Would this seat post fit an old road bike?
 

I am looking at a seat post on Ebay that I hope would fit my 1988 Raleigh Super Grand Prix.
http://cgi.ebay.com/Seat-Post-25-4-x...QQcmdZViewItem

I do believe my Raleigh has a 1 inch seat post now, as best as I can measure. This posting on ebay claims it is a 1 inch post. Does anyone know for sure if my Raleigh is indeed a 1 inch or 25.4mm? Do you think this seat post on ebay will fit?

Thanks!
Digger

You haven't given any information, aside from saying the bike's a raleigh... it could be anywhere from 25.4 to 27.2 with that info. sheldon brown does have an ongoing seatpost size database you could check.

If "as best as I can measure" isn't with a caliper, then don't bother. Seatposts come in a range of sizes, many of them .2 MM apart. And that .2 MM, as far as your frame is concerned, matters. Many bike shops have a seat tube size checker. It's a tool that is machined in steps matching common seatpost sizes...kinda like what jewelers use to measure the size of rings.

http://www.biketoolsetc.com/index.cg...&item_id=SN-SR

Oh, and I'd bet a dollar that your frame doesn't take a 25.4

Yeah, ok, THAT's the kind of response I am looking for. I know that there are differant size seat posts and I was hoping that, given the year and make of the frame someone may know off-hand. You're right though, it pays to be cautious.

Thanks!
Digger

1"=25.4mm, but there are a lot of different seatpost diameters out there. anmd a 25.4mm won't work in a 25.6mm seat tube without a shim. Even with a shim it might not be as stable. it's amazing how much difference .2mm make.

In other words. try to be sure what size you need before you buy. You'll be a lot hapier with the correct size seatpost. <-voice of experience

Sheldon has a seatpost database on his site somewhere you might find the info you seek there.