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Old 04-07-16 | 11:53 PM
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verktyg
verktyg
 
Joined: Jul 2006
Posts: 4,034
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From: SF Bay Area

Bikes: Current favorites: 1988 Peugeot Birraritz, 1984 Gitane Super Corsa, 1980s DeRosa, 1981 Bianchi Campione Del Mondo, 1992 Paramount OS, 1988 Colnago Technos, 1985 RalieghUSA SBDU Team Pro

Originally Posted by Narhay
Does your standard PX-10 steerer with a stronglight competition headset generally fit a Nuovo record headset? 38/39.4mm stack height with the stronglight (plus a Mafac hanger), 42mm with Nuovo record.
Several things to consider...

First off, what's wrong with the Stronglight V4 Competition headset on you PX-10? Or... why do you want to change to Campy?

The Stronglight V4 headsets were bullet proof. Since 1973 I've only seen 1 or 2 that failed due to indentations or other modes (Don't even go into brinelling, false brinnelling, fretting, spalling, indexing and other misused, misunderstood terms. Without analytical testing in a lab, the only thing that can be said is that the headset bearing races are indented).

During that same time I've seen many dozens of Campy lower headset cups and crown races with indentations.

In the mid 70's we had so many problems with Campy NR headsets indenting that we took a large number of different brands of headsets to a friend's machine shop and had the Rockwell Hardness tested. Stronglight, Zeus, Shimano, Tange and a few others were ~60 Rc hardness. Most of the Campy lower race parts were under 50 Rc!!!


One problem you will run into switching to a Crampy headset is you will probably not have enough threads for the top lock nut if you use any spacers or a center pull brake cable hanger. You should have at least 5 turns of threads.

Here's a Motobecane (actually Motoconfort) frame that someone replaced the Stronglight V4 headset with a Campy. Notice there are only a few threads of engagement on the steerer. With that few threads, the top lock nut will keep coming loose!




Another thing, the bearing seat on your PX-10 is 27.0mm. The crown races on Campy headsets are 26.4mm. The bearing seat can be cut down but the chrome plating tends to chew up the cutters on the facing tools. The best way is to grip the steerer in the chuck on a lathe and turn down the seat with a carbide tool bit.




Headset Stack Height:



Details on how to figure Stack Height. Please read descriptions below the pictures in the Flickr album:

https://www.flickr.com/photos/282672...57625424641013


PS, I have Campy headsets on a lot of bikes... But I generally prefer other brands.




verktyg

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Last edited by verktyg; 04-08-16 at 04:13 AM.
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