Campagnolo 2-bolt seatpost - bolt dimensions?
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Campagnolo 2-bolt seatpost - bolt dimensions?
I just purchased the Campagnolo 2-bolt seatpost pictured below. It should arrive in about a week. Does anyone know the dimensions of the 2 bolts? My guess is they are M8 x 1.25mm, perhaps 30 - 40 mm long. If you happen to have such a post sitting around on your workbench, please let me know. Thanks in-advance.
I ask because all my current saddles have an open slot running down the middle. So I'm thinking of replacing the bolts with hex (Allen) head screws, and adjusting from above. I want to have a few screws on hand when my new seatpost is delivered. Otherwise I'll have to heat & bend an old wrench, or buy an expensive Campy wrench to fit.
In the mail...


Expensive plan B:
I ask because all my current saddles have an open slot running down the middle. So I'm thinking of replacing the bolts with hex (Allen) head screws, and adjusting from above. I want to have a few screws on hand when my new seatpost is delivered. Otherwise I'll have to heat & bend an old wrench, or buy an expensive Campy wrench to fit.
In the mail...


Expensive plan B:

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Most of the bikes I use Campy two bolt seatposts on have modern plastic saddles and a standard 10mm wrench fits under the saddle with good access to the bolts. For the ones that don't I use this:

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FWIW, I always found the Campy bent wrench to be at best a marginal improvement over a regular wrench. It is decidedly inferior to Andy_K's solution.
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I find that once you loosen one bolt. the other will be loose, too. So, I use a regular combination wrench to loose the one at the rear, then make an adjustment either way on the other bolt, with my fingers, then tighten the rear bolt back up. pretty easy, really. This is with a Brooks saddle, though, some others may be more difficult.
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...I think maybe the question here is the length and thread pitch, so they can be replaced with socket head screws.
I don't have one handy, and I do not know the answer, but I have used them with cutout saddles before.
Even if you don't replace them, a 10mm socket, with a small extension and a ratchet did the trick in my case.
...I think maybe the question here is the length and thread pitch, so they can be replaced with socket head screws.
I don't have one handy, and I do not know the answer, but I have used them with cutout saddles before.
Even if you don't replace them, a 10mm socket, with a small extension and a ratchet did the trick in my case.
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I don't use a wrench on the front bolt; I use my fingers. I use a ratcheting 10 mm wrench on the rear bolt. I found it on the road. Actually, I found two ratcheting 10 mm wrenches on the road, but I didn't pick up the second one, because the first works perfectly. So it's just trial and error to get the saddle level perfect. If it's tilted up a little too much, I back off the rear bolt, use my fingers on the front bolt to tighten it down, then retighten the rear bolt with the wrench. Once you get it perfect, there's no need to "screw" with it anymore ... unless you just like messing with the 10 mm ratcheting wrench that you found on the road.
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Why don't you just measure what you have. Thread gauges and digital calipers are cheap and I'd recommend them as part of any cyclists toolbox.
BTW, I love those two bolt posts. So much easier to micro-adjust.
BTW, I love those two bolt posts. So much easier to micro-adjust.
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Any 10 mm offset wrench will do, no need for the expensive Campy wrench.
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I don't use a wrench on the front bolt; I use my fingers. I use a ratcheting 10 mm wrench on the rear bolt. I found it on the road. Actually, I found two ratcheting 10 mm wrenches on the road, but I didn't pick up the second one, because the first works perfectly. So it's just trial and error to get the saddle level perfect. If it's tilted up a little too much, I back off the rear bolt, use my fingers on the front bolt to tighten it down, then retighten the rear bolt with the wrench. Once you get it perfect, there's no need to "screw" with it anymore ... unless you just like messing with the 10 mm ratcheting wrench that you found on the road.



Thanks oneclick, what an odd an odd size. Yes, it is unlikely I'll find it at the local hardware store. Perhaps I'll get lucky and happen upon the ratcheting 10mm wrench that SurferRosa didn't pick up! I have a non-bending ratcheting 10mm wrench, not the one Andy_K recommends. Using the advice of others, it looks like the way to go. Thanks y'all

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But the one you already have is just like it and works fine ... on the rear bolt.
One of the seatposts I bought had a replacement bolt that wasn't Campy. It was long (before I cut it down), and the bolt head had a taller profile than normal. So possibilities are out there. If you have a place like this, try there if necessary:
https://www.tacomascrew.com/
If it's threaded and made of metal, they have it.

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Thanks oneclick, what an odd an odd size. Yes, it is unlikely I'll find it at the local hardware store. Perhaps I'll get lucky and happen upon the ratcheting 10mm wrench that SurferRosa didn't pick up! I have a non-bending ratcheting 10mm wrench, not the one Andy_K recommends. Using the advice of others, it looks like the way to go. Thanks y'all

I wanted some really long ones to pair with some slitted tubing adapters and an Ideale flat rail saddle.
I think they were $12 from efbay and while I did get the setup to work ok, I didn't refine them enough to use the setup yet.
Anybody got a set of the flat rail adapters for a Campy 2 bolt they want to let go cheap?

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On at least one bike with a saddle cutout, I was able to use a 1/4" 10mm socket and extension to tighten the bolts. Obviously that would depend on where the cutout sets in comparison to the cutout.
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As obtained from my wife's younger sister. Just my size. 27" steel rims are going, along with the completely rotted tires.
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Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
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I’ve had one of those for a bit over forty years. I never had any issue with a normal 10mm open end wrench. And a very nice post for fine adjustments. My current frames aren’t 27.2mm so I’m not using it at the moment.
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Absolutely, just measure it! If you don't have the tools, take it to a real good hardware store and htey should be able to send you away with the correct numbers
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Thanks everyone for the advice and especially the humor!
Sorry for any confusion - I do not have the seatpost yet. It should arrive next week. I was hoping to get the dimensions ahead of time, before my seatpost arrives.
I thought I might get a pair of replacement hex screws ahead of time. But it sounds easy enough to keep the stock bolts. And the original Campagnolo bolts have a nice fit in the yokes.
I do have tools for measuring thread pitch, along with a variety of 10mm wrenches, sockets, nut drivers, etc. I like messing around with them, but I rarely find them in the road.

Sorry for any confusion - I do not have the seatpost yet. It should arrive next week. I was hoping to get the dimensions ahead of time, before my seatpost arrives.
I thought I might get a pair of replacement hex screws ahead of time. But it sounds easy enough to keep the stock bolts. And the original Campagnolo bolts have a nice fit in the yokes.
I do have tools for measuring thread pitch, along with a variety of 10mm wrenches, sockets, nut drivers, etc. I like messing around with them, but I rarely find them in the road.

#21
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Thanks oneclick, what an odd an odd size. Yes, it is unlikely I'll find it at the local hardware store. Perhaps I'll get lucky and happen upon the ratcheting 10mm wrench that SurferRosa didn't pick up! I have a non-bending ratcheting 10mm wrench, not the one Andy_K recommends. Using the advice of others, it looks like the way to go. Thanks y'all

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It turned out to be much simpler than I thought. I have a small 10mm wrench that is easy to fit and light enough for jersey pockets.
While at home I thought of the scrap wood set up below. A digital level app for my phone is probably more accuracy than needed.


While at home I thought of the scrap wood set up below. A digital level app for my phone is probably more accuracy than needed.


