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jischr

I'm gonig to repaint my frame due to numerous chips and a couple spots that are rusting. The only thing I haven't been able to removed is the upper and lower headset races. Are these threaded or pressed in? If pressed, is it a really tight press as in don't try removing with a drift?

The Vitus tubing sticker says 971 but the top tube is stamped V983. Do I presume the three main tubes are 983? I couldn't see a stamp on the chromed forks although there is a 188 stamped on the steering tube.

Thanks,

John

verktyg

John,

The top and bottom headset cups are pressed into the head tube. There's a special tool to remove these but you can gently remove them with a drift. Move it around so that you can apply even spaced impacts so that it comes out straight.

http://tinyurl.com/ba57r8

There are also special tools for removing the crown race from the fork. You can use a drift to gently remove it.

I suggest that you try to find a shop with the proper tools to face off the top and bottom of the head tube and also a 27mm cutter to dress the fork crown.

Find someone who KNOWS what their doing before you commend your irreplaceable prize to the hands of a HAMMER MECHANIC!

You can use a long 1/2" bolt and nut with large flat washers to press the cups back in. You can use a heavy walled pipe with a 1" ID to drive crown race on to the fork.

In Super Vitus 971 tubing the three main tubes have 0.9mm wall thickness in the butted areas and .06mm wall thickness in the rest of the tubes. SV 971 tubing dimensions are the same as Columbus SL tubing.

Super Vitus 983 is made from a higher strength higher alloy steel like Columbus Nivacrom. I think that SV 983 has 0.8mm x 0.5mm wall thicknesses.

My 1980 Bertin Team bike has Super Vitus 971 decals but you can see SV 980 stamped into the 3 main tubes. SV 980 is even lighter than SV 983 but probably not made from as strong an alloy steel as SV 983. The bike weighs in at ~19 Lbs. with sewups and a Brooks Pro saddle.

My 1984 Gitane Super Corsa and TdF are both made of SV 983. They're really supple smooth riding frames.

By comparison, most of the Reynolds 531 frames built in the 70s and early 80s used heavier gage tubes. The wall thicknesses on the main tubes were 1.0mm x 0.7mm. Heavier gage tubing allowed the use of less skilled workers to braze these frames. Thinner wall thickness tubes are more prone to overheating thus the need for more skilled workers.

Only the top tubes and down tubes are "double butted". Most butted seat tubes are only butted at the bottom where they go into the bottom bracket. Except for steering tubes the rest of the tubing isn't butted but may have tapered wall thicknesses.

Chas.

vanhelmont

John,

I came across Dave Moulton's ideas for headset removal and installation.

http://davesbikeblog.blogspot.com/2007/06/headset-removal-and-replacement.html

When I wanted to remove a cup, I used a piece of pvc tube, and split it like he did the copper tube. Then when I pushed it into the head tube, I put in a tapered piece of wood to expand the split end so it would push on the inside of the headset cup instead of sliding on through it, and hit the end of the tube to remove the cup. I used the pvc rather than copper because I had it there in my garage, so either one should work fine. Just to be sure I applied even pressure, I turned it a little between blows.

Dave

vanhelmont

Chas,

I didn't realize 531 was that thick back then, but it makes sense. they use a 26.4 mm seat post, with a 28 mm seat tube, so the seat tube should be (28 - 26.4)/2=0.8 mm. Or maybe they allow 0.2 mm clearance, so the tube is 0.7mm. My 501 Trek has (28.6 - 27.2)/2=0.7 mm, and I have read that 501 was 0.9mmx0.6mm. I think by that date most 531 tubesets were 0.8 mm x 0.5 mm. It will be interesting to see how the Super Corsa's ride compares to the Trek.

Dave

verktyg

Dave,

There are so many experts and opinions and conjecture and pure bull pucky about bicycle tubing that it hard to sort out the facts.

This information was gleaned from 2 sources and applies to the wall thickness of the 3 main tubes in Reynolds bicycle tubing from the late 60s to mid 70s.

The first source was the Reynolds' "Stock List" that had all of the sizes and styles of bicycle tubing that they offered in the early 70s along with prices and ordering information. Unfortunately I can't find my old Reynolds Stock List.

My second source is "DeLong's Guide to Bicycles & Bicycling" 1974 Edition with data that was pretty much taken from the Reynolds Stock List.

The UK still used Imperial (inch) measurement standards at that time. Tubing wall thickness was specified in British Standard Wire Gage or SWG dimensions. For example the main tubes were described as 20/23 or 21/24.

Here's a conversion chart from SWG to inch to mm:

http://en.wikipedia.org/wiki/Standard_wire_gauge

Up through the late 1960s (maybe even later) Reynolds produced "A" Quality tubing made of Carbon rather than Alloy steel for entry level racing bikes. I saw a number of Spanish Zeus bikes plus a few other less expensive European sport bikes made with these tubes.

The next step up in quality was Reynolds 531 Straight Gage main tubes. They were available without any butting in the following wall thicknesses:

20g 0.9mm
21g 0.8mm
22g 0.7mm

Reynolds 531 straight gage main tubes were frequently used on mid level British bikes in the early 70s.

Reynolds 531 butted main tubes came in the following wall thicknesses:

18/20 1.2mm/0.9mm (for tandems and heavy duty frames)

19/22 1.0mm/0.7mm
20/23 0.9mm/0.6mm
21/24 0.8mm/0.5mm

22/24 0.7mm/0.5mm (531 SL top and seat tubes)
22/28 0.7mm/0.375mm (753 top and seat tubes)

Seat stays, chain stays and fork blades were also available in different wall thicknesses.

Reynolds had some tube sets of sorts that they described as Tandem, Club, Sprint and so on in the Stock List but they would make up any kind of sets that you wanted as long as they were purchased in quantities of 100 or more sets of tubes.

They eventually brought out boxed sets of 531 tubing with 21/24 top and seat tubes plus 20/23 down tube (plus light weight forks and stays). Later they released 531 SL tubing sets that had 22/24 top and seat tubes 21/24 down tubes plus light gage forks and stays.

Reynolds, Columbus and other tubing manufacturers were pretty conservative in their wall thickness recommendations. They could ill afford to have a frame failure in a big race. 1.0mm/0.7mm main tubes were/are recommended for "touring" frames, reason being the possibility of someone carrying up to 50 Lbs. of camping gear.

A lot of pro frames were made from heavier gage tubing also. Many racers only had one bike. It had to be strong enough to avoid failure in use plus plus survive rough handling by support people, and the inevitable crashes.

Here's a link to a reasonably accurate history of Reynolds:

http://tinyurl.com/bj6e8a

Chas.