My eyes can gloss over when another bike brand claims the usual “lighter, stiffer, faster” about a new road race bike. But Colnago didn’t just polish an already successful design. It started over, and the resulting V5Rs touts figures representing significant improvements.
Colnago has been cooperating with the UAE Team Emirates WorldTour professional cycling team since a corporation in Abu Dhabi acquired the bike brand in 2020. Colnago staffers explained the multiple series of back-and-forth discussions and tests that helped create the new V5Rs. And as you might expect from a team that seems to have unlimited financial resources, Colnago was able to drop significant weight from the new bike.
The V5Rs comes on the heels of the Colnago Y1Rs, a striking aero road bike without a traditional seat tube. The V5Rs is more of an all-around or climbing road race machine.
What’s New on the Colnago V5Rs
Lighter, of Course
Road racing brands dare not offer a new “climbing” bike without dropping weight. In this case, Colnago didn’t just drop a few percentage points of mass — it went big.
After being the first major brand to use carbon fiber in bikes, Colnago has made its lightest road frame yet. It claims that an unpainted frame weighs 685g in the middle 510mm size (Colnago sizes its frames differently than most). This isn’t the lightest road bike frame on the market, but it is still incredibly svelte.
This represents a 12.5% (146g) difference from the V4Rs, which is significant in the road racing world.
More Structured Internal Mandrels
Plenty of factors contributed to the weight loss without sacrificing lateral stiffness. One main difference was Colnago’s use of a more rigid mandrel instead of a “soft” mandrel.
When making a carbon fiber frame, an internal bladder is inflated to push the carbon fiber pre-preg against the metal mold from the inside to reduce voids. These internal mandrels must be pulled out of the frame after it “bakes,” so they must be soft enough to yank out of small holes in the frame.
Colnago uses a stiffer mandrel made of polypropylene. This allows more controlled mandrel shapes, especially for more intricate junctions and smaller radius angles, since the mandrels have more structure than softer materials.
The carbon fiber moves less during the curing process, retaining more of the exact fiber orientation and compaction mapped out by Finite Element Analysis (FEM) computer modeling. The new mandrels also produce a much smoother finish on the internal walls of the frame tubes.
Smaller Bottom Bracket
Colnago went back in time a bit and used a BSA bottom bracket, resisting the trend toward the bigger T47 that seems to be taking over. Colnago claims that the stiffness of the V5Rs’ bottom bracket area doesn’t need help from oversized T47 bottom brackets. Additionally, the Italian brand created a lighter seat post and specifies smaller head tube bearings in the V5Rs.
Is It More Aero?
The Colnago V5Rs bikes displayed at Sea Otter didn’t seem that visibly different from the V4Rs at first glance, so it wasn’t obvious that they were more aero.
Colnago combined the on-frame pressure sensors it used to develop the Y1Rs with Computational Fluid Dynamics (CFD) to make the V5Rs faster than the outgoing V4Rs.
Reduced Frontal Area
To slice through the air, skinny forward-facing aspects are the name of the game. Colnago did just that on the V5Rs. The head tube is smaller, especially at the top, due to a smaller bearing. It also sports a “nosecone” profile facing forward.
The fork blades are also thinner, as is the new seat post. The seat post looked drastically different: It’s way skinnier than the previous D-shaped unit.
Colnago claims these efforts save about 9 W at 0 degrees of yaw with a rider aboard at 50 kph, compared to the V4Rs. The same weighted difference exists for up to -10 degrees of yaw.
But What About Stiffness?
Being lighter or more aero doesn’t matter if the bike doesn’t hold up to the lateral and torsional forces a professional rider can inflict on the frame and fork. Sprinting, climbing, and cornering at speed exaggerate any lack of off-plane rigidity on a road race bike.
Forces on the Bike, for Real
Colnago studied the off-axis forces produced by sprinting and seated climbing during the development of the V5Rs. It deduced that sprinting especially stresses the front triangle of the frame, while seated climbing stresses the rear triangle.
Sprinting involves placing high loads on both the handlebars and bottom bracket at oscillating angles of camber relative to the frame’s plane. Seated riding only places loads in the same plane of the front triangle.
Aero vs. Lateral and Torsional Stiffness
Reducing frontal area can negatively affect out-of-plane stiffness since the tubes’ lateral cross-section is usually thinner. Colnago subjected frames to stress tests to analyze and engineer a way to maintain power and handling-conserving stiffness.
Colnago deduced that the frame joints at the seat tube required optimization to maintain the standards of the most powerful cycling professionals. It massaged the carbon layup into specific shapes at the tube junctions and raised the seat stays on the seat tube to maintain lateral and torsional rigidity. Colnago also refined the tube shapes, in general, to eke out every bit of efficiency.
Geometry
Colnago knows it has a good thing in the geometry and associated handling of the V4Rs. It kept much of this intact on the V5Rs, but made subtle adjustments based on current professional racing.
The head tube and seat tube are slightly steeper. These accommodate the more aggressive forward position that current WorldTour riders favor while also sharpening the handling a touch. Colnago employs two different fork rakes so that the trail of the bike with larger, modern tires stays more consistent across the seven sizes (510-570 mm) it offers.
Colors
The impressive numbers are matched by Colnago’s well-known jaw-dropping paint schemes. Of course, the UAE Team Emirates color scheme is available, as is a World Champion version with the trademark rainbow colors against a pure white background. Colnago offers a stealthy flat black for those who prefer an understated look.
But what did it for me was the pearly white-and-blue of the women’s UAE Team ADQ WorldTour squad. It was clean, with a hint of flash.
Final Word on Tadej Pogačar’s New WorldTour Weapon
All the hype and statistics about the V5Rs don’t matter if three-time Tour de France winner and current World Champion Tadej Pogačar refuses to ride the bike. But Colnago staffers, both from Italy and Abu Dhabi, reassured us that the current darling of road racing approves of the new V5Rs and will be racing it in late April. Of course, a bike of this caliber requires a thick wallet. Here is a sampling of pricing:
- Frame kit: $6,250
- Shimano Dura-Ace/ENVE build: $16,500
- Shimano Ultegra build: $11,750
Save your money, kids!
Read the full article here
