Seat Post binder problem...

[oldguy00]

I have a steel frame that has the type of binder setup that uses the Campy style binder bolts (2 piece).
The frame takes a 27.0 seat post. I've tried 27.2, and its too big, and a mechanic has measured it at 27.

Problem is, I have a Ritchie 27 seatpost (and it has been measured), b ut I can't get it to tighten into the frame without snapping the binder bolt. I start to tighten it, and I watch the two pieces of the seat lug start to curve together and bend the bolt. If I stop tightening before the bolt is ready to snap, then the seatpost doesn't stay still. What is wrong here?? I've broken about 5 bolts and am gettin frustrated!!

[pale scotsman]

Sure it's not a 26.8? How easy does the 27.0 insert into the frame? Any play, does it just drop in?

[David Kirk]

I have a steel frame that has the type of binder setup that uses the Campy style binder bolts (2 piece).
The frame takes a 27.0 seat post. I've tried 27.2, and its too big, and a mechanic has measured it at 27.

Problem is, I have a Ritchie 27 seatpost (and it has been measured), b ut I can't get it to tighten into the frame without snapping the binder bolt. I start to tighten it, and I watch the two pieces of the seat lug start to curve together and bend the bolt. If I stop tightening before the bolt is ready to snap, then the seatpost doesn't stay still. What is wrong here?? I've broken about 5 bolts and am gettin frustrated!!

Can youtake a photo close up of that area?

Dave

[davep]

Sounds like the post is too small. I had a shop measure a bike for a seatpost and bought what they said - 26.8mm. After pounding the thing down into the seattube I bought a 26.6 and it fit fine.

[oldguy00]

Can youtake a photo close up of that area?

Dave


I'll try to tomorrow, thanks.
Regarding the post being too small......yes, it sounds like it.....but the post is measured with calipers at 27.0. And if I try to put a 27.2 into the frame, it won't go...