Last year John wrote briefly about his early impressions of the BERD spokes while piloting the Sour Bicycles Pasta Party. Due to mixing around bikes and wheels, he ended up handing them over to Kyle Klain to ride and review. After months of riding in and around Santa Fe as well as across southeast Utah during the Aquarius Huts Tour, Kyle has some thoughts to share on this unusual wheel-building option.
Why reinvent the wheel? Unlike most other parts of a bike, the wheel has remained mostly unchanged with the exception of carbon rims and disc brakes–okay, maybe aluminum spokes too. Regardless, aluminum rim + nipple + steel spokes + hub = wheel. It is a formula that has been repeated millions of times for good reason. It works. Then comes BERD, who, with the help of modern materials and a strange affection for fibrous materials, is looking to shake up that formula by replacing the steel spoke with…rope. Now, if you’re like me, if it ain’t broke, don’t fix it. Should you consider this strange and unusual newcomer for your next wheelset?
What are BERD spokes?
The long short is that BERD spokes ($8 a spoke) are a polymer fiber rope used in place of a traditional steel/aluminum spoke. BERD’s website makes some bold claims about their spokes that are above my pay grade, and instead of trying to dumb it down to my level, I asked my wife Kim, who has a Ph.D. in mechanical engineering, to help us understand the tech behind the spokes.
As Dr. Kim Klain explains:
Fiber or ‘rope’ spokes work because the spokes on a bicycle wheel are always under tension. This means that any strong, durable material, regardless of its rigidity, can be used to make a spoke (as long as it can be fashioned into the shape of a spoke, of course). BERD spokes are made from UHMWPE, a special type of polyethylene that has excellent fatigue, tensile, and impact strength while being much lighter than your typical steel spoke. UHMWPE has over three times the tensile strength (in the fiber direction) of high-strength steel according to research discussed here. It is also very resistant to abrasion and UV exposure, and when braided can offer multiple layers of failure protection. Strong, lightweight, resistant to damage – what’s not to like?
One of the biggest challenges for a spoke material is trying to accomplish multiple scenarios in a lightweight, durable package. When a wheel hits a rock or has a hard landing, the rim will deform and remove tension from the spokes at and near the impact zone. Ideally, you have a material that is stiff enough to keep the rim under tension, but flexible enough to repeatedly lose tension and rapidly re-tension. This is why steel has become the favorite material–you can draw it out thin enough to be stiff and relatively light, while durable enough to be cycled thousands of times without failure. Some alloys of aluminum can accomplish this as well, but you must be very careful in quality control. Where metal starts to lose its appeal is in its brittleness. Steel and aluminum will fatigue and when they fail, it will be rapid and typically catastrophic; i.e., a broken spoke. Compare that to a braided material that inherently is much more flexible and can fatigue significantly longer; the longevity of the BERD spokes really stands out as an upgrade.
The spokes can be used on nearly any hub that accepts j-bend spokes. The spoke is “pulled” through the spoke hole and held in place not with a knot but by inserting a small spoke holding rod into the loop at the end of the spoke. This rod is made from the same material as the spokes, with a hardening agent applied. When this rod is inserted into the loop of the spoke, there isn’t enough real estate in the hub spoke hole for the spoke to pull through. No splicing tool or metal spacer is involved.
Berd explained this process in an email to us:
“On the rim side of the spoke “sleeve” is a short threaded rod that is inserted into the middle of the rope. A small amount of a fastening agent (glue) is used to hold the threaded rod in place when it is not under tension but the real “grab” is achieved by the “Chinese Finger Trap” forces that are possible with a braided rope. The more tension that is applied, the stronger the bond. This is where we hold some of our patents and we even have a grant from the National Science Foundation for the work that we have done to develop this technology. This threaded metal rod is the exact same interface as a standard spoke so there is no proprietary connection with the rim.
While we do use traditional nipples, we do require that wheels are built with 16mm Double Square nipples. Because Berd spokes stretch during the building process you need somewhere for that metal rod to go and you don’t want it hanging out the top of the spoke nipple. We require 16mm nipples because our spoke calculator is formatted to account with this length. As your previous article mentioned, the spoke calculation process is very finite and important to do correctly.”
If this all sounds confusing, we have photos from the wheel builders at BTI that help explain. The biggest con in this regard is relearning your wheel building and being very specific about spoke length measurements.
And if you’re worried that the white spokes will look goofy on your earth-toned wonderbike (looking at you John and Josh), BERD offers spoke coloring kits that you can apply to the spokes for a wide-ranging palette you can mix and match that would be the envy of the anodizing department at Industry Nine.
Coincidentally, my previous wheelset was a near-perfect comparison: Industry Nine hubs laced to Stan’s Arch MK3 rims with DT Swiss double-butted spokes. Once I realized this, I also matched the tires with what I had ridden in the previous year. For good measure, I weighed the wheels before adding discs, cassette, and tires. The BERD-spoked setup weighed in at a sprightly 1,462g. By comparison, the DT-spoked wheelset came in at a heavier 1,720g. I don’t know about you, but over half a pound seems like a substantial weight savings.
The front wheel was clad with Maxxis Dissector 29×2.4 Maxxterra and the rear with Maxxis Rekon 29×2.4 in Dual Compound. For a hardtail I always run inserts on the rear wheel, even if the tires aren’t on the lighter side. The added peace of mind and ability to ride out poor line choices is worth the minor weight penalty. In this case, I ran the rear with the Tannus liner, which adds another 120g but offers rim and sidewall protection. It’s also a helluva lot easier to install and if you have ever fought a Cushcore, then you know this is a real selling point.
Setup was just like any other modern tubeless install–tire on rim, sealant injected through valve, and a quick hit with the floor pump had the wheels setup in no time. For trail riding around New Mexico and Arizona, I’ll tend to run a little higher pressure than some. For the Dissector I’ve found 20-22 PSI in the front to offer enough protection and grip, while for the Rekon 24-26 PSI. Safety third.
Maybe it’s just me, but I often find the subtleties in wheels are more dependent on tire setup than the wheels themselves, unless a particular trait is especially egregious. Given the back-to-back sampling, I was convinced I would detect a difference no problem and in some ways, this was true. The lightness of the wheelset was immediately noticeable, with bursts of acceleration up and over obstacles and when standing up pedaling you could feel the wheels get up to speed with noticeably less effort. But weight usually comes at a cost, both in reliability and general nervousness on the trail when things get rough.
That’s where the BERD wheels really impressed me–on both counts they did not flinch. The ride character was less chattery than expected. A lot of this is thanks to the rims, where the Arch rims strike a nice balance of compliance and toughness for XC/Trail riders. However, having ridden the DT-laced wheels for the previous two years, I still found the overall ride impression was indeed different.
I don’t want to mislead folks and imply these spokes will suddenly make a stiff rim compliant; rather, if a rim already has some compliance, it seems it won’t neutralize that quality. Looking back at the claims made by BERD, I can’t help but think this isn’t just pure marketing jargon. Numerous times I had piloted my Myth hardtail down trails I typically reserve for the Zodiac or other full suspension bikes just to see if I could get the wheels to flinch. Each time I rode away both surprised and impressed–they were quick, comfortable, and in the highest compliment I can give a wheelset, they disappeared beneath me.
Okay, we’ve established they are lightweight, pedal well, and seem to not detract from the riding experience. So far so good. Where the rubber meets the road, however, with any new technology, is how they hold up. If there was one area where BERD spokes really shine, it’s in this department.
My first test of their reliability happened on one of our favorite local rides, Atalaya, where some steep rock maneuvers can add a little spice to your lunch loop. First ride and a grapefruit-sized chunk of rock broke loose and hit the rear wheel on a high-speed descent. The spokes made the strangest sound–imagine a xylophone strummed with granite–and I stopped immediately to investigate the damage. Outside of a scuff on the rim, I was hard-pressed to see where the impact occurred.
With that experiment out of the way, for the next six months I rode the wheels as haphazardly as any other. Jumps were cased, logs misjudged, corners slid, and drops to flat all handled by the wheels without second thought. I ran different tires, with and without inserts, and seemingly couldn’t ruin these wheels.
The final test came during our Aquarius Huts tour where many others would experience punctures and spoke failure. The rope spokes, despite being laced to otherwise softer rims, again never showed signs of concern. Even dogfighting Bryan down some of the most entertaining lines on our tour didn’t even get them out of true. If you have ever had the displeasure of following either of us down a rocky chute, then you know that’s a testament to their strength!
After inspection of the spokes and nipples, I have 100% confidence in their strength for the long haul.
If this is beginning to sound like a glowing review, then you’re right. I’m thoroughly impressed with these spokes and it should give one pause about what we accept as ‘normal.’ BERD went out on a limb and while they weren’t the first to experiment with fiber spokes, they are the first to really make a splash in the market. They’re making lightweight, strong, and reliable spokes that can change the feel of your ride.
This got me thinking about where I would want to utilize these spokes and oddly, counter to the ‘tried and true’ dogma of bicycle touring; I would wager these are the perfect touring wheelset solution. First, they proved to be ultra reliable whether from impact or rough landings. Second, acceleration can really be appreciated on a loaded rig when applied at the wheels. And finally, a replacement spoke can be rolled easily into a tool bag without the awkward storage challenges of a traditional spoke.
Whether you’re building a new set of wheels for your quick and agile singlespeed or your loaded touring rig, take some time and consider the alternative to the steel spoke. You may be as surprised as I am.
- Look great
- Proprietary hubs are now available
- Available in colors
- Expensive at $8 a spoke
- More involved wheel-building process
- Would be difficult to field repair
- Wheel-builders need to research the process
BERD spokes are $8 a piece, with fully laced gravel and MTB wheels starting at $1,399.
See more at BERD.