2012 BH Ultralight RED Assault
Not satisfied with simply creating lightweight bikes, BH Bikes set out to create the ultimate in lightweight bikes that also provides the ultimate in ride characteristics. After all, what does it matter if a bike is lightweight or stiff if it doesn’t ride well enough to be enjoyable all day... day after day?
Our Ultralight is not just light- with a sub 750gm weight for a painted 56cm frame, it is the lightest production frameset in the world and still exceeds the benchmarks of all the major world class brands. Climbing and sprinting have never felt better or easier- with such an amazing stiffness to weight ratio, acceleration in or out of the saddle is instantaneous.
Some might call our pursuit a bit “obsessive”, but it’s obsession to details that makes a BH, a BH.
Built from the inside, out
The Ultralight is built using a proprietary hollow core molding technology that sets the bar well above everything else that’s out there. Other high-end brands utilize previous generation molding techniques, but we’ve taken our molding technology to the next level of development to produce a frame that is unmatched in nearly every conceivable category.
The quality of the frame that exits the mold is near perfection inside and out, requiring little to no finish work prior to painting. It’s a shame we have to paint them at all. Other frames require hours of work after they come out of the molds, filling the voids and imperfections with epoxy filler which not only adds weight but can also compromise strength and stiffness in critical areas. Our hollow core internal molding technology produces a much lighter and stiffer frame because there is less material required to fill imperfections. This also produces a better ride because an ultra precise carbon layup can be optimized and tuned to provide the perfect feel without needing to worry about adding extra material.
The Ultralight requires less material to achieve target stiffness numbers - meaning a lighter frame with greater stiffness and much higher quality structures. All of this combines to produce a frame that goes above and beyond the engineering to create a bike that is much greater than the sum of its parts. It’s a ride that defies logic in its ability to deliver stiffness, precision, and superior ride quality in a frame that weighs 100 grams less than the water bottle on your down tube.
Pressure and Control
All Carbon bikes are not created equal. A nice looking frame on the outside does not tell the story of what’s going on inside. Without giving away too many secrets, we can tell you a little bit about how carbon frames are molded and what sets the Ultralight apart;
Traditional molding is done with standard polybag bladders. Basically, plastic tubes (similar in material to a plastic zipper sandwich bag) are placed inside the frame and inflated with pressure, while the carbon frame is in the mold and being heated. The pressure from the polybags pushes the carbon into the mold, creating pressure from the inside that results in the material following the form of the mold and creating the final shape of the carbon frame. This is how the vast majority of carbon frames are made and there is nothing wrong with it- it is simply not a very precise process. Pressure may not be constant in all areas, resulting in internal wrinkles and weak spots that require the manufactures to compensate for this with the use of more material in key areas.
Some of the more advanced companies with lighter frames in the market go one step further and use pre-shaped bladders (the internal bladders are made to the shape of the actual internal structure). This method is better, as it helps eliminate wrinkles, but there is still a possibility of inconsistent pressure in areas of the frame.
Our system goes well beyond all of this and eliminates the possibility of inconsistent pressures, provides the highest levels of compaction, and overall better control over the entire structure. The other key part of this is that we also have greater control over each of the individual carbon layups that go into each frame. This is another attention to detail item that sets the best apart from the rest. The “kitting” of composites is more on par with making a precision road fork layup, where tuning is critical to the ride, and strength is paramount. With the Ultralight, or any of BH’s top end models, it is not a matter of taking sheets of mid modulus composites and placing them at 45 degree angles in the mold like many other manufacturers. A ton of testing goes into exactly which composites are needed in each location and what type is to be used to optimize the frame. So, although it makes for somewhat fascinating reading to throw out material names and quote crazy high pressures for marketing purposes, the real magic happens in product development. It’s a result of the engineering, testing, and the “obsessive” drive to devote the time, effort and high cost involved with developing the layup structures that use all the best materials available in just the right places that creates a truly Ultralight frame with no rider weight limit, incredible climbing nature, cornering and descending manners, and a ride feel that makes you wish the ride would never end.
How we got there
In the creation of the Ultralight, we didn’t just rely on FEA programs or engineering data alone- we tested the frames in the real world with real riders. We built numerous versions of the frame, each with a slightly different layup schedule- producing more stiffness, less stiffness and ultimately the right stiffness. We changed the layup and the materials until we were happy with the ride characteristics as much as the test data. Though test data is not the only thing we look at, we do spend a lot of time crunching the numbers and comparing them to those of the other premium brands in the peloton. We’ve taken the industry leading performance of the G5 and ramped it up to create the ultimate, no-compromise racing platform. The end result is a frame that actually lives up to the words “laterally stiff, yet vertically compliant”.
Using a custom blend of the finest carbon from Toray, we were able to produce a frame that not only beats our previous best numbers for weight and stiffness, but also rides incredibly well for hours and hours (and days) on end. This level of commitment to testing- both in the lab and on the road- is expensive and time consuming, but when you are working to create perfection, nothing else will do.
Geometry: Fit and Handling
Weight alone should never be the deciding factor when selecting a bike. A low weight looks great on paper, in magazine reviews and catalog specs, but weight means nothing if the bike doesn’t fit and handle confidently in all situations. This is one of the many areas where the Ultralight really shines. Being a Spanish bike company from the Southern Pyrenees, we are quite proud of the fact that some of the most famous climbs in the world are in our own backyard. It is also no surprise that BH Bikes has a long history of building incredible race winning bikes for some of the world’s greatest climbers. It goes without saying, just as we have the steepest climbs, we also have some of the world’s most exciting descents. This heritage has helped us develop bikes that make you feel like a hero on the climbs while keeping your heart rate intact on the way down. How do we do this? The Ultralight features shorter than average 402mm chainstays. These are not the cookie cutter 410-415mm stays found on most high volume production bikes. Combined with an ever so slightly slacker seat angle (about ½ degree), the rear wheel is much more tucked in under the rider allowing for immediate acceleration and a connected feel to the bike not found with other brands. The result of this design is a slightly shorter wheelbase as well. We counter this with a ½ degree more relaxed head angle and precisely tuned 300 gram fork to create one of the most stable feeling, yet nimble handling bikes in the peloton. In addition to tuning the handling, the fit has been developed through decades of fit experience with riders of all levels. The Ultralight is offered in 6 frame sizes with individualized geometry, frame stiffness, and ride tuning per size.
Technology that doesn’t just stop at the frame
To develop our new frame design with the incredibly high stiffness goals that we set at the beginning of the project, we needed something more in the way of component design to achieve our goal of building the ultimate frame. The result was an over 2 year development project with FSA to develop the future of frame, bottom bracket, and crank design. Combining the best features of BB30 and Pressfit 86, we created an entirely better way to manufacture high performance frames. BB386EVO uses a wider 86.5mm bottom bracket shell width and a 30mm crank spindle to achieve frame and crankset stiffness numbers that exceeded expectations. The wider and taller bottom bracket shell size allows for more material at the area of the frame that benefits the most from it. This means that the chainstays can be taller, and the seat tube and down tube can be larger where they meet the BB, increasing the stiffness of the entire rear of the frame significantly. This also allows room for the increasingly popular wider rim sizes being ridden in the peloton. The all carbon bottom bracket shell is lighter and stiffer as well, allowing us to create a sub 750 gram 56cm frame. Not only is the BB386EVO system a dramatic improvement in bottom bracket technology, it’s also adaptable to the vast majority of cranksets. Larger bearings fully housed within the frame create a stiffer platform, as well as extended bearing life. The cross compatibility with multiple crank designs gives riders more drivetrain options. It’s not just a better bottom bracket and crankset design- it’s a significantly better frame design as well.