Hey all,

I have an old Raleigh Grand Prix that I'm interested in converting to a fixed gear ride. However, it has a 24.4mm seatpost and I would like to change the post to something a little more conventional. Anyone have an idea where I can get a more modern seatpost in this size? If I have to, I was considering taking a 25.0 post to the local machine shop to have it turned down.

Any help/advice would be appreciated.

If it must stick out an appreciable length, then this isn't a wise thing to do. It may be too weak after removing that much material. Most posts are not that thick in the first place.

If it's not extended much, you'll probably get away with it.

If you must have it quite extended, there's also the idea of turning a 24.4mm stock tube to the desired length, with the top turned down and threaded. Find a large dia. seatpost with an inside dia. sufficient for internal threading. Cut about an inch of post, thread the inside and loctite your 24.4mm tube into it.
It should be very strong.

Thanks for the reply, WNG. This is one option that I didn't consider.

I doubt very much that's the correct size. Raleigh used 25.4 or bigger on pretty much everything; 24.4 was a very uncommon size used on some french bikes. someone probably put the wrong size in at some point and crushed it down. an easy way to spot this is to look at the slot in the back of the seattube; the sides should run parallel. either that, or your calipers are off.