How does Santa Cruz build wheels? Wil goes to the factory to build his own set of Reserve Carbon wheels

by Wil Barrett 4

According to Syd Newsom, Head Of Wheels at Santa Cruz Bicycles, “wheelbuilding is not magic. It’s a skill set that can be taught, and the goal of our training is to create a very consistent end product.” Within 10 minutes of wandering around the assembly floor of the Santa Cruz factory in California, it becomes apparent that Santa Cruz takes wheelbuilding very seriously.

During the recent launch for the brand new Blur and Highball, I enjoyed an entertaining guided tour through the Santa Cruz factory by the company’s CEO, Joe Graney. For anyone who’s visited the Santa Cruz’ Mission Street factory before (visitor tours are run every weekday), you’ll know that Santa Cruz does all of its bike assembly in-house, rather than out of Taiwan or China like most other brands. The big warehouse is like a novelty supermarket filled with ceiling-high racks chock full of swingarms, linkage kits, bearings, forks, brakes, cassettes, cranksets, handlebars, grips, headsets – and all of the other goods needed to create a complete bike. The main workstations are a hive of activity each and every day, where bikes are built up, wrapped up, then boxed up in preparation for being shipped out to a Santa Cruz dealer somewhere around the world.

santa cruz carbon factory
The factory floor in Santa Cruz, California. Photo: Gary Perkin.
santa cruz carbon factory box shelf warehouse
Like a supermarket, except this one you actually don’t mind being in. Photo: Gary Perkin.
santa cruz carbon factory frame mechanic workshop
Blur frame packing. Photo: Gary Perkin.

A Wheel Commitment

In addition to bike assembly, Santa Cruz also builds its own wheels in-house, which fewer people are aware of. Boxes filled with rims, spokes, nipples and hubs arrive at the factory loading dock via huge semi-trailers, and then the components are racked up and prepped to be turned into complete wheels that’ll either be sold with a bike, or on their own aftermarket.

There is clearly a huge investment in resources in order to build wheels here – the physical floor space, staff, time and expensive machinery that Santa Cruz has dedicated to it is impressive. Compared to parts storage and bike assembly, the wheel area is almost as big. Not only are the machines expensive, but each staff member must go through 6-8 months of training before they’re qualified as a Santa Cruz wheelbuilder. Regardless of their prior mechanical experience, they’re first taught to build wheels by hand before getting anywhere near the machines.

santa cruz carbon factory wheel build mechanic tools
One of Santa Cruz’s expert wheelbuilders, Victor. Photo: Gary Perkin.

“Wheelbuilding is not magic. It’s a skill set that can be taught, and the goal of our training is to create a very consistent end product.” Syd Newsom, Head Of Wheel Department.

spoke nipples
These are oil-soaked nipples. And Google’s going to have a difficult time SEO’ing this caption. Photo: Gary Perkin.

During my tour of the factory, some stupid person decided it would be a good idea for me to build my own wheels. Thankfully I had the assistance of Santa Cruz’ top wheelbuilder, Keila Bauerlein, who guided me through the whole process. It was just like the scene from Ghost. I was Demi Moore, and Keila was my Patrick Swayze. Except it was a lot noisier. And more stressful. And people were watching, which it made it a bit awkward.

Hand Building With Robotic Help

The first step of the process involves the hubs being loaded by hand with sets of spokes arranged in four groups. For 28h wheel builds, there are four sets of seven spokes. And for 32h wheel builds, there are four sets of eight spokes. The loaded hubs are oriented so the hub decal will face the rim decal (a small detail that experienced wheelbuilders will appreciate).

From there, a loaded hub is connected to its rim. This happens on a BMD semi-automated lacing machine. Santa Cruz owns three of these machines, which are valued at around $30k USD a piece. They’re named Lance, Lacey and Eva.

The machine is programmed with the all the dimensions of the rim and hub, so it knows how many spokes it’s dealing with, and what base tension it needs to start with. The wheelbuilder sits at the station with the rim laid out just above their lap like a slide guitar. Each spoke is guided into place before the machine sucks up a spare nipple, then and pushes and twists it through the hole in the rim, where it threads over the spoke end. There’s a satisfying blast of compressed air, then it’s on to the next spoke.

santa cruz factory wheel build wil
Wil under the watchful eye of Keila. Photo: Gary Perkin.
santa cruz factory wheel build wil
The semi-automated spoke lacing machine costs about $30k. No wonder Keila’s watching so closely. Photo: Gary Perkin.
santa cruz factory wheel build wil
An expert wheelbuilder can lace a wheel in around 80 seconds. Wil? Just a bit longer than that. Photo: Gary Perkin.

Once a wheel is laced up, it’s time for fine-tuning the tension. The wheel is placed onto a track that feeds it into the BMD truing machine. There are also three of these machines, and they’re a little more expensive – $60k a piece. They’re named Rosie, Big Bertha, and Wall-e, and they’re absolutely marvelous machines to watch in action.

Big rubber blocks compress onto the spokes to relieve them, then spoke keys attached to complex articulated arms begin to work their magic on each spoke nipple. The wheel is spun forwards and backwards, while lasers monitor vertical hop and lateral deflection to work out which nipples need more or less tension. And because tightening one spoke affects the tension on all others, seeing the machine rotate the wheel back and fourth as it contemplates its next move is wholly addictive.

Once off the truing machine, every single wheel is then hand-finished and checked for correct spoke tension. Spoke tensiometers are used to evaluate final spoke tensions, with a Mach-1 QA machine providing numerical readouts of dish, lateral movement and overall roundness. The final process involves a visual check for any blemishes, then tubeless tape and valves are installed before the wheels are racked up or boxed up depending on their final destination.

santa cruz factory wheel build wil
Every single wheel is finished and checked by hand. Photo: Gary Perkin.

Reserved Carbon

Santa Cruz builds a load of different wheels in house, but it’s been the new Reserve Carbon rims that have been going absolutely gangbusters for them lately. Introduced last year, the Reserve series are the first carbon fibre rims to be developed by Santa Cruz, and for the large part, they’ve almost entirely replaced demand for ENVE rims on complete Santa Cruz bikes.

Available in both 27.5in and 29in diameters, the Reserve rims come in 27mm and 30mm internal widths, and there’s also a skinnier (and lighter) Reserve 25 available in 29in only. The rims use thick hookless sidewalls that measure 2.8-3.7mm thick depending on the model.

Each rim gets offset spoke drillings, which helps to provide even spoke tensions from drive to non-drive side. The spoke beds are reinforced with extra thick carbon fibre, but only in a small square patch around each spoke hole. This way the strength is applied where it needs to be, without adding extra weight to the rest of the rim.

santa cruz carbon fibre reserve rim wheel
Carbon fibre rims ready for a’buildin. Photo: Gary Perkin.

This distinctive design was established through in-house testing and development at Santa Cruz’ carbon lab. Numerous square sheets of carbon fibre were made up with different layups, thicknesses and reinforcements in order to test the pulling force that could be applied via a spoke under tension. Eventually the team got to the point where they weren’t breaking carbon sheets anymore – just spokes and nipples.

Production rims are manufactured in Asia, using a metal external mould, and a unique hard wax-type mould for the hollow inside. The goal is to create a smooth surface both inside and outside, with higher compaction rates for a more dense and void-free structure. What’s particularly cool about the internal wax mould is that it’s reusable. Though it initially remains solid up to a certain temperature and pressure, during the final curing process it actually liquifies, allowing it to be evacuated out of the rim. From there it can be cooled and re-moulded into a solid state for use for the next rim. Neat eh?

santa cruz reserve carbon rim
A cross-section of a Reserve carbon rim. Note the thicker material around the spoke beds.

Danny MacAskill Tough

One thing Santa Cruz is particularly sure of with its Reserve rims is their strength. During the development period, plenty of testing of both its own designs and other brand’s rims were put through the wringer in the lab:

We created a test in our lab that simulates one side of the rim landing directly on a square-edged rock from over 3 feet in the air with no suspension, and a lightweight tyre inflated to 25psi. As we began to put some of the other rims on the market through this test, we broke a lot of them more or less like we expected to – on the bead – but we also found that a critical failure mode was the spoke nipples pulling through the rim due to the sudden increase in spoke tension as the wheel flexed on impact.”

santa cruz carbon fibre reserve rim wheel
Demand for Santa Cruz’ Reserve carbon wheels has far outstripped company expectations. Photo: Gary Perkin.

In addition to lab testing, Danny MacAskill proved to be an integral part of in-field testing. Danny was using prototype Reserve rims as far back as a year before their official release to public, including for his hit video ‘A Wee Day Out’. According to Santa Cruz, he’s still on the same set of wheels. Well, aside from that set.

Because of this confidence in its product, Santa Cruz is selling the Reserve wheels with a lifetime warranty. From what we’ve been told, the warranty isn’t just to cover manufacturing defects – Santa Cruz will replace your rim free of charge if you’re able to break it while riding. Even if you’re an absolute rim-dinging idiot like Danny. Backing over your wheel with your car is a different story, but even then Santa Cruz says it’ll do what it can to help out customers.

santa cruz reserve carbon wheels
It’s honestly amazing they’re still round after what Wil did to them.

The wheels that I built during my factory tour utilised the middle-width Reserve 27 hoops in a 29in diameter. The rims are laced to DT Swiss 350 hubs with slender Competition Race spokes and Sapim mechanically-locking nipples. For an extra £300, you can get the same wheels built with Industry Nine Torch hubs instead if you want a bit more buzz.

Santa Cruz Reserve 27 Carbon Wheel Specifications

  • Carbon fibre Reserve 27 rims
  • Designed for trail riding
  • 29in diameter
  • Rim depth: 25mm
  • Internal width: 27mm
  • External width: 34mm
  • DT Swiss 350 hubs, 110x15mm front & 148x12mm rear
  • 28x DT Swiss Competition Race (2.0-1.6mm) J-bend spokes
  • 3-cross spoke lacing
  • Sapim 18mm Square Drive Secure Lock nipples
  • Actual weight: 1750g
  • RRP: £1599
santa cruz reserve carbon wheels
The offset spoke bed ensures even spoke tension for a more balanced wheelbuild.
santa cruz reserve carbon wheels
Thumb for scale.
santa cruz reserve carbon wheels dt swiss 350 hub
DT Swiss 350 hubs as standard, though Industry Nine Torch hubs are available as a £300 upgrade.
santa cruz reserve carbon wheels rims wil box
Signed off by some wheelbuilding experts. And Wil.

Though I’ve ridden several Reserve wheelsets on complete Santa Cruz bikes, this is the first wheelset I’ve been able to test and review in isolation. I’ll be riding the Reserve 27 wheels over the coming months, so keep your eyes peeled for the full longterm review.

In the meantime, you can check out more details on the Reserve wheels via our launch story, or head to the Santa Cruz website for more information.

Comments (4)

  1. Do they use thread lock on the nipples?

  2. @footflaps – They do, but it isn’t a Loctite-type glue. Instead, the Sapim Secure Lock nipples feature a patented mechanical thread locking system, which apparently negates the need for traditional threadlock.

    Can definitely see the appeal there from a mass-wheelbuilding perspective!

    More info here; http://www.sapim.be/nipples/brass/secure-lock

  3. Very interesting. Nice article by the way 🙂

  4. @footflaps – Thank you for the kind words! Was a lot of fun to put together – Definitely less stressful than the wheelbuilding itself 🙂

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