Renthal Carbon Fatbar Lite - First Look

FIRST LOOK

Renthal Fatbar Lite Carbon

WORDS & STILL PHOTOS: Matt Wragg

When Renthal entered the market for mountain bike handlebars they didn't follow the conventional route. On the moto side their components have been developed from racing for nearly 50 years now and are well-known for having barely an excess gram to be found. With this long history in motocross, they understand better than most that small margins can make all the difference. Yet their Fatbar weighed in at 360g, noticeably heavier than most of the competition. Their reason for this? That was how heavy it needed to be, to be as strong as they wanted it to be.

We visited their factory near Manchester in England at the start of 2012 to take a look at their product development and production. Looking at their testing rigs first hand, it was readily apparent how thorough they are in approaching something like this. As we watched one of their bars go through the cycles on the test rig, Ian Collins, their MTB marketing manager, admitted they had put their competitor's bars through the same tests, just so they could know where they stood in comparison. Prodding him on which bars were good and which bad, he remained silent. The one thing he let slip: "You need to be careful buying very light, carbon handlebars..." So how comes now, just under two years later, Renthal are launching the lightest carbon handlebar in its class?

The First Carbon Bar

Catching up with Ian again as they announce the carbon version of their trail handlebar, the Fatbar Lite, he feels it is something they had to do. "It wasn't really a decision for us, it was a must. We're obviously a premium-level brand and if you don't have a carbon product in your lineup, then you're not fulfilling what the brand can do."


Details:

• Purpose: Trail/All-mountain/Enduro
• Uni-directional carbon fibre lay-up
• 740mm wide
• 7° back sweep, 5° up sweep
• Available in 10mm, 20mm, 30mm and 40mm rise
• Weight: 180g (for all rises)
• MSRP: $159.99
• Available now




This is new territory for Renthal. In all those years, they have never before produced a carbon handlebar. In fact they have never produced a handlebar made of anything other than aluminium, the demand simply isn't there with motocross. To work with carbon is a very special skill, to understand how to lay-up the right fibres to create precise qualities of strength and stiffness takes years to master. Ian is utterly candid about this, "If we wanted to do it in-house, then we'd be looking at do this in five or ten years' time when the expertise level had reached where it needed to be. We had to decide who to use a partner to manufacture it. Initially we wanted to keep it in the UK, we spoke to a few vendors, a few manufacturers, but they were all doing small production runs, looking to make carbon products for Formula One and other sorts of motorsport. They were typically falling behind Asia in terms of technology but also, because they were geared up for doing small production runs, the capacity for production just wasn't there for. We're a worldwide company, we sell a lot of handlebars. So the decision was made the decision to go to Taiwan, and we partnered with who we feel is the very best carbon handlebar manufacturer in the world."

Pre-prototype Testing

However, Ian is clear that the new handlebar is not an off-the-shelf job. To start the development they began testing existing handlebars because they wanted to understand how the bar should feel, how stiff or flexible it should be. To do this, they put together a group of four riders and made them ride a loop again and again, with masked handlebars on their bikes so they had no idea what bars they were riding with each time. In the test was Renthals own Fatbar Lite and a selection from their competitors, both aluminium and carbon. They scored them on climbing, descending and cornering and in each of those categories they rated the bar on comfort, control and stiffness. As Ian explains, "We wanted to identify a bar that had the right level of control, but equally had the right level of comfort, which is very important. From that test, the majority favourite bar was the Fatbar Lite aluminium handlebar, which was great news for us, it rated highly in all the categories. From this testing, we wanted to make a carbon handlebar that felt like the aluminium handlebar."

With the data in from the testing the next step was to gain a deeper understanding of the stresses that handlebars go through out on the trail. For this stage they used strain gauges fitted to handlebars and took them out on downhill and cross-country tracks. Testing was done by a broad mix of riders, of all shapes and sizes, from top-level professionals all the way down to beginners to get data on what a handlebar could go through with a broad spectrum if different riders and different riding styles. The two main datasets from this were the peak load the bars went through and the mean load while riding. With this kind of real world information on what a handlebar goes through while riding they could match this to the desired characteristics from the first test and begin to create models of the handlebar they wanted to produce.


Keeping Form

The final step was to give the bar a shape. From the testing they established that they wanted to use the shape of their existing Fatbar Lite. As Ian explains, "We know that's a great shape. We feel that a 740mm wide bar hits the nail on the head for the majority of trail riders. We didn't want to make it wider, because if you make it wider, you need to add a lot more material to the centre. We found the majority of people were running 740, or even less, for this type of bar and by making the bar that little bit wider, those people then have to suffer having to carry a bit of extra weight that they don't need. Something we picked up on, is that the relationship of the position of the first bend to the second bend is very important. When you roll the bar, it stays very neutral. Some handlebars, if you like to roll your bars forward or back, can get a bit funky, the handling gets a bit off. Where the shape of ours is such that it remains pretty neutral when you roll them forwards or back."


While many companies are experimenting with 35mm diameter handlebars, Renthal have resolutely stuck with a standard 31.8mm diameter. In their own words, "We never like to follow fashion for the sake of fitting in with what our competitors are doing." Ian goes on to say, "We have a number of reasons for not following this latest standard. Firstly, and most importantly, when looking at the combined package of handlebar and stem, the weight is actually higher, due to the extra material needed for the stem. We have proved with the Fatbar Lite Carbon that they can be made light enough, definitely strong enough and have the right flex characteristics in 31.8mm. By offering a high performance 31.8mm carbon handlebar, the rider can gain these advantages at the cost of a handlebar only, rather than needing the stem to also be replaced. When looking at aluminium handlebars, the disadvantages of an overly stiff ride negates the use of the 35mm standard. We will only adopt a new standard if there are genuine performance advantages for the rider. In the case of 35mm, we feel that where there may be some small gains in certain areas, but when looking at the big picture, the disadvantages are too significant."

The First Prototypes

With the data and the shape from their existing bar, they could create an accurate computer model of the bar they wanted to produce. Once they had the model, it was time to pass it to their partner in Taiwan to lay-up the carbon to match the characteristics of the model. Since the 1970s, we in the West have been outsourcing our manufacturing to the Far East, and while at first it may have been for the cost, if you spend 40 or so years doing something you are going to get good at it. Really good. Today, many of the best carbon manufacturers in the world are in Taiwan, and that experience paid off for Renthal. Ian was clearly impressed with what came back, "We received the prototype back from them, and took it back to the blind field test that we did. We used the same handlebars that we used previously, but also put our carbon bar in there, and then got the riders to score the bars again on the same criteria they used the first time. We got a really positive result from that, the carbon fibre bar turned out to be the riders' favourite. So, it was job done at the first prototype, because we put all the work in before we made any handlebars at all and we had all the criteria laid out. These guys we are working with out in Taiwan are incredible, they really know their stuff. They produced a bar that was exactly to our requirements, so the first proto was absolutely bang-on."


Once Renthal had the ride qualities of the bar right, the next step was making it look right. Ian recalls, "We did go through two rounds of prototypes, because we wanted to make a cosmetic change. The oversize centre section extends all the way up to the second bend. By having that oversized centre section, you are able to tune the ride feel of the bar better than if you have a small diameter, you have more material to work with so you can tune the lay-up better. On the first prototype we didn't like the transition between the two profiles, purely as a cosmetic thing. It took a couple of goes to get the graphics how we wanted them too, but structurally, the bar hasn't changed from that first proto."


The Big Question

Of course, the inescapable question with any carbon bar is strength. Most of us have heard the horror stories about carbon bars snapping, and it wasn't so long ago Renthal themselves were warning us about the dangers of ultra light carbon handlebars. Their answer goes back to that reoccurring theme with Renthal: testing. "We are very aware that people's big fear about carbon is catastrophic failure," says Ian. "We wanted to build the handlebar as strong as possible. From the data acquisition, it's very clear that you're never going to break a carbon handlebar in normal use. Your body weight against the handlebar will never snap one, even with the weakest ones on the market, the breakages come from crashes. This means you have to build crash durability into it. We drop-tested our handlebar to the BMX test and quite a significant amount above that. We wanted to know that the handlebar, despite being so light, wasn't going to break. We have to do that because we want to produce the best components possible and you can imagine how damaging it would be to a company like Renthal if there was a breakage of our carbon bars. These are super-tough."

The Fatbar Lite Carbon is available now, and is already shipping out to Renthals distributors. MSRP $159.99. And the good news for anybody looking for something a bit wider is the Renthal are already working on a 780mm DH version of the bar, that they hope to release next year.

www.renthal.com