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-   -   Two Bolt Seatposts (https://www.bikeforums.net/classic-vintage/1288861-two-bolt-seatposts.html)

Markeologist 02-24-24 08:21 AM

Pretty sure both the Suntour Superbe Pro with polished finish and its near twin, the unpolished XC came in 27.0.

https://cimg6.ibsrv.net/gimg/bikefor...c0128e362.jpeg

oneclick 02-24-24 08:40 AM


Originally Posted by kroozer (Post 23165001)
Jean-Paul Routens (JPR) made a 2-bolt seatpost that adjusts with allen wrenches from the bottom side.

Which is fragile; the clamping bit is cast, not forged:

https://www.bikeforums.net/classic-v...post-woes.html

Aardwolf 02-24-24 08:54 AM


Originally Posted by Markeologist (Post 23165933)
Pretty sure both the Suntour Superbe Pro with polished finish and its near twin, the unpolished XC came in 27.0.

Looks to me like the Superbe Pro has hex bolts with access from below - look at 2nd photo in Velobase entry.
Also Superbe is double clamp and it's a rebranded Sugino Mighty according to Velobase.


Superbe Pro: https://www.velobase.com/ViewCompone...m=105&AbsPos=3
Superbe: https://www.velobase.com/ViewCompone...89b04&Enum=105

JohnDThompson 02-24-24 10:14 AM

Avocet also offered a two-bolt post, with both bolts accessible from below. But the bolts are only 5mm diameter, and breakage issues have been reported. FWIW, mine hasn't broken (yet).
https://velobase.com/CompImages/Seat...0BB17EEDA.jpeg
https://velobase.com/ViewComponent.a...m=105&AbsPos=0
https://cimg7.ibsrv.net/gimg/bikefor...8d58996690.jpg
https://cimg8.ibsrv.net/gimg/bikefor...bc0da4ce6a.jpg

Aardwolf 02-24-24 10:27 AM

Seems to me it might be possible to fit a hex bolt (access from below) to the standard Campy type mechanism (access from above).

Of course I'm just guessing since I don't have one yet.
And if I had one I really wouldn't want to break it by trying.
But if I had two ...

JohnDThompson 02-24-24 11:34 AM


Originally Posted by Aardwolf (Post 23166043)
Seems to me it might be possible to fit a hex bolt (access from below) to the standard Campy type mechanism (access from above).

Maybe. But you'd need to fit threaded inserts into the upper rail clamps for those bolts to work.

MooneyBloke 02-24-24 11:54 AM


Originally Posted by juvela (Post 23165159)

How in blazes do they get "HUPEL?" I'm not a Slavic languages scholar by any means, but that looks like it ought to be "super" written in a very stylized Cyrillic alphabet.

jPrichard10 02-24-24 12:04 PM


Originally Posted by MooneyBloke (Post 23166132)
How in blazes do they get "HUPEL?" I'm not a Slavic languages scholar by any means, but that looks like it ought to be "super" written in a very stylized Cyrillic alphabet.

Yes, this is an attempt at "Super."

I can see how in Japan they got to Super, but Hupel is a stretch. Trying to think of any linguistic reason for this.

As far as saddle choice with two bolt seatposts, I am quite happy that I use "carved" saddles that let me access the bolts from the top.

I consider these types of seatposts an extra security measure from would-be thieves.

bikingshearer 02-24-24 12:30 PM


Originally Posted by steelbikeguy (Post 23165222)
I'm not sure that a flex wrench is required, but it might be handy.
I've been using a 12 point combination wrench, and can't recall any large amount of effort or frustration.


https://cimg6.ibsrv.net/gimg/bikefor...f73f8913fb.jpg

Steve in Peoria

In my experience, it depends on the saddle. With a Brooks Pro, B17 ort Swallow, or with any saddle with a a lot of space along the sides i which to stick a wrench. going from the side with a regular wrench or the Campy wiggly one is . . . tolerable. It is still much easier to use the ratcheting wrench shown. Even a ratcheting wrench without the swivel head is much better than a regular wrench or the Campy wrench.

Most saddles, however, including almost all plastic-based saddles, have very little side clearance, making getting any wrench, ratcheting or not, in from the side unpleasantly difficult. Yeah, you can bend up one of the skirts, but it is a PITA. That means going in from the rear. Using a ratcheting wrench for that means a lot of very small ratcheting back-and-forth movements. Using a regular wrench means making one very small wrenching movement, taking the wrench off, resetting the wrench, making another very small wrenching movement, and repeating about 100 times. It gets old very, very quickly. Doable, but extremely tiresome. This tiresomeness factor also applies to going in through the side, BTW.

I say: just get the ratcheting wrench.

merziac 02-24-24 02:35 PM


Originally Posted by JohnDThompson (Post 23166034)
Avocet also offered a two-bolt post, with both bolts accessible from below. But the bolts are only 5mm diameter, and breakage issues have been reported. FWIW, mine hasn't broken (yet).
https://velobase.com/CompImages/Seat...0BB17EEDA.jpeg
https://velobase.com/ViewComponent.a...m=105&AbsPos=0

I had some break a couple years ago, lack of lube at install may have been part of it. :twitchy:

Ace hardware in Newport had replacements so it worked out ok. ;)

Aardwolf 02-24-24 03:03 PM

Hmmm, Avocet bolts are advertise on Ebay
https://www.ebay.co.uk/itm/364490608...IAAOSwUMFjs5b2

https://cimg3.ibsrv.net/gimg/bikefor...5562ef5b0c.png
Anybody think those might fit a Campy style mechanism ?

Garthr 02-24-24 04:10 PM

Nitto NJS NJ-SP72 posts come in larger variety of diameters than the stuff for mere mortals ..... teeheeheee ...

I have the Nitto S84 twin bolt which used the same head design. Use any superlative you want for it. I call it the Frog head design because from the side it's rather obvious !

This is about the best price with shipping I've seen for the NJS Jaguar SP72 (W44) That's standard 44mm rails. (They also make a 30mm for version).
https://www.amazon.com/Nitto-NJ-SP72.../dp/B004KLEWIG


https://cimg7.ibsrv.net/gimg/bikefor...2c81b48d17.jpg

Markeologist 02-24-24 04:17 PM


Originally Posted by Aardwolf (Post 23165964)
Looks to me like the Superbe Pro has hex bolts with access from below - look at 2nd photo in Velobase entry.
Also Superbe is double clamp and it's a rebranded Sugino Mighty according to Velobase.


Superbe Pro: https://www.velobase.com/ViewCompone...m=105&AbsPos=3
Superbe: https://www.velobase.com/ViewCompone...89b04&Enum=105

Your criteria were 27mm, more adjustable than a SR LaPrade and better looking which describes both the Superbe and XC. Both nuts on top side of clamp (see photo I posted, not mine borrowed) fit down into recesses so you don’t need a wrench to hold them. The level of finish certainly seems well above Sugino’s offerings too.

bulgie 02-24-24 05:08 PM


Originally Posted by merziac (Post 23166274)
I had some break a couple years ago, lack of lube at install may have been part of it. :twitchy:

Ace hardware in Newport had replacements so it worked out ok. ;)

I also had two Avocet bolts break, luckily not both at once, two incidents. Probably the front bolt broke both times (but too many years ago to remember), since that's the one loaded in tension by your weight. It's possible to put more load on the rear bolt if you sit all the way on the nose of the saddle, but most people don't.

I'd caution against using hardware store bolts unless they carry high-strength heat-treated bolts. Metric bolts go by strength "class", rather than "grade" as with SAE bolts. I'd try for class 10.9 or higher (there's also a class 12.9, super strong), since the ones on the Avocet have been shown to be marginal as-delivered, and they might have used high-strength bolts. So you don't want to substitue a lower-strength one to do the same job.

I think class 10.9 are roughly twice as strong as generic hardware store bolts, maybe more than twice.

Aardwolf 02-24-24 05:26 PM


Originally Posted by Markeologist (Post 23166360)
Your criteria were 27mm, more adjustable than a SR LaPrade and better looking which describes both the Superbe and XC. Both nuts on top side of clamp (see photo I posted, not mine borrowed) fit down into recesses so you don’t need a wrench to hold them. The level of finish certainly seems well above Sugino’s offerings too.

According to "General Information" on Velobase the Superbe (not pro) is a rebranded Sugino Mighty SP-2C
https://www.velobase.com/ViewCompone...89b04&Enum=105

Superbe Pro is definitely another level of better, but they go for a lot more money
Whereas I think I can get a Sugino Mighty for £45 and the flex wrench for £10ish.
The SR LaPrade I'm currently using was £15.

Here's my compilation so far:
https://cimg6.ibsrv.net/gimg/bikefor...8c468c415e.jpg

bulgie 02-24-24 05:46 PM


Originally Posted by Aardwolf (Post 23166425)
Here's my compilation so far: [snip]
https://cimg0.ibsrv.net/gimg/bikefor...346abfa4e9.jpg

If the "5 mm hex" refers to the wrench, then that should be 4 mm. The bolt is M5, but the wrench is a 4. On the ones I owned anyway.

Maybe add Weyless ('70s) to the list, though they're rare nowadays. Very lightweight. I think they came in 27.0 but I can't swear to it...

Aardwolf 02-24-24 06:16 PM


Originally Posted by bulgie (Post 23166440)
Maybe add Weyless ('70s) to the list, though they're rare nowadays. Very lightweight. I think they came in 27.0 but I can't swear to it...

There's one on Ebay from the US for $270: https://www.ebay.co.uk/itm/265657567141
192g apparently.
Fairly sure it's not worth it :)
Does adjust from the bottom though.

bulgie 02-24-24 06:33 PM


Originally Posted by Aardwolf (Post 23166476)
There's one on Ebay from the US for $270: https://www.ebay.co.uk/itm/265657567141
192g apparently.
Fairly sure it's not worth it :)
Does adjust from the bottom though.

Despite sharing the M5 bolts with the Avocet, I never heard of one breaking a bolt. Luck, or small numbers produced? Or maybe something about the leverage, from where they're positioned, they aren't stressed as much from your weight. I think (without a lot of analysis) that last bit is the main reason, but the first two might come into play as well.

When I made my first custom frame for myself in '77, I made it with a "seat mast" (though we didn't call it that back then) — seat tube of the frame went all the way up to the saddle-clamping hardware, no seatpost. I used the clamping hardware from a Weyless that someone had ruined the shaft on, taken from the trash bin. Worked great. Though nowadays I think seat mast frames are dumb, and I'm embarassed I ever made one! Hey, I was a teenager, my prefrontal cortex wasn't fully developed yet.

merziac 02-24-24 09:46 PM


Originally Posted by bulgie (Post 23166407)
I also had two Avocet bolts break, luckily not both at once, two incidents. Probably the front bolt broke both times (but too many years ago to remember), since that's the one loaded in tension by your weight. It's possible to put more load on the rear bolt if you sit all the way on the nose of the saddle, but most people don't.

I'd caution against using hardware store bolts unless they carry high-strength heat-treated bolts. Metric bolts go by strength "class", rather than "grade" as with SAE bolts. I'd try for class 10.9 or higher (there's also a class 12.9, super strong), since the ones on the Avocet have been shown to be marginal as-delivered, and they might have used high-strength bolts. So you don't want to substitue a lower-strength one to do the same job.

I think class 10.9 are roughly twice as strong as generic hardware store bolts, maybe more than twice.

Yeah, Tx Mark, I'm well aware.

So they were way better than the broken ones and I'm pretty sure they were bound up and too tight as well. They are too small IMO but the Ace ones were not generic, they were black oxide like the originals and that bike sees minimal use so is probably ok.

I've used plenty of hardware store stuff in a pinch and at the drag strip, also on the road and everywhere in between, never had a failure from them and am pretty good assessing they're viability absent actual ratings.

Most of the time the stuff at the better hardware stores can get you by if you know something about it.

And don't get me started on torque to yield cylinder head bolts. ;)

Aardwolf 02-25-24 03:55 AM

FYI: Hilary Stone is retiring.
.
I am sorry that the item(s) you enquired about are no longer available. I am retiring and have sold almost all of my stock. I will be continuing with some items such as specialist chainrings 86mm, 122mm, 151mm and 116mm BCD, the Andel chain sets and rings, VAR crank extractors, Kalloy/Ritchey seat pins and the occasional other special item including a few frames. These will be announced on my Facebook page – https://www.facebook.com/HilaryStoneCycles
.
Rats.

Aardwolf 02-25-24 07:57 AM

Here's something for Xmas: 10mm Ratchet Flex Head Keychain Ring 72-tooth
https://www.amazon.co.uk/FACULX-Keyc...DV/ref=sr_1_27

https://cimg4.ibsrv.net/gimg/bikefor...a48552f9d4.jpg

JohnDThompson 02-25-24 08:29 AM


Originally Posted by Aardwolf (Post 23166294)
Hmmm, Avocet bolts are advertise on Ebay
https://www.ebay.co.uk/itm/364490608...IAAOSwUMFjs5b2

https://cimg3.ibsrv.net/gimg/bikefor...5562ef5b0c.png
Anybody think those might fit a Campy style mechanism ?

Not without modification of the upper rail clamps to fit those half-round nuts.

Aardwolf 02-28-24 08:01 AM

And £35 later: SR Royal 27.0, would have prefered fluted but this one was available.

It's about 10g lighter than my SR LaPrade.
It's marked "27.0" and it measures 27.0 too.
Just needs a bit of polishing.


https://cimg9.ibsrv.net/gimg/bikefor...b4bc31dac6.jpg

Mr. 66 02-28-24 08:27 AM

SR Royal, nice that is the post that I had on my high school rider. I still have it, my first instal was 1983 on my brother’s hand me down Rodriguez. I’m using it on my trek 710. I used to have my cable wrapped around. That gave it a funny wear pattern, I ended up sanding the anodized off. Good post, it has never slipped.

oneclick 02-28-24 12:07 PM


Originally Posted by JohnDThompson (Post 23166839)
Not without modification of the upper rail clamps to fit those half-round nuts.

And of the main casting - only one of the bolts has a through-hole.


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