Here is the review from Cycling News - you can read on site by clicking this link.
We’re big fans of the hand positions and wrist comfort of Coefficient’s radical-looking AR (All Road) gravel bar and we’ve been waiting patiently to get our hands on the futuristic RR (Road Race) bar ever since we saw prototypes.
We're happy to say it didn't disappoint, so if you can afford the premium pricing, it’s a great combination of rule-bending aerodynamics, advanced ergonomics and accessory mount convenience with an excellent level of detailing throughout.
While the principles and angles behind the 12-degree back- and 15-degree down swept top geometry are shared with the AR, the RR is very different in design. For a start, that top section is a fat/flat aero shape, not a tapered bulge. The forward kink is extended into a projecting bridge which houses a switchable GPS chuck on the top side and an optional bolt-in GoPro/light mount on the underside. The extension is also profiled to cradle your thumbs and create a comfortable and secure ‘mini aero bar’ forward hand position. As it’s part of the bar (not an add-on) it also neatly sidesteps a lot of the restrictions that outlaw similar bolt-on solutions, and make the RR race useable for road racing and draft legal triathlon.
Aerodynamics are further enhanced by fully internal cable routing (guide tubes are provided to help with the tortuous threading process) to keep everything tucked away. There are ports for extra satellite shifters for Di2 setups and there’s a notch below the brake clamps for extra sprint grip when you’re in the drops. The actual drop of the bar is 7mm deeper than the AR bars at 127mm and the lower section is also more flared at 7 degrees. Add in the bridge section and that makes it 80g heavier too but that includes the GoPro and GPS mounts that would normally add close to that.
Despite the various cut-outs, the bar still passes all the relevant standards for off-road as well as on-road use too, so you can get your gRRavel on with it too.
For something as funky looking as the RR bars, it’s remarkable how ‘right’ they feel straight away. OK so we’ve got previous form from the AR but the flatter profile actually feels more natural than those big domes. The back and down-swept (which Coefficient calls ‘Swope’) shape rolls wrists down and tucks elbows in exactly the same way as they tend to when you’re trying to gurn a gear round on the tops too, but it does so completely comfortably. The fact reach increases as you move inboard feels totally natural too and the thumb loops make the extended ‘puppy paws’ position totally secure even when riding one-handed. There’s just enough room for big fists not to feel cramped either.
Position on the hoods is the same as a standard bar and the flare boosts stability when you’re down into the drops. We noticed the thumb notches a lot more than on the AR too just because we tend to tuck deeper descending on the road and that’s going to be even more of a bonus for riders with small hands. The RR bars do feel more solid than the notably ‘floaty’ AR, with more vibration on rough surfaces, but they’re certainly not a punishing bar over longer distances. The only thing that might niggle is that while there's a Bar Fly insert for almost any computer, there’s no independent angle adjustment of mount compared to the bar if you like a bit of lift on your LCD display.
We’ve used all sorts of clip/bolt-on aero bars over the years to try and get some aero and comfort advantages for speed and distance work but never dropped into a ‘Fast Forward’ position as easily as we did on the RR. The fact it's race legal and totally integrated into a really detailed lightweight bar that naturally tucks you into a very comfortable, but also aero efficient position with extra descending security is a total win. Add the universal GPS integration and optional light/camera mount and while you can’t ignore the cost, it’s easy to justify considering the amount of gains Coefficient have packed into this bar.