Hello everyone,
Allow me to first state that I've been using this site to glean information for my various projects and it has been more than helpful in so many cases. I want to thank everyone for being so active and helpful, even though I wasn't a member. Now that I am a member I only hope to be as much help to everyone else.

Right, on with my first post.

I have a Puch Pacifica that is a 54cm(Apx) frame. It's one of the Japanese models and I believe the material is 551? steel. I was wondering if anyone knows what the seatpost dia might be. I travel for a living and don't get to spend loads of time at home and I've negelected to take a measurement myself. I've finally decided to build this bike up, as I love it. I need to order parts so that they are waiting for me when I get home. Thanks in advance for any help in this and if anyone has any links to info on this particular bike I'd appreciate it. I'm always one to try and return a favour.

-Arab

How about some photos?

I'm sure someone here has got the links for the seatpost diameters based on the type of steel used...

East Hill

you sure that's not 531? seems odd a japanese model would have 531. Seatpost diameter depends on weather it is double butted or straight gauge. Could be 27.2mm I think 26.8mm for straight gauge if it is 531.

OK, I have a Puch Pacifica out in the garage and it does have the Japanese tubing. It is not Reynolds, I know that for a fact. It may be Ishiwata or Tange, but may also just be "chro-mo" . Its two thirty a.m. and I can't sleep but if I go into the garage now to check I'll wake the family.

I'll check for you tomorrow. The seatpost size is either 25.4mm or 26.4mm, honestly I think its the first one. That's exactly one inch by the way. I have a nice American Classic silver microadjusting post in mine.

Actually, 26.4 for straight gauge (been there ... done that).

Oh man thanks guys!
Aye, I clearly meant 531 not 551 and that was an assumption based upon a decal I had remembered seeing (I thought on this bike.) I've never given this bike too much attention my Ex-girlie used to ride it, but she finally got tired of not being able to reach the ground and bought her own. So now it's back to me and I like the thing so much I'm turning it into a project build. I'm in Toronto at the moment and the bike is in Orlando, so I couldn't get any pics or take the measurement myself. I had assumed it was 531, but I'm certain it's made in Japan as I've read the "Made in japan for PUCH" sticker far too many times. So I'm guessing this is some other material??? Cro-mo??? what??
Honestly though this is going to help loads for my ebaying of parts so the bike will fit me again.
New Post, wheels, cranks (I have the old ones around), etc. You are each a wealth of knowledge and great. ;>

I would not all be surprised if it is high tensile steel. I have one of those "Made For" Puchs that I'm currently using as a fixie commuter. The seatpost diameter on mine is 25.8. It's hi-ten.

Don't know for sure what model it is as the labels were gone before I acquired it, but from photos of Pacificas I've seen, the frames look very similar to mine.

Unfortunately you're going to have to wait until you return to get more specifics about the bike. I's doubtful that it is 531 so we have no idea what size seatpost it'll take.