re: Re: [CR]Super Record Seat Post Clamp

(Example: Framebuilding:Technology)

Date: Sun, 27 Mar 2005 07:30:37 -0500
From: "HM & SS Sachs" <sachs@erols.com>
To: dddd@pacbell.net, Classic Rendezvous <classicrendezvous@bikelist.org>, nickzz@mindspring.com
Subject: re: Re: [CR]Super Record Seat Post Clamp


Well, assuming the SR is like all the other one-bolt units out there that I've worked on, if you're willing to modify the surfaces a bit, here's what one shop owner taught me about a quick and secure fix: Cut a piece of medium sandpaper to fit the mating surfaces. Install and clamp down. Bingo! Instantly there are hundreds or thousands of contact surfaces supplementing the inadequate serrations. Heck, even if you use paper-backed sandpaper and it gets wet, the grit, pressed into place, isn't going anywhere. Of course, now the scrapes on the shaft are joined by tiny pits where the sunlight don't never show... It's still "almost NOS" for eBay. :-) harvey sachs mcLean VA. (This trick was so obvious after he showed it to me that I slapped myself upside the head). Nick Zatezalo wrote:
> How does one tighten this rascal so it does not slip. I have tried brute
>> force
>> and the clamp is still slipping enough to make the nose of the saddle
>> raise
>> about an inch during a ride. I am using a Selle San Marcos Regal saddle
>> and it is clamped near the front of the rails.
>>
>
> and David Snyder responded: This post's clamp relies on the bolt tension to create a wedging effect, increasing friction on the sliding, canted surfaces. Mine has slipped in the past, and the best I could do was clean the surfaces with solvent (alcohol) and lube the bolt's threads. Mine came with an alloy bolt, fwiw, and now it doesn't slip. I would want to be certain, as with certain other items (like seat binder bolts), that the bolt or bolted assembly isn't somehow bottoming out before all the bolt's tension is fully applied to the friction surfaces. I hate when that happens! Perhaps some slight roughening (and cleaning) of the friction surfaces might also help. You might also want to confirm that the lower cradle isn't cracked.