Is Columbus SL always double butted?

My backup bike is built on a Schwinn Circuit frame (1989). The tube sticker says, "Columbus Tubi
Speciali Rinforzati Acciaio CrMo Cyclex SL Tre Tubi." I interpret this to mean the three main tubes
are double-butted SL. Is that correct?

Art Harris

On Sat, 14 Jun 2003 10:30:37 GMT, "Harris" <n2ah@spam.sprynet.com> wrote:

>My backup bike is built on a Schwinn Circuit frame (1989). The tube sticker says, "Columbus Tubi
>Speciali Rinforzati Acciaio CrMo Cyclex SL Tre Tubi." I interpret this to mean the three main tubes
>are double-butted SL. Is that correct?
>
>Art Harris
>

I think that is what the 'Speciali Rinforzati' means.

If you tap the tube with a piece of metal, like a key, and move along the length of the tube, you
will hear a distinct difference in tone between the butted and unbutted sections on double-butted
tubes. On unbutted tubing, the tone will be basically the same along the whole length.

In article <hPCGa.7020$gs5.2512623@news4.srv.hcvlny.cv.net>, Harris wrote:

> My backup bike is built on a Schwinn Circuit frame (1989). The tube sticker says, "Columbus Tubi
> Speciali Rinforzati Acciaio CrMo Cyclex SL Tre Tubi." I interpret this to mean the three main
> tubes are double-butted SL. Is that correct?

Yes. Columbus does have some light-weight straight-gauge tubesets (eg "KL" and "Record") but these
are intended to be specialty items for time trials and record attempts. You're not likely to see
them used on a production bike.

There's also a couple heavier straight-gauge sets ("Aelle" and "Zeta") intended for inexpensive
frames, but anything with an "SL" sticker will be double-butted chrome-moly. The "Tre Tubi"
designation on your bike means that only the three main frame tubes are certified to be SL.

--

-John (John.Thompson@new.rr.com)

Tried mailing this to you, but you must have some sort of anti-spam thingie going on, it
bounced back.

My Voyager is made from Columbus "Tenax" (Sp?) Any data on this tubing? I doubt it's anything
special, just curious.

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Originally posted to rec.bicycles.tech:
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Re: Is Columbus SL always double butted?

Group: rec.bicycles.tech Date: Tue, Jun 17, 2003, 5:00pm (EDT+4) From: john@starfleet.os2.us
(John=A0Thompson)

In article <hPCGa.7020$gs5.2512623@news4.srv.hcvlny.cv.net>, Harris wrote:

>My backup bike is built on a Schwinn Circuit frame (1989). The tube sticker says, "Columbus Tubi
>Speciali Rinforzati Acciaio CrMo Cyclex SL Tre Tubi." I interpret this to mean the three main tubes
>are double-butted SL. Is that correct?

Yes. Columbus does have some light-weight straight-gauge tubesets (eg "KL" and "Record") but these
are intended to be specialty items for time trials and record attempts. You're not likely to see
them used on a production bike.

There's also a couple heavier straight-gauge sets ("Aelle" and "Zeta") intended for inexpensive
frames, but anything with an "SL" sticker will be double-butted chrome-moly. =A0 The "Tre Tubi"
designation on your bike means that only the three main frame tubes are certified to be SL.
--
-John (John.Thompson@new.rr.com)

May you have the wind at your back. And a really low gear for the hills! Chris

Chris'Z Corner "The Website for the Common Bicyclist": http://www.geocities.com/czcorner