From now on, data transmission from all SRM measuring cranks, including the speed signal, to the "Powercontrol" computer will be wireless. This is made possible by the so-called "ANT+Sport Protocol" transmission standard. The new "wireless" version has several advantages over the old cable technology: the system can be installed in ten minutes with the crankset, watt sensor, handlebar bracket and a speed sensor integrated in the quick release. The sensors then have to be activated and paired with the "Powercontrol", which worked on the second attempt. The watt sensor now sits firmly between the bottom bracket and the gear cable guide and can no longer slip, as happened time and again with the old sensor with rubber mount. Data loss due to lack of contact is therefore almost impossible. And: the bike's appearance is retained thanks to the lack of cables. The SRM developers have also finally added an altimeter to the new "Powercontrol VI" computer, which allows altitude profiles to be integrated into the evaluation diagrams.
For an extensive test at the TOUR-Trans-Austria, we chose the Dura-Ace-compatible compact version of the Powermeter. We mounted the system on a 2009 "Roubaix SL2" from Specialized, already equipped with the new Dura-Ace groupset from Shimano. Initial findings: The SRM crankset could be easily shifted with the new lever, the new chain did not cause any noticeable noise on the old chainrings and moved easily from the small to the large chainring and vice versa when shifting. During our test, the lithium-ion battery in the "box" wanted fresh power after three stages with a net riding time of just under 18 hours, whereby the battery status can be constantly checked at the touch of a button.
Once during the Trans-Austria week, the power indicator on the display remained blank for more than an hour. The reason for this could not be determined. The supplied software version 6.40.07 does not appear to be free of bugs, as the data transfer from the computer to the computer did not always work straight away; in addition, some menus were graphically incomplete.
PLUS: easy mounting; power sensor is non-slip; integrated altimeter
MINUS: High price; software not error-free; operation of the software not very intuitive
Reference/Info: Schoberer Rad Messtechnik SRM, phone 02461/69123-0, www.srm.de
Price: 3,510.50 Euro
Photos: Uwe Geißler
