The observant amongst us will have noticed something a little extra attached to the crank arm of the Team Lampre Merida bikes at the Tour de France this week. On the most punishing stage of the tour so far, over the pavé on stage 5, Rui Costa chose to use the new Rotor LT power cranks. A lighter power measurement system than anything we have seen before from the Spanish-based Rotor Bike Components.

The system was designed in collaboration with Team Lampre Merida when the team pushed for something that performed well and kept weight to a minimum. The power is taken from the left hand (non-drive side) crank arm and uses mathematical algorithm to give a normalised power. The Power LT has been tested in collaboration with other power meters on the market over the opening days of the Tour and it only took until stage 4 for Rui Costa to be confident that he could use it exclusively.

When a chainset is designed with a rider such as Rui Costa in mind, weight will always be a primary concern. The Power LT adds just 53g of additional weight compared to the already light 3D+ crank. Aesthetically the Power LT is not too dissimilar to the 3D+ chainsets already available from Rotor. Using the exact same drive side arm, spider and spindle. But with an evolved non-drive side to include the power sensors and transmitters.

What is fascinating for anyone who wants to use a power measurement device is the price of the Power LT. With a retail price of just £799, the Power LT looks as though it matches its competitors on price, that is until you realise that not only do you get the left crank arm but you get the whole chainset. With the Rotor POWER offering advanced levels of measurement the Power LT gives a fantastic level of technology for the price.

The chainset communicates with your existing devices using ANT+ technology, so whether it is your Garmin bike computer or if you are using ANT+ on your phone you will be able to connect directly to Strava through the mobile app.

The drawback however is that the Power LT does not offer dual power that can sometimes be found on more expensive units, so won't give a left and right power measurement independently. This is not all bad though as it is believed that normalised power allows the rider to get the information they need for training purposes. Torque Effectiveness and pedal smoothness values are recorded for the left values from the Power LT.

The Power LT is available in both 110 and 130BCD, giving the user the choice of the chainrings(available separately) Rotor produce. Which is excellent as Rotor offer such a great selection to choose from for any application you can dream up including; QXL Rings, QRings and NoQ Rings. Click here to view full range.