The new frame VR-R-268 is a product of the present trend in pro bike racing.
So here few points.
#1. Aerodynamics is the major element that pro racer looks for. The pro riders know their CdA and how to decrease it.
The more aero you are the faster you go for the same power.
#2 CdA is the quantitative measurement of aerodynamic drag. The "A" is the frontal area of both the rider and the bike presented to the wind in the direction you travel. You can decrease the "riders part" of the A by being on the drops instead of seating up. VB has paid a lot of attention to this part.
#3 Cd is the coefficient of drag. For example if you place a flat disk in a wind tunnel and make the A=1 the surface area will be 1 but the force the wind actually exert on the disk is a little higher let's say 1.15. So the CdA will be 1 x 1.15= 1.15. Now instead of flat disk, place cone with the tip forward and a front area the same A=1, but now the coefficient of drag will be far lower so the total CdA will be far lower (that is the reason why bullets for example are not flat at the front). Here VB has done a superb job in decreasing the Cd.
#4 VB aerobike like the VR-R-268 is aimed at decreasing the Cd even if in some cases you may have a little weight penalty. Lower seat stays with a flat top, aero seat-post, kamm tail the downtube and a very nice combination of the seat-tube and rear wheel-tires to make the air flow smooth. The seat-post in the present bikes is more exposed comparing with years past so an aero seat-post is a must. VB has done a great job here.
5. The rider also has a "A" and "Cd". The "A" is obvious the more down the rider is the smaller the "A" but the "Cd" is not as clear, racer used to adopt the "puppy paws" position (which now is ban)etc. The point here is that the position on the bike has changed and VB has done everything possible to allow this change. The seat is more forward as much as you can without braking the UCI rules "The tip of the saddle shall be a minimum of 50 mm to the rear of a vertical plane passing through the bottom bracket spindle." This forward position allow to open the leg body angle so you do not hit your body when you pedal. VB zero-offset seat-post goes along with this trend. Also rider use short saddles to go around this rule.
6. Along with #5 the back is flat and when racers place hand on the hood but keep the forearms flat (the most aero position) it is important than the angle between arms and forearms is 90 degrees or less so the distance between between brake hood and saddle is smaller than in the past, so you want a short top tube. To accomplish this aspect, pro racers are choosing smaller bikes than before. VB has a small frame and a 9 cm stem as the smallest. VB is ok here, even it could have offered an 8cm stem.
7. Components are also part of this trend. Cranks are shorter that were in the past, for example Tadej (176 cm) is using a 165 mm crank, Filippo Ganna (193 cm) iirc use a 170 crank for the hour record, MVP (184 cm) is in 172.5. The smaller cranks offer aero advantage, and also you are working in the area where mechanically you are stronger. Of course you need gears that you can spin. VB is compatible with all the component manufactures.
6. In pro racing mixing areas with good asphalt with unpaved or gravel road are becoming very common. Having a frame that accepts different width tires is important so you do not need to have a different bike for each terrain. VB has done a great job here allowing as to use tires up to 32. Many other frame manufactures have aero bike but basically designed around the 28 mm now standard in road racing. With this VB frame you can have 2 sets of wheels like a road with 28mm tire and wider rim wheel with a 32 mm gravel tire and if you want to do some rough single track gravel you just change the wheel.
7. Aerodynamics are important in flat terrain but also during climbing when you have a head wind, or the grade is not very steep, having you body down help, you can feel it on your legs and also if you have the correct setup, you may see the CdA not increasing. Few of the pro's climb with the forearm flat on the top of the handlebar.
7. The only part the VB has not touch for aerodynamics is the flared handlebars. The UCI set also rules there and a small flare would be OK. This rules changed in Jan 2024 included the brake levers angles and it may change again.
In summary VB offers a high quality frame with almost all the features that are trending in pro racing, before I got it I look around and I could not find one that I could place a check mark in each of the features I wanted with the exception of VB-R 264.
I have been trying to explain why the the VB-R-268 is my choice. VB has many frames with different features and for many of us may be better. I have more than a month since I start to ride, which I do everyday, in different terrains, with a 28 tire you can do most of the gravel. Sometime next year I will get a "gravel" wheel to do single track.
Chris has been great with fast replies to all my questions, so to have a good online service is also important part of the frame. I am very happy with this bike.
Note: I got and extra seat-post and seat-post clamp when I placed the order for the frame, I like to have them as spare and the price was very reasonable. The seat-post seem very solid and very nicely made so most likely I will never need them.
