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Campagnolo 2-bolt seatpost - bolt dimensions?

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Campagnolo 2-bolt seatpost - bolt dimensions?

Old 02-12-22, 12:34 PM
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cyclic_eric
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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:
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Old 02-12-22, 12:44 PM
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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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Old 02-12-22, 01:01 PM
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Originally Posted by Andy_K View Post
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:

Use this. I have a combo wrench like this that has no swivel, just a bit of offset - it works well, too. Go in from the back and be prepared to work the ratchet head back and forth a bunch of times. Very easy and surprisingly quick. And the wrench is useful for other things.

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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Old 02-12-22, 01:19 PM
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Definitely not designed for on the fly seat adjustments!
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Old 02-12-22, 01:58 PM
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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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Old 02-12-22, 02:11 PM
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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.
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Old 02-12-22, 03:39 PM
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M7x1
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Old 02-12-22, 04:13 PM
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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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Old 02-12-22, 04:21 PM
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Originally Posted by oneclick View Post
M7x1
not the easiest to find, a big box center unlikely to have it. I want to say 30-35mm long
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Old 02-12-22, 05:16 PM
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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.
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Old 02-12-22, 05:24 PM
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Any 10 mm offset wrench will do, no need for the expensive Campy wrench.
Tim
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Old 02-12-22, 07:44 PM
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Originally Posted by SurferRosa View Post
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.


Originally Posted by oneclick View Post
M7x1
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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Old 02-12-22, 09:30 PM
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Originally Posted by cyclic_eric View Post
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.
It's been a few years, but it was in the Crown Hill neighborhood on 8th avenue, I believe. You might try there.

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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Old 02-13-22, 01:15 AM
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Originally Posted by cyclic_eric View Post


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
Any 12 point wrench will work on the back bolt, rachet, flex, plain, etc. very easy to do with very little practice, and yes the bolts can be a bit of a challenge unless Tacoma screw is in your orbit.

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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Old 02-13-22, 09:24 AM
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Originally Posted by cyclic_eric View Post
Perhaps I'll get lucky and happen upon the ratcheting 10mm wrench that SurferRosa didn't pick up!
Plenty available on eBay:

https://www.ebay.com/sch/i.html?_fro...tchet&_sacat=0
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Old 02-13-22, 05:35 PM
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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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Old 02-13-22, 07:07 PM
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Originally Posted by Choke View Post
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.
Yup -- it would be a breeze with a Brooks Swallow, even though this bike didn't come with a Campag. seatpost.

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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Old 02-13-22, 10:31 PM
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Ive 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 arent 27.2mm so Im not using it at the moment.

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Old 02-13-22, 10:59 PM
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Originally Posted by Moe Zhoost View Post
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.
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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Old 02-14-22, 12:42 AM
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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.
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Old 02-17-22, 06:14 PM
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Originally Posted by cyclic_eric View Post


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
If you're worried about finding the bolt, I would say first take your bolt to the hardware store and get them to measure it - write it all down. Then go to their stacks of Vidmar shelves or whatever where you can find if a steel bolt of the correct head, length, shaft diameter, and shaft threading is available for you. If you can't find one, take your little sheet of specifications and search on the McMaster-Carr website, or call them and get direct assistance. If you have a choice, take a good look at the available finishes or platings which may be available to you. Hardened steel is good, but it can rust. I believe Campy bolts were originally chromed, but I'm not sure they can be duplicated. This is another example of "please try not to lose the original fasteners from your vintage bike parts."
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Old 02-17-22, 10:01 PM
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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.



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Old 02-17-22, 10:38 PM
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use a 10 mm wrench
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