Pro Stealth Evo Road Stem-Bar

The Stealth Evo is a one-piece carbon monocoque bar and stem combination produced by Shimano’s subsidiary company, Pro. It has been seen fitted to the bikes of pro-riders such as Michael Rassmusen, during his ill fated 2007 Tour de France, and recently by Robert Gesink, the 3 times white jersey winner of the Tour of California.

The Stealth Evo is available in size options of 42 or 44 cm width, and extensions from 90 to 130 mm in 10 mm increments. There are two colour options of carbon black or white lacquered finish, and a quoted weight of 350g for the 42cm / 90 mm set.

Pro say the main advantages of the one-piece system are lower weight, increased stiffness and the ability to improve aerodynamics across the whole of the bar. There are safety benefits too - there are no stress risers at the stem / bar junction, and also there is no risk of incorrect torque settings or loosening of stem bolts at the bars.

The disadvantages are in getting the fit right, as you have no rotational adjustment of the bars; but Pro say that a lot of testing was done to optimise this position before production, so hopefully most people will find them comfortable. You clearly cannot change your stem length without having to change the bars too, but if you are happy and settled with the measurements you need then this should not be an issue.

Tested here was the 44 cm width with 110 mm extension in black carbon finish.

The finish of the bars is excellent; the lacquer has a high gloss with the white and silver graphics under the clearcoat. There is a roughened section where the shifters mount to prevent them slipping, and useful graduation marks to make setting the shifters at the same level easy.

Another nice touch is the slight increase in diameter of the top straight section of the bars at the point that they meet the bends; this defines where to wrap the bar tape up to, and means the tape flows seamlessly onto the carbon tops without a ridge, which not only looks clean but feels comfortable.

Underneath there are two carbon tubes either side to route the brake and gear cables, giving them compatibility with Campagnolo, SRAM and the new 2009 Shimano shifters.

In action, the first thing that becomes apparent is how comfortable they are. The wide flat profile of the tops gives lots of hand position options, but also gives them a distinct type of flex to that of a separate bar and stem. This flex does a noticeable job of calming road buzz whilst at the same time feeling stiff and sharp when pulling hard on climbs or sprints and precise into corners. There are indentations behind the shifters for your palms to rest in, which adds to the comfort when cruising on the hoods.

The optimised rotational position of the bars was, as Pro predicted, just right, for me at least.

The ergo bend of drops felt natural when moving down for corners and sprints, and was an easy reach to the brake levers. There was also no interference with my forearms when swinging the bike around in a sprint.

Before starting this test I felt somewhat sceptical; carbon stems have not previously impressed me. The Stealth Evos therefore came as a welcome surprise, stiff where they need to be, yet very forgiving over rough roads. The streamline shape and high quality finish make a very expensive looking product that shows a lot of attention to detail in its design.

Verdict

This is a stiff, light and comfortable bar/stem combination that looks as good as it rides. However, the lack of adjustability may put some potential purchasers off.