24mm seat post
07-26-18 | 05:45 PM
#1
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24mm seat post
Does anyone make them in lighter al alloy?
The seat post post on the Peugeot I知 building is in rough shape, and I figured I would shave some weight if I were to replace.
Lots of options for other sizes, but I知 not seeing anything smaller than 25mm.
The seat post post on the Peugeot I知 building is in rough shape, and I figured I would shave some weight if I were to replace.
Lots of options for other sizes, but I知 not seeing anything smaller than 25mm.
07-26-18 | 07:49 PM
#2
Bikes are okay, I guess.
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Get an alloy 25.4 or similar and take it to a machine shop to be turned down to 24.0. I've had seatposts and stems done. Worked fine. Start with the smallest diameter you can find so there's more meat left in it when it becomes 24.0. I'd be surprised if it cost you as much as twenty bucks.
07-26-18 | 08:42 PM
#3
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thumpism , 07-26-18 09:49 PMGet an alloy 25.4 or similar and take it to a machine shop to be turned down to 24.0. I've had seatposts and stems done. Worked fine. Start with the smallest diameter you can find so there's more meat left in it when it becomes 24.0. I'd be surprised if it cost you as much as twenty bucks.
07-26-18 | 09:19 PM
#4
Francophile
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Kalloy makes seat posts in 24mm. I have two of them. The problem is, they do not always seem to be available. But keep looking.
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07-26-18 | 10:40 PM
#5
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Does it use a shim? If so, what is the diameter without the shim?
07-27-18 | 12:22 AM
#6
verktyg
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For some unfathomable reason Peugeot used those 24mm seatposts. Is it wrong... or just French?
They also used a shim. Seat tubes would usually take a 25mm to 25.8mm seatpost depending on year and model.
The seat tube can be rounded out, reamed and honed.
Google is your friend... Do some searches on "seatpost", "seat tube" and "verktyg". I've posted details and descriptions on this topic a number of times.
Good luck.
verktyg
They also used a shim. Seat tubes would usually take a 25mm to 25.8mm seatpost depending on year and model.
The seat tube can be rounded out, reamed and honed.
Google is your friend... Do some searches on "seatpost", "seat tube" and "verktyg". I've posted details and descriptions on this topic a number of times.
Good luck.
verktyg
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07-27-18 | 04:27 AM
#7
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verktyg , 07-27-18 02:22 AMFor some unfathomable reason Peugeot used those 24mm seatposts. Is it wrong... or just French?
They also used a shim. Seat tubes would usually take a 25mm to 25.8mm seatpost depending on year and model.
The seat tube can be rounded out, reamed and honed.
Google is your friend... Do some searches on "seatpost", "seat tube" and "verktyg". I've posted details and descriptions on this topic a number of times.
Good luck.
verktyg
Thanks! I値l do the research thing. I searched the forums, but the search function leaves much to be desired.
07-27-18 | 05:34 AM
#8
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Bikes: 1970s Alex Singer, 1960s Peugeot PX 10, 1960s Bertin C37, 1973 Carre Bertin C 37, 1972 Carlton Kermesse, 1981 Peugeot PX 14 Super Competition
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The Yellow Jersey had a run of custom, alloy micro adjust posts in 24 mm done for them. Look about 2/3 of the way down the page for the yellow Peugeot. They aren't cheap but they are, I think, what you are looking for. Verktyg's advice about reaming and honing is excellent and should be done before you install your new post.
The Yellow Jersey had a run of custom, alloy micro adjust posts in 24 mm done for them. Look about 2/3 of the way down the page for the yellow Peugeot. They aren't cheap but they are, I think, what you are looking for. Verktyg's advice about reaming and honing is excellent and should be done before you install your new post.
08-03-18 | 02:03 PM
#9
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Sorry to bring this back from the dead.
In in an effort to save money, I attempted to remove the shim allowing for a larger seat post.
Easier said than done as it appears the shim is braised on. Although I managed to bend it in several places making sure that I値l never be able to insert the old seat post ever again...
My thoughts are reaming the tube, which will hopefully remove the shim in the process. The seat tube wall thickness is 2mm and the shim appears to be 1mm.
Is it a terrible idea to try to ream to 25mm? Or should I just play damage control and try to get back to 24mm if I can.
In in an effort to save money, I attempted to remove the shim allowing for a larger seat post.
Easier said than done as it appears the shim is braised on. Although I managed to bend it in several places making sure that I値l never be able to insert the old seat post ever again...
My thoughts are reaming the tube, which will hopefully remove the shim in the process. The seat tube wall thickness is 2mm and the shim appears to be 1mm.
Is it a terrible idea to try to ream to 25mm? Or should I just play damage control and try to get back to 24mm if I can.
08-03-18 | 02:36 PM
#10
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This is steel, right?
2mm thick is an awfully thick wall, unless that includes a lug (or you're measuring both sides).
If you can ream out a full 1mm (shim thickness), that should bring you to a 26.0 which should be much easier to find
MEASURE CAREFULLY BEFORE CUTTING. Choose your end goals, and target seatpost size.
2mm thick is an awfully thick wall, unless that includes a lug (or you're measuring both sides).
If you can ream out a full 1mm (shim thickness), that should bring you to a 26.0 which should be much easier to find
MEASURE CAREFULLY BEFORE CUTTING. Choose your end goals, and target seatpost size.
08-03-18 | 03:37 PM
#11
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From: Greenville, SC / Asheville, NC
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CliffordK , 08-03-18 04:36 PMThis is steel, right?
2mm thick is an awfully thick wall, unless that includes a lug (or you're measuring both sides).
If you can ream out a full 1mm (shim thickness), that should bring you to a 26.0 which should be much easier to find
MEASURE CAREFULLY BEFORE CUTTING. Choose your end goals, and target seatpost size.
Will a standard adjustable ream bit work with the split at the top of the seat tube?
08-03-18 | 03:42 PM
#12
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From: Greenville, SC / Asheville, NC
Bikes: '74 Raleigh Professional, '73 Raleigh Grand Prix, '84 Nishiki Medalist, '85 Gazelle Champion Mondial AB, '81 Peugeot Course, '79 Univega Gran Rally, '85 Torpado Super Strada
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