First Look: Renthal Fatbar Carbon

Renthal Fatbar Carbon When Renthal launched their Fatbar Carbon Lite last year, the most prominent question in the comments was, "Why aren't they doing a wider bar?" This simple answer is, they were. Renthal don't rush things though - their lock-on grips took about three years before they were ready to release them. We're quite glad Renthal didn't rush either, because if there was a list of components on a bike that you need to trust the manufacturer of, we'd argue that a carbon handlebar is at the very top of that list. Why? Because if a handlebar fails it's going to be ugly - yes, forks, frame, wheels and any other component aren't good if they fail, but a failed handlebar means you're going forwards and down, not a good direction to be heading in. Throw in the fact that you can't see damage in carbon and that any failure will probably involved sharp jagged edges, and you can see why you need to trust the company making your handlebar. So we're glad that Renthal took their sweet time before giving us the Fatbar Carbon - a product we suspect many weight-conscious downhilllers have been waiting for.

Details Intended use: Trail/all-mountain/enduro/freeride/DH Width: 780mm Rise: 10, 20, 30 and 40mm Upsweep: 5 degrees Backsweep: 7 degrees Clamping diameter: 31.8mm only Weight: 225g MSRP: $164.99 USD Available: Now

Doing their market research, Renthal discovered that there was a bigger market for the 740mm bar, so introduced that one first. If you're asking, "Why didn't they just make a longer bar and let people chop it down after?" The answer to the question is two-fold. First there is the question of weight. A longer bar means you have more leverage, so the bar needs to be built stronger to cope with that. So, following that logic through, if you make a shorter bar, you can use less material and make it lighter, as it needs to deal with smaller leverage forces.

The other question is a topic Renthal are one of the foremost proponents off - ride feel. When they develop their bars, they run blind tests with riders to determine what characteristics they want from the bar - trying to find the best combinations between comfort and stiffness for riders. If we go back to the leverage forces, the material that keeps the bar stiff is there in a precise layup to work with that amount of leverage. If you shorten the bar, you reduce the leverage and change the ride-feel of the bar, making it harsher, degrading the comfort Renthal worked hard to build into the bar. Market manager, Ian Collins, is very clear on this matter, "We don't believe you can make one bar fits all. We don't think you should make an 810mm bar and say 'well, you can cut it down to 740mm, if you want.' Yes, you can cut it down, but it isn't going to ride right."


One interesting detail with this new, longer carbon bar is that they didn't exactly match the feel of the counterpart aluminum bar, as they did with the Carbon Fatbar Light, they ended up reducing the stiffness in this bar, as they felt the switch in material required a slight change in the ride feel. "We wanted to get it as close as possible to the aluminum one, again," explains Ian. "But we knew we needed to make it a little bit softer, just because of the natural frequency of carbon. If we'd made it as stiff as the aluminum bar, it would have felt too harsh. So it is ever so slightly softer. You don't feel it in terms of steering control, but it takes that edge off, that you don't get with aluminum."

Where this bar is different to their Fatbar Light Carbon is in the crash durability. As Ian sets out, "We don't recommend people ride downhill with that bar. That's not because the bar's not strong enough to ride downhill, it's to do with crash durability. When you've got a twin crown fork you've also got a limited steering angle. If you crash, the bar can't spin out of the way and a lot of force can be generated, which is much greater than you'll ever put through it riding the bike, so we built a lot more crash durability into this handlebar. We didn't go all-out to make this lightest bar possible, we wanted to retain that crash durability too."

Riding Impressions

We've been using the Fatbar Carbon for a month or so now and the truth is we don't have much to report. While we liked the Fatbar Lite Carbon and came to accept its 740mm width, moving back to a full-sized bar did feel good. We cut our test bar down to 760mm, which is where we were running the aluminum predecessor for several years. It is worth noting that if you are going to cut a carbon bar down, you need a carbon-specific saw so you don't damage the carbon fibers with the saw blade, compromising the structure of the bar. If you have ridden the aluminum version, then this bar will feel instantly familiar - we ran that bar for so long precisely because it felt so good and that feeling and shape is still there. If anything we would say that the ride is ever so slightly nicer on the carbon bar, it did seem to damp the vibration from the trail slightly more, which helped on long, alpine descents. We're sure some of you are asking whether that slight improvement in feel is worth the $65 upcharge over the aluminum bar, and would we say no, it isn't. What's more, we're pretty sure Renthal would agree with us there. Why this bar would be worth the money is for the weight-saving. At more than 100g lighter than the aluminum version, that is a noticeable chunk of weight, especially if you consider other components looking for similar savings. You definitely won't find that kind of weight saving on the cranks, wheels or frame for that much money... Yes, it isn't cheap, but on those kind of maths it will certainly look like reasonable value for some people. What's more, Renthal are still going to offer the aluminum bar, which was good enough for Gwin and Brosnan to win World Cups on this year if you are put off by the price. For those who can afford it, the Fatbar Carbon is a perfect piece of kit.

www.renthal.com