Cyclist technology check: In the latest Cyclist technology check, aero racers under €3.500 are put to the test. In addition to the BMC timemachine TMR02 (€2.899), the Boardman AiR 9.2 (€3.299) and the Bottechia T1 Tourmalet (€3.499) also have to prove themselves - the entire test can of course be read in Cyclist 3/15.
About the wheel
All of the bikes in BMC's aero fleet carry variations of the timemachine moniker in their names, whether it's the TM triathlon bike or the TMR aero road bike. All models descend from the original TM01 time trial bike and these influences are clearly visible in the TMR01 and TMR02 duo – we tested the latter with Shimano Ultegra kit (it's also available with the 105 groupset, while the TMR01 comes with Ultegra, Ultegra Di2 or Dura-Ace Di2 is available).
Frame
The TMR02 has little in common with conventional frame shapes, but that's what you would expect from a UCI-compliant triathlon bike. With its horizontal top tube, deep down tube and straight edges, the TMR02 conveys only one thing at first sight: pure speed on the straight. The frame is peppered with aero optimizations that BMC has dubbed SubA. This includes the so-called Tripwire technology, with which turbulence is generated at the wind edges, which optimizes the airflow (similar to a golf ball), and the teardrop-shaped tube structures, which end smooth rather than pointed, which saves weight and increases rigidity . Out on the road, the bike makes no secret of the fact that it wants to be ridden fast – very fast. It literally persuades the driver to get into the perfect position. The geometry is the same for all models as for the Primus TMR01, the difference lies in the layering of the carbon and the lack of an integrated front brake.
Components
With Shimano's Ultegra components, BMC has equipped its bike with a groupset that can be found on many models in this price range. The difference to other groupsets is clear to anyone who has ridden them: the Ultegra is lighter and shifts smoother than the 105s, but cannot boast of the perfection of the Dura-Ace. But what you don't know doesn't make you hot, so you won't miss anything when you ride the Ultegra, because it's a fantastic group. The aero integration of the attachments is evident in the rear brake, which is mounted on the chainstay and behind the bottom bracket, and in the very practical seat post clamp. However, the over-wide 44 cm handlebar is an odd choice that unnecessarily increases drag.
Wheels
The Shimano RS31 wheels are the area that has been hit hardest by inevitable austerity measures. However, that doesn't mean they're worthless. With their 30 mm high rims, they are marketed as wheels with aerodynamic advantages, but compared to "real" aero wheels, which also like to come up with 90 mm, this is practically nothing. On the road they feel stable and relatively stiff, and the 25mm wide Continental Ultrasport 2 tires are solid. However, swapping those wheels out for a high-end carbon wheelset would instantly transform this bike into a serious time trial machine.
driving behavior
The TMR02 shows its strengths best when the driver sits low, elbows together and legs give full power. That's what an aero road bike is all about. It is only logical that the BMC behaves best when it is ridden in this way. Stepping out of the saddle and throwing it left to right in a sprint, the TMR02 feels a little sluggish due to the raised, horizontal top tube and resulting large front triangle. However, the feedback from the road is outstanding and the handling accordingly inspires confidence. At no time do you feel detached from the bike or the road as a driver.
Deep down tube
An increasingly common feature on aero racers is the deeper down tube. The BMC is the best example of this. You can also see it on the Bottecchia, but not quite as pronounced. The idea behind this is that the wheel, tire and frame should function as one object and are therefore more aerodynamic as a unit. The connection to the head tube remains unaffected, as does the geometry, but the protruding lower part of the down tube curves around the fork crown to bring it closer to the front wheel. At the narrowest point, the down tube of the TMR02 even has a minimal indentation. You can't get much closer to the wheel.
Conclusion
Peppered with numerous aero features, such as tube shapes for optimized airflow, the TMR02 conveys a confidence-inspiring driving experience.
