Archive-URL: http://search.bikelist.org/getmsg.asp?Filename=classicrendezvous.10907.0159.eml
Date: Sun, 5 Jul 2009 17:52:51 +0100
From: Hilary Stone <hilary.stone(AT)blueyonder.co.uk>
Subject: [CR]  De Rosa Time line

Quite a number of CR members have been aware that I have been working on =

a sort of time line for pre-cast lug De Rosas for some time. Many =

members have helped by sending pics of their frames and I'd like to take =

this opportunity to thank every one who has helped =96 I am especially =

grateful to Jack Bissell's 43bikes De Rosa page.

What I would stress that what follows is very much work in progress - I =

welcome all comments and information that will help to make this a =

reliable guide...

I have in particular details on very few De Rosa frames from the late =

1970s =96 something I do not understand...

Hilary Stone, Bristol, British Isles

De Rosa Frames pre-cast lugs

A precise and clear time line for pre-1980 De Rosas I think is virtually =

impossible =96 De Rosa at this time was quite small and the evidence from =

the frames suggests that De Rosa used a number of different lugs and =

fork crown that overlapped over quite a number of years. Almost no De =

Rosa frames from this time have any frame number.

Seatstay Cap Engraving
Team frames frequently have no seatstay cap engraving. Seat stay caps =

were also not engraved on the earliest De Rosa frames - my best guess is =

that the engraving started in the late 60s - 67 or 68.
The first version has no heart in the O of De Rosa - my present guess is =

that this changed around 1973 to the second version. The second version =

has the heart in the O of De Rosa and this continued save for a few =

exceptions to the early 1990s.
Circa 1976/77 (two frames are known) De Rosa used what appears to be a =

solid concave plug with an engraved heart on a few frames.

Lugs
Team frames frequently have no heart cutouts. There seems to be two =

broad common types of pressed lug - ones with a short point and ones =

with a long point. On present evidence it looks as the two designs were =

in use together for several years probably something like 1972=961974. The =

long point definitely started before the short point lugs which seemed =

to come into use around 1972. And there are some medium point lugs which =

seem to be from the mid 70s...
Most frames have heart cutouts in all lugs in the early 70s but there =

are a number with short and medium point lugs with only a heart in the =

lower head lug or in both head lugs but with no heart cut out in the =

seat lug. These seem to date from 1974-6.
Cast lugs were introduced around 1979/80 - the cast lug frames are =

easily distingushed from the pressed-lug frames by the extension for the =

seat bolt. These cast lugs do not feature heart cutouts.

Fork Crown
Earlier frames seem to use a wide variety of fork crowns - quite a =

number around 1972=964 use a Vagner 4-point sloping crown. A 4pt flat =

topped cast crown was adopted sometime I think over the period 1973=965. =

These normally had a heart engraved in them during the 1970s; team =

frames generally were lacking the heart.
Fork tangs were plain on the 1960s frames - they gained three round =

holes followed later by V shape slots - the later change probably around =

1976.

Bottom Bracket Shell
A shell with six slots and two hearts =96 one in the down tube tang and =

one in the seat tube tang (behind the BB) was standard for quite a long =

period. At some point =96 maybe in 1973 a large heart cutout was =

introduced on some frames - most had additional heart cutouts in the DT =

and ST tangs but some not...
Some later 70s frames used BB shells with four slots rather than six.
When the the cast lugs were introduced, a new cast BB shell was used =

with six relieved areas in the shell.

Dropouts
Campag short dropouts definitely indicate a frame built 1975 or later =

but it seems that De Rosa may have been slower to adopt the Campag short =

dropouts than some other framebuilders.

Other fittings
The earlier chainstay bridges are larger in diameter and with round =

flanges formed with the tube. By about 1970 De Rosa used a slightly =

smaller diameter round tube with diamond reinforcements. These continued =

into the early period of cast lugs.
The earliest bottle cage fittings are short studs - these continued into =

the 1970s probably until 1973/4.
Gear cable guides over the top of the BB shell were standard on De Rosas =

from the late 1960s.
Brake cable stops/guides (generally three)  and DT lever bosses were I =

think introduced c1975/6.







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