[QUOTE=SkyDog75;18799299]Not all of 'em. My 1986 Trek 300 Elance built from Ishiwata EX 4130 tubing uses a 27.0 mm seatpost, too.
The original SR post from that bike, marked by the factory as 27.0, is in my parts bin and available if you need a fallback option. (I had to replace it because the head of the seatpost clamp is a little tall and contacted the underside of the saddle I wanted to use on that bike.)[/QUOTE
Apparently a few did not get sent through the seat tube reaming station. The lit says all vintage Treks beside a few special models were 27.2
appreciate the back up but I'm sure Francophile has me covered!