Monday, March 11, 2019

OBAT #7: Cromovan Dura-Ace

Proving one of three points yet again:

  1. My translation of technical Italian is lacking
  2. Romance languages are terrible for technical descriptions, often scribbling a series of random 5-syllable words to describe something like "stiff"
  3. How much detail can you really give about a great steel frame?

Page 87-89, 136 of La Bicicletta, May 1993. As usual, translation below the images.

Bianchi Cromovan Dura Ace

by Bebo Facciavento / photos by M. Venditti

Classic in its famous "celeste", now modernized with a fading paint style, this special bike from the Bianchi Reparto Corse utilizes the light and rigid tubing Oria Cromovan, Tig welded.

In 1885 Edoardo Bianchi founded the "Italian Bicycle Factory": it was the era of the high wheeler, difficult to ride due to its enormous front wheel. It was also the era in which serious and intense research began to bring ergonomic updates, until arriving at the necessary simplicity and efficiency of what we have today. Bianchi immediately made its contribution, presenting a bicycle with wheels of the same diameter, shod with pneumatic tires, giving relief to the spines of cyclists of the day. The final years of that century saw the industrialized planning of the bicycle and its accessories, and the "bottega" of Edoardo Bianchi transformed into an giant who would become known outside of Italy, brought by names like Girardengo, Bottechia, Belloni and Pavesi. Then came Coppi followed by Gimondi, Argentin and Bugno, who wore the rainbow stripes of the world champion while aboard a celeste Bianchi. And many more, too many to name here...

The world of racing has always been Bianchi's playing field, outside of a brief and recent reflective pause. For its return to racing the brand from Treviglio has launched a renewed production of frames and racing models by creating a new company, the Bianchi Reparto Corse Srl, that has the stated goal of designing and production the line of bicycles destined to be ridden by professionals and those who desire a bike of this level. The continuity of the traditional characteristics of each piece is assured by the structure of the Reparto Corse, that is equipped with the most modern research and development technology available. Frame production is instead trusted to the human element, where the experience and sensibility of an artisan cannot be substituted by a computer.

The model tested here is an example of the latest generation: it is called "Cromovan Dura Ace", and the name of course is made up from the tubing and component group chosen for the occasion (by which can be substituted upon request). The frame is assembled with Oria Cromovan tubing, a blend of steel with chrome, molybdenum and vanadium. It is a cold drawn tube, double butted with wall thicknesses that range from .5mm to 1mm, depending on the location. The center sections are slightly ovalized, in particular the top and down tubes, whose elliptical sections are oriented opposite each other. The contrasting forces should resist twisting and loss of power through flex, assuring the rigidity of the parts subjected to torsion and lateral hits: all without neglecting the right flexibility to absorb impacts from the terrain. The profile of the down tube increases the torsional rigidity necessary for sprinting and steering stability, limiting its work to compression and traction. A subtlety of Cromovan tubing is accompanied by a high strength (120 kg per cubic mm): the result is a frame that weighs between 1600 and 1800 grams, plus 650-700 grams for the fork, depending on the size (this complete bicycle weighs under ten kg). It saves a few hundred grams in respect to the standard, which are useful to the rider who rides thousands of kilometers during the year, and all this without affecting the stability and durability of the bike.

The qualities of the Cromovan tubing that permit both a rigid frame with the appropriate flexibility for comfort are maintained by the choice of Tig welding (as opposed to using lugs). The result on our test model is noteworthy: upon close inspection, the welds are very well executed.

Regarding the assembly, it's worth noting the lack of a chain stay bridge: with its corresponding seat stays, they form a compact and solid rear triangle. This configuration will show its benefits while climbing and accelerating, where frequent attacks typically flex the rear triangle. The rear dropouts are forged and brazed: they feature a vertical exit, to assure quick removal of the rear wheel, and additionally have micro-adjustment screws. The rear brake cable housing and rear derailleur are internal for a cleaner look: the first through the top tube and the second through the drive side chainstay. The fork is made of Cromovan: the reinforced steer tube is Tig welded and the dropouts are brazed. It is a unicrown fork, a style growing in its use on road bikes, which leaves the blades in their full length to better absorb hits and road vibration.

The seat tube is 53.5cm while the top tube is 55cm center-to-center (Bianchi calls this a size 55, measuring the seat tube center to top), the rear triangle is 40.3cm with a wheelbase of 99cm. Fork rake is 4.2cm and the bottom bracket sits 27.5cm from the ground. The head tube angle is 72.5 degrees while the seat tube is 73 degrees. It is a well balanced frame, solid for its tight triangles. It gives the impression of lightweight and agility.

Once welding is checked, before heading to finishing, the frame is treated to an antioxidant process and then immersed in a chrome bath, in order to protect the frame in case of accidental paint removal. The paint process is as such: primer coat, paint/color base coat, fade coat, final clear coat; each coat dried at 140 degrees. The result sets the standard from an aesthetic standpoint as well as for durability. For colors, Bianchi has ceded and added additional choices to its historic shade, Bianchi Celeste: blue marine, matte blue, white pearl, metallic red, red-black fade, green fade to Austrian blue, Ferrari red and matte violet. It is a wide range of shades and sufficient to please the needs of many. Our test bike is in the traditional celeste, updated with a slight fade and interrupted only by the simple logos, which from this year forward are masked and painted, and features a chromed rear triangle and fork. The look is noteworthy and no imperfections were to be found.

This Cromovan is equipped with Shimano's top group, the Dura Ace STI with Dual Control shift/brake levers: these shift onto an eight speed, 12/21 Hyperglide freewheel and the new crankset (the big ring has six shifting ramps on the inside that facilitate upshifts; also the bb axle has been narrowed, resulting in a smaller distance between pedals) with 170mm arms and 39/53 teeth. The dual pivot brakes are very effective, while the pedals are French Look PM 76.

The wheels, having a 66.5cm diameter, are made from FiR Tour hard anodized alloy rims with double stainless eyelets, Aci stainless double butted spokes 2.0/1.8/2.0, and Michelin Hi-Lite Supercompetition HD 700x20C clincher tires.

The ITM Italia Pro handlebar is 42cm in 7075 black laser-etched anodized aluminum, wrapped with Bike Ribbon Bianchi tape. The stem is also by ITM and is 110mm. The Selle Italia Turbo Matic saddle is a standout and features three suspension zones to further isolate road vibration.


Builder and distributor: Reparto Corse Bianchi Srl, 24047 Treviglio (BG), Via delle Battaglie 5
Price: L 4,750,000
Available sizes: 49-50-51-52-53-54-55-56-57-58-59-60-61-62-63 cm (center-top)
Measure of test bike: 55cm
Colors: Bianchi Celeste, blue marine, matte blue, white pearl, metallic red, red-black fade, green fade to Austrian blue, Ferrari red and matte violet
Total Weight: 9.950 kg
Front Wheel Weight: 1.315 kg
Rear Wheel Weight: 1.795 kg
Tubing: Oria Cromovan, Tig welded
Fork: Oria Cromovan uncrown
Shifters: Shimano Dura Ace Dual Control
Front derailleur: Shimano Dura Ace
Rear derailleur: Shimano Dura Ace
Chain: Shimano HG
Crank: Shimano Dura Ace 1993, 53-39 teeth, 170mm
Bottom bracket: Shimano Dura Ace cartridge
Freewheel: Shimano Dura Ace 8v: 12-13-14-15-16-17-19-21
Hubs: Shimano Dura Ace, 32 hole
Spokes: Ace stainless 2.0/1.8/2.0mm, 3x
Rims: FiR Tour hard anodized
Tires: Michelin Hi Lite Supercomp HD 700x20
Brakes: Shimano Dura Ace
Pedals: LOOK PM 76
Headset: Shimano Dura Ace
Seatpost: Shimano Dura Ace
Saddle: Selle Italia Turbo Matic
Stem: ITM 110mm
Handlebar: ITM Italia Pro, 42cm
Accessories: Elite water bottle cage, bottle

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