miamijim

Is there such a thing like there is for Colnagos?

If there isnt would it be possible for the experts to comment on the introduction of certain features?

Dawes-man

I'm all eyes!

Picchio Special

It's very difficult, in part because De Rosa was less consistent than other marques in this regard. This was in part because De Rosa was still a low-volume producer in the 70's, making a relatively high percentage of team and custom bikes. So you see chronological overlap between features like heart BB cutouts vs. slots, long-point vs. short-point lugs, more vs. fewer heart cutouts, etc. Having said that, I know Hilary Stone has been compiling info on De Rosas since he started coming across and acquiring them a couple of years or so ago. I think we can expect a timeline from him, hopefully sometimes soon, that will at least give us a jumping off point. I'm happy to comment on features I know something about, which is a few but certainly not all of them, as with Colnagos I'm more interested in some vintages of De Rosas than others. I lose a lot of interest around 1980 when De Rosa went to cast lugs.

miamijim

From searching I know there was period when they didnt have TT cable giudes etc. Perhaps we could collectively get a rough date for the following:

1. BB cutouts
2. TT cable guides
3. Sloping fork crowns
4. Long point vs. short point lugs
5. Cast lugs versus ?? Forged? How do you visibly tell the difference?



Thanks,

Jim

Picchio Special

BB cutouts - On 70's De Rosas with pressed lugs, you generally find either a heart cutout or slots. The IC lugged bikes I've seen, i.e. through the 80's, I believe have a relieved shell where the slots do not perforate the shell (cables routed under the shell.)
TT cable guides - circa 1975.
Sloping crowns - from the early 80's throughout the decade, coexisting with the flat version.
Long-point vs. short-point lugs - these overlap on bikes until maybe 1975, when the short-points then predominate. (Can't say longer points don't occasionally appear on later bikes, though.)
Cast lugs - from about 1979. The IC lugged bikes are easy to spot because the seatlug ears are "kicked up" - the top of the ears actually forms a shelf at the same level as the top of the seattube. On pressed lug bikes, the ears are positioned lower.

Picchio Special

A few pics of my circa 1977 bike showing some of the details common on bikes from the mid-late 70's:

https://www.flickr.com/photos/2358521...7618581982271/

Citoyen du Monde

Well into the 90's, it was still possible to order a frame with features as desired. If De Rosa had the parts available, they were more than happy to build it to your specification. I went to the factory in 1988, was measured up by Ugo and made specific requests such as flat fork crown and specific seat stays. The frame was very close to a stock geometry but did have the specifications that I asked for. They did mess up a bit with the requested paint scheme, but all was fine as soon as I took teh bike out for a ride.

My two 1960's De Rosa frames have many items that are different one from another.

I think that attempting to make a timeline for non production frames is foolhardy. This is not like Colnago which is for all effects a production frame that is farmed out.

gomango

Citoyen-Thank you for this information. I recently unearthed a very nice older Primato and faced some challenges id'ing the model year and tubing. Other than some helpful forumites, it took an email to DeRosa for further explanation. They, as well as another local owner of a similar Primato, reported that my wife's bike was part of a special order by a local shop. There were other interesting elements to this such as a copy of the original invoice that list these Primatos as a "Racing" model with no other special details. The paint was also a special order item. The closest I have seen to this model is the mid-90's Giro D'Italia. So, a little tricky to figure this out. I am taking pictures of the bike to Italy this summer to talk to folks who also may be helpful.

gridplan

You really need to issue a warning before posting links like that. Now I have drool all over the keyboard. Beautiful bike. I love everything about it, except maybe the tires.

Picchio Special

Hey, I posted an apology on there about the tires. They're what I could afford to stock up on and happened to have on hand.
Those pics were actually tentative ones I took when Hilary was working on his timeline. How ironic in light of this thread that he just today posted his first tentative De Rosa timeline to CR:

"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. I am especially
grateful to Jack Bissell's 43bikes De Rosa page.

What I would stress is 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 - 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. 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?1974. 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?4 use a Vagner 4-point sloping crown. A 4pt flat
topped cast crown was adopted sometime I think over the period 1973?5.
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 ? 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 ? 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."

gridplan

Sorry I mentioned it. Things like tires and handlebar tape don't matter much to me. They wear out and can so easily be changed for something different. You have an incredible bike any way you cut it.

Picchio Special

I totally deserve the stick for those tires - I took some stick at our east coast ride in April, too. I tried to get some Veloflex Paves on those rims, but no dice. Those were my tires of last resort. I thought about substituting some tan sidewall Bontragers, but reading up on them they seemed prone to problems. At least the ones I have on there are durable. I would have changed the tape, but I'm trying to get as much mileage out of those original globe logo hoods as possible. They're crunchy, but OK for riding for the time being.

tremolo1965

I'm new here. I have just purchased a 1977 De Rosa with full history from the original owner who brought it back from Florence. It has the same unusual seat stay caps as Picchio Special's bike. It's in nice original shape with the exception of some significant pitting on the forks, otherwise very minor chips / 2 small surface rust issues. Early pre-CPSC Super Record...Mavic GP 4s with Vittorias. This will be my second De Rosa, had an SLX years back and loved it. I'm going to tune it up and ride it every day, total keeper and an upgrade from the 1973 Suburban I've been riding! Will post pics as I go along...pearl white.

Cheers,
Chris

gomango

Welcome.

Can't wait to see big pics and lots of them.

753proguy

Now this is a very informative thread - thanks to everyone that is contributing!

tremolo1965

She's a pretty special bike, at least to me..

I do feel a custodial obligation, I believe in riding and maintaining these bikes..and that is why I have her. I've owned a few Italian bikes and they just inspire me to spend time outside, ride, and stay healthy...

I won't be doing a restoration (just a lot of cleaning), but she won't be ridden hard and put away wet, either...

As soon as I have an opportunity to post some quality pictures, I will.

Chris

tremolo1965

Here are a few pics. I don't know how to post them properly on here so here's the Flickr link: I will try to take some better shots soon. I'm thinking she's approximately a '77...broken in and beautiful!

https://www.flickr.com/photos/5114799...7629166902913/

gomango

I hope you don't mind.

I'll take them right down if you do.

Again, welcome to the forum. You have an incredible bicycle.

Out of my league to authenticate these early De Rosas.

tremolo1965

Thank you for posting the pics, Gomango! I Don't mind at all - I am here to learn and share.

gomango

No problem.

This has been happening so often lately, we need an easy to follow pic posting primer!

Or maybe we have one and I don't know where it is located.

I love the color of the frameset, and everything looks like it is very nice condition.

KonAaron Snake 

OHHHH MY! If that doesn't get your juices flowing, you might want to call a hospital.