowledge of all things TREK...hope he reads and replies.

Pm John Thompson and he will likely know