BMC Timemachine TMR01
Rules. If ever there was a stickler for them it's the UCI. Some are questionable, but we do approve of it's TdF bikes ruling that not only do bikes have to conform to UCI standards but must also be available to purchase.
This means that we've got some very tidy looking bikes on the high street. One of the first being BMC's new carbon road aero offering - the TMR01.
Using truncated aerofoil down and seat tubing, it's lineage can be traced directly back to the TM01, BMC's time trial machine. These abruptly finished teardrop shapes not only meet with the UCI 3:1 regulation but should cut through the air pretty sharply, and if nothing else reduce the side profile exposed to cross winds (angle of yaw).
Super clean front end
But, plenty of factories seem able to create aero profiles, it's the uber sleek front end we're most excited about; it's one of the cleanest out there. The boxed in cabling is the stuff mechanical engineers dream of; a simple yet effective solution.
Unlike other brands that have tried a similar concept, but fallen foul of the UCI fairing regulation, BMC appear to have side step this rule by squeezing it all into the 80mm allowed for tube size.
Aero is key
BMC haven't stopped there in the quest for speed. Along with hiding the Dura Ace Di2 battery from the wind in the seatpost, fully integrating cables and tucking the rear brake inside the chainstays, it's also applied the same ‘Tripwire' concept used on the TM01, which breaks up the air around the leading edges of TMR01.
Tidy lines continue
All this slipperiness BMC says adds up to a saving of 28watts at 50kph frontal wind against the SLR01 - certainly not to be sniffed at.
Weighing more than the aforementioned SLR01, the 1040g frame may not appeal to out and out climbers, but if you're the kind of rider seeking solo breakaways, a la Philip Gilbert, then it's well worth a closer look.
Pricing options TBC
UCI 3:1 Rule
The UCI 3:1 rule in essence the ratio of any given tubes vital statistics, usually the depth compared to width. It's worth remembering that all tubing also has minimum and maximum dimensions to conform to as well. The maximum transverse dimension is 80mm. So in order to meet the 3:1 rule in particular the corresponding dimension can be no less than 26.6mm (80mm divided 3). The minimum aspect to major frame elements is 25mm. The smaller elements of the frame; seat stays, chain stays and forks are allowed to have smaller dimensions at 10mm.
This article was first published in the August 16 issue of Cycling Weekly. You can also read our magazines on Zinio and download from the Apple store.