[Classicrendezvous] Re: Favorit and seatpin diameters


Example: Production Builders:Cinelli

Date: Wed, 04 Oct 2000 10:18:56 +0100
From: "Hilary Stone" <Hilary.Stone@Tesco.net>
To: Stacey Baker <veritas23@yahoo.com>, classicrendezvous@bikelist.org
Subject: [Classicrendezvous] Re: Favorit and seatpin diameters

Favorit was (and is?) the premier Czech bike manufacturer which celebrated its 100 anniversary in 1974 and make bikes under quite a few other brand names too. When I was at the 1993 International Veteran Cycle Rally in Prague we were all given a history (in Czech) of Favorit published in 1974. They were the Czech equivalent of Raleigh in England manufacturing everything from shoppers to top end road bikes. Not many are aware of just how advanced engineering was in the Czechoslovakia and the tubing may well have been home brewed chrome-moly. If the frameset is reasonably light I think you can be assured that the frame was one of their top ones. Don't forget however that it may be a little heavier than we have become accustomed to in the past ten years. Most manufacturers in France, Italy and Belgium used heavier gauge quality tubing for many years in order to ensure a long life over what could be very indifferent road surfaces. Seat pin size (except for Cinellis) is certainly one way of determining whether a frame is at least fitted with a butted seat tube. Seat tubes are almost always single butted (whether Reynolds, Ishiwata, Tange or Columbus) if they are not plain gauge. The exceptions are very few ­ Tange Super Light is one set which offered a 0.6/0.4/0.6mm double butted seat tube. The standard 531 tubeset as supplied by Reynolds included a single butted 0.8/0.55mm seat tube. Thicker walled seat tubes were optional and are more commonly found in large frames, tandems or ladies frames. Columbus SP is 0.7mm at the thin end. Some confusion arises from heat distortion caused during building. The calculations: Tube diameter is 28.6mm (except in rare metric sized tubing ­ early 753 for example) ­ (2 x 0.55mm) = 27.5mm. Allow 0.1mm and you get 27.4mm seatpin which is what the very best 531 frames which hawe a minimum of heat input use. But usually there is some distortion so a clearance of 0.3mm is more normal with a 27.2mm seatpin. Heavier gauge seat tubes from Columbus or Reynolds are typically butted 0.7mm at the thin end. 28.6 ­ 1.4mm = 27.2mm and with a working clearance either 26.8mm or 27.0mm depending on the level of distortion. Plain gauge tubed frames don¹t take a 26.8mm seatpin except for the likes of Coplumus Record which was very thin walled plain gauge and only used for the lightest track frames. Most top quality plain gauge seat tubes (eg Reynolds) have 1.0mm thick walls. 28.6 ­ 2mm = 26.6mm so 26.4mm is the standard size for Reynolds plain gauge seat tubes ­ the heavier tubes distort less so working clearances can be a little tighter. Hilary Stone

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>From: Stacey Baker <veritas23@yahoo.com>

>To: classicrendezvous@bikelist.org

>Subject: [Classicrendezvous] Czechoslovakian Bike

>Date: Tue, Oct 3, 2000, 11:23 pm

>


> Hello Folks,

>

> Stacey Baker from Virginia. Anyone ever heard of a

> bike called 'Favorite'? I bought it new in the fall

> of 1973, (another story), it was made in

> Czechoslovakia, all Campy NR except for brakes and

> pedals, (another story). The rear derailler is dated

> '72. The frame, while very nicely done lugwork with

> wrap around seat stays, is unknown as far as the

> tubing is concerned. No name on the dropouts. About

> twelve years ago, in reply to my inquiry, no less a

> personage than Fred DeLong at Bicycling also said he

> had no idea as to the tubing, but he suspected

> Columbus. If anyone has seen a bike similar to this

> one, or has any info, would love to hear it. I still

> ride it, in the late eighties did some racing, and

> still stubbornly stick to my Brooks Pro saddle (small

> rivets)!! Thanks for your help.

>

> stacey