Tech Breakdown – 2014 Crank Brothers Iodine, Cobalt Alloy Mountain Bike Wheels Roll Out

2014 Crank Brothers alloy mountain bike wheels tech details and specs

Last week, we treated you to an inside look at Crank Brothers, the company. This week, we’ve got the full story behind their 2014 wheels. Or, the alloy ones anyway, the carbon rimmed 11 series will get official next year (but, like most of these, we got a sneak peek at Eurobike).

At first glance, the wheels look the same. But like true beauty, the real story goes much deeper. And in this case, shallower and wider, too.

Before we get into the tech, some background: Crank Brothers’ wheels program started in 2005. Cofounder Frank Hermanson said prototyping the wheels was tougher than their other parts because they couldn’t just whip up rapid prototypes in house. And getting third party manufacturers to create such a radically different design before there was any guarantee it would work was tough. There weren’t many manufacturers that thought their paired spoke rim design would work.

They actually faced the same problem when they first introduced their pedals, which is why to this day their pedals aren’t made by a pedal manufacturer.

With the wheels, they wanted to do it differently in a lot of ways…

crank-brothers-FEA-vertical-buckling-test

All of their rim designs start out with FEA stress analysis for lateral bending, vertical loading (buckling), radial stress and loading and static tire pressure. Once it’s worked out in the computer, they make prototypes and test it for real.

Side note: They said it’s hugely surprising how much of a difference seemingly small changes make. Like changing a curve’s radius by a fraction of a degree can sometimes make or break a rim in certain tests. So the challenge is making tweaks that improve one feature without ruining another.

During lab testing, which is done in their 18-person Taiwan facility, they went through several iterations even after opening tooling. They perform testing on the rims first, then built as complete wheels. Then they hand them off to their sponsored athletes.

2014 UPDATES & IMPROVEMENTS

2014 Crank Brothers alloy mountain bike wheels tech details and specs

Crank Brothers original one-piece wishbone spokeThe split spoke design was created because they couldn’t put the nipples at the rim because the paired design wouldn’t give you much room to put a spoke wrench on it for truing.

The first prototypes used a one-piece “wishbone” spoke that looped through the rim hole (image at left, click to enlarge). They were rideable, but they were very hard to balance and true because as you pulled one side, the curve would slip to one side or the other. Separate spokes pulled through pins were the solution.

2014 Crank Brothers alloy mountain bike wheels tech details and specs

The latest hubs use a simplified axle/end cap system and are much more reliable.

For the hubs, they didn’t want to reinvent it. There were plenty of reliable, proven ratchet and pawl mechanisms, so they went with a vendor they knew. Unfortunately, that vendor’s product didn’t hold up well on the trail -it had about a 17% failure rate- which caused more than a few warranty issues.

With the 2nd generation of the wheels debuting in 2010, they wanted to get a more robust hub and improve their build process. The new hubs proved to be much more durable and reliable -less than 1% failure- and ended up with a better axle endcap system. They also introduced their numerical heirarchy system, offering tiered products at different price and performance levels.

2014 Crank Brothers alloy mountain bike wheels tech details and specs

Now, they’re debuting their 2014 wheels. It gets a streamlined heirarchy with just three lines: Cobalt (XC), Iodine (AM) and Opium (DH). Sage is gone. Within the lines, you have up to four tiers: 11 is the best, designed with everything they want in a premium wheel and cost as an afterthought. The 3 level is high performance for those where cost isn’t an after thought. 2 is a solid upgrade choice for enthusiasts, and 1 is really aimed at the OEM spec level for bike brands that want to use a branded product to enhance showroom value.

2014 Crank Brothers Rim Widths

2014 rims are all 2mm wider on the inside. Internal widths listed.

With the hubs and spokes dialed from the 2nd gen, the rims saw the bulk of the advancements for 2014. When they first started, tubeless was really coming into its own, so they wanted to make a rim that was tubeless ready right of the box, not needing tape to cover spoke holes. That part of the design hasn’t changed -the rims still have a solid rim bed- but the depth, bead seat and width have. Those changes helped them achieve all three redesign priorities:

  • Improve the strength to weight ratio while keeping their design aesthetics
  • Optimize durability and stiffness
  • Improve vertical compliance
2014-Crank-Brothers-alloy-rim-comparison01

Prior generation rims on the left, 2014 extrusion on the right.

For alloy rims, the tire bead wall heights are lower, rim are wider and the extrusion has overall taller rim height. The rims are all 2mm wider, and total rim depths grew while interior bead hook walls all got shorter. Depths vary depending on the rim’s intended application:

crank-brothers-2014-rim-profile-comparison

The result is rims that are laterally stiffer while being lighter, improving the overall wheels’ stiffness to weight ratio anywhere from 9% to 14% (Cobalt 29er rear used for the example).

They also wanted to improve tubeless tire compatibility. With tire technology improving, they could improve the interface. The rim bed’s center groove has a smooth curve leading to sloping, ramped faces, all of which helps the tire slide into place easier during initial setup and helping it settle back into place quickly if you do burp air on the trail.

The 1.7mm reduction in bead hook height helps hold the tire in place. The 0.2mm hook thickness reduction and revised profile, along with the wider stance, all help make for a bigger, rounder tire footprint. Like the depths, the bead hook shape varies from Cobalt to Opium, catering to the type of riding and tires likely to be used.

Their original rims had a brushed finish. It looked good, but the 3rd gen rims get a new cold worked, shot peened finish that hardens the surface and reduces the likelihood of cracks. Overall strength is improved by 15%. Logos and graphics are laser etched on top.

hans-rey-testing-crank-brothers-wheels

The legendary Hans Rey joined us for our test ride.

Part of their real world testing is done by Hans Rey and Richie Schley, both of whom head out for multiday rides in remote areas. Obviously, the paired spokes aren’t standard items most shops are going to stock, so their vote of confidence by using them when they’re out of range of easy repairs speaks to the wheels’ durability.

EASE OF SERVICE

2014 Crank Brothers alloy mountain bike wheels tech details and specs

The other side of the durability story is their ease of repair, something their engineers say isn’t commonly known. In fact, they say some shops send back wheels to be trued simply because the design intimidates them or they looked complicated. In fact, that couldn’t be further from reality.

Tim Young, product developer and former service and warranty manager, demonstrated how to build a wheel in under 20 minutes and without any special tools. In fact, the only things needed are a standard spoke wrench, truing stand and spoke tension caliper. The wood base can be made by any shop that actually thinks they may build a Crank Brothers wheel from scratch – it’s a high tech chunk of 2x4s and duct tape with a cheap skewer drilled through the center.

2014 Crank Brothers alloy mountain bike wheels tech details and specs

Simply insert the lower part of the spoke through the hub holes. The spokes don’t weave between each other and the holes are spaced and oriented so that you can’t mess it up. And the upper part of the spokes will only reach far enough to connect to the correct bottom portion, so there’s literally no way to do it wrong. To install the upper spoke, simply slide the pin into the rim hole and insert the spokes about half way while angled flat with the rim bed. Once both are halfway in, pull and twist them toward the hub.

2014 Crank Brothers alloy mountain bike wheels tech details and specs

The spoke heads have two flattened edges that rest against the side of the rim flange so they won’t spin during truing. From there, simply hand tighten the threads evenly before putting in a truing stand for tensioning and balancing. It really couldn’t be easier. Oh, well, actually it could: Need to order parts? Front and rear, drive and non-drive side spokes are all exactly the same per model. Get a couple extra and throw in your pack and you’ll have what you need no matter where the damage occurs. And you can repair the wheels trail side without even having to remove them from your bike.

Most standard bicycle wheels are touched by human hands during assembly, but some are mostly built by machine and only see a quick inspection in a truing stand. Others get intermediate hands on attention. Crank Brothers wheels are all 100% handbuilt at all price points.

SPECS & MODELS

2014 Crank Brothers Cobalt 3 alloy mountain bike wheels

Quick notes: Cobalt 11/3 and Iodine 3 only come in 27.5 and 29er, lower level models will have 26″ options. Cobalt 3 gets an alloy freehub body and secondary machining on the rim’s spine. The Cobalt 2 has a steel freehub body and no machining, and it comes in 26″.

All endcaps are included in the box, and XD driver bodies are available aftermarket. For them and dealers/distributors, they went from 50 wheel SKUs to 13 by making all models use swappable end caps rather than dedicated axle systems.

2014-Crank-Brothers-Cobalt-Wheel-Specs

2014 Crank Brothers Iodine 3 alloy mountain bike wheels

2014-Crank-Brothers-Iodine-Wheel-Specs

2014 Crank Brothers Opium DH alloy mountain bike wheels

2014-Crank-Brothers-Opium-Wheel-Specs

Wheel size options? How ’bout this handy chart:

2014-Crank-Brothers-Wheel-Size-Options-Chart

What about the carbon wheels? They’re coming, but they won’t be shipping until spring 2014, so they’ll announce all the tech info on those closer to release. The basic idea behind the alloy rim updates were applied to carbon, too, but the stiffness improvements on those were considerably higher. Should you wait? Only if you wanna spend more than twice as much or you’re super hard on your XC equipment. Our initial rides on the new wheels were impressive, doing their best to hold a line on some severely rutted out trails and loose, obstacle-laden descents. They’re on their way back to our office with an assortment of other fresh Crank Brothers parts for a proper long term test on local trails.

CrankBrothers.com

Comments

Ck - 11/19/13 - 2:10pm

Good tech info, lots of stuff I never knew about their wheels. It’s enough good info that I wouldn’t ignore them as a wheel option in the future anymore. It’s not going to make a dent in the opinion of the BR commenter crowd but it’s a start in the right direction.

ccolagio - 11/19/13 - 2:57pm

i love the hi tech ping pong table/wheel assembly area

yee_haa - 11/19/13 - 3:28pm

What about XD free hub bodies? Are they done testing? When/will they be available? At BR’s most recent report: http://www.bikerumor.com/2012/12/27/manufacturer-round-up-whos-making-xx1-freehub-bodies/ seems like CrnkBros were working on it…

mike - 11/19/13 - 3:33pm

Shops send wheel’s back for truing? Time to find a new shop!!! Is the industry really that short on Personal with the technical expertise?

Skeeter - 11/19/13 - 3:40pm

I still think they’re beautiful wheels, and I’m glad I didn’t jump at the chance to be an early adopter with that failure rate. I’m very happy to hear that they’re addressing their quality issues. I’m now considering a set after being cautious about them based on quality concerns. I appreciate their products even more after this write-up and your factory tour post. Thanks!

Tyler, did you get an editor? I found no grammatical errors in your post, which seems very strange for a longer piece like this one. I had to look up Stock Keeping Unit (SKU), but that’s feasible. Nice post!

Philipp - 11/19/13 - 4:32pm

Okay, the eq. stresses are well above yield strength. Fair enough.

DG - 11/19/13 - 4:50pm

“The new hubs proved to be much more durable and reliable -less than 1% failure-”

How much less? A 1% failure rate is not low.

Mindless - 11/19/13 - 4:50pm

Lower bead hooks are stupid. Get proper UST.

Mattbyke - 11/19/13 - 5:16pm

Strangely enough , I’ve been hammering a set of 2010 iodines.
No trouble other than a sticky free wheel preventing back pedaling. Too thick a bearing lube rendered it useless. They also are effected by the tightness of the skewer. To tight and no backpedaling. The aluminum for the rim is soft and bends easy.
Once I worked out the bugs zero issues. Never touched the spokes .

Josh - 11/19/13 - 6:12pm

@Mindless – I would argue that “proper UST” is stupid. More importantly, have you ever posted a positive comment on Bikerumour? Or anywhere for that matter?

Max - 11/19/13 - 6:28pm

@Philipp: But the picture is so colourfull!

gravity - 11/19/13 - 6:48pm

Oh awesome – another Crank Brothers thread!

CDG - 11/19/13 - 8:43pm

@Josh…agree. Not a CB fan, but these are nice looking wheels. Can’t speak of the performance, as I have never tried them out.

dwiz - 11/19/13 - 9:58pm

Their wheels are no good. Never have been and never will be. I see lots of bikes come and go through the shop. LOTS. I’ve never seen a bike with them. I’ve never had a customer ask about or do a special order for them. Ask a service guy about them and you’ll get a “deer in headlights” response. This isn’t an attempt to stir sh-t. But rather ask how and why they are nonexistent? Serious and intelligent responses need only to respond. You Turkeys

Tim - 11/19/13 - 10:07pm

I have limited experience with CB, but in the past have been dissuaded from buying anything beyond their pedals because of their reputation. It looks they’re making a concerted effort to fix the problem at the source, and spend enough money on hiring respected testers with name recognition and on write-ups like this one (if it’s indeed paid for). I hope it works out for them- they do seem serious about improving their brand.

Dr.Unk - 11/19/13 - 10:25pm

@Mike

“Is the industry really that short on Personal with the technical expertise?”

Most smart bike mechanics go off to college to get a “real job”; when $18/hr is considered amazing pay for a mechanic, why would anyone stick around long enough to learn the trade?

Neil - 11/20/13 - 6:32am

Boo-hoo, Crank Bros. “there weren’t many manufacturers that thought their paired spoke rim design would work” waaaaay back in 2005, when a little-known company from Japan had already been making them for years.

http://www.retrobike.co.uk/forum/viewtopic.php?t=162170

Even the worst wheelset companies have moved on from this failed design. CB doubles down and expects internet love.

Brad - 11/20/13 - 9:59am

@dwiz

You can see into the future!? Amazing stuff right there. I had a set of Iodines that I rode the piss out of. The rims dented to easily and the hubs had some engagement issues… but zero problems with the spoke layout. In fact, despite some gnarly dents that got pulled out with a wrench, I hardly ever had to true the wheels. I’m stoked that they kept the design and think, just like anything else, it will improve with time. If their newer wheels are truly better, I’ll be considering them again… but I will admit that I’m curious to read some long term reviews first!

thesteve4761 - 11/20/13 - 10:07am

@ DR. Unk:

Hit the nail directly on the no insurance having head!

Tim - 11/20/13 - 1:44pm

Geez. Paired spokes. Somehow I totally missed it in the pics. Terrible idea. There are large, unsupported gaps, and there are short, highly supported areas on the rim. Ick. Same feeling I have for Rolf wheels and any other paired spoke designs. There’s a reason traditional J-bend spokes in an unpaired pattern remain the same after so many other improvements to the design of the bike.
I guess they are “good enough”, though, or Rolf would have gone out of business. “Good enough” is not the benchmark I aim for, though.

lonefrontranger - 11/20/13 - 2:31pm

I had a set of the original Cobalts on my Anthem 26er from early May 2009 until the day I sold the whole rig late last October to get my Niner. The wheels saw 3 1/2 years and 4 pretty hard MTB XC racing seasons in the Rockies. Never had a single issue with them and they were so much stiffer and lighter than the stock OEM pair the bike came with. I’ve broken 3 sets of eggbeaters and ultimately switched to ATACs tho, so I’m familiar with CB warranty issues.

EvanT - 11/20/13 - 4:03pm

@Mike;

I think the real issue is the increasing amount of nontraditional wheels which have flooded the marketplace. Whenever dealing with Roval wheels that required spoke replacement it makes financial sense (cents, ba-dum-tisssh… and the crowd goes wild, I’ll be here all week folks!) to ship it back to Specialized as to replace a single spoke required the de-tensioning of the entire wheel. What could have been a 10-15minute job depending if it was a front or a rear wheel is now a 1hr+ job.

Campy / Fulcrum wheels have different albeit similar problems where a replacement nipple needs to be dragged into place on certain models of their rims. While I haven’t broken a nip on my Fulcrum’s yet… I dread the day.

Mavic wheels are chock full of proprietary parts and require proprietary tools… pounding several PBR’s helps the issue immensely. It doesn’t make it easier, just more entertaining.

Certain Bontrager wheels have a goofy, non load bearing (and easy to damage) fairing that gets in the way.

Easton wheels require the tire to be removed to true from inside the rim… not a problem with clinnchers, I suppose other than adding the cost of a flat fix to the cost of the wheel truing or spoke replacement, but for tubulars… A 10-15min project just turned into a titanic pain in the ass. Older Roval wheels had this problem, but Specialized adjusted for 2013 and beyond.

So my point being… you can make more money as a shop by saying screw it, boxing it, shipping it, and making it someone else’s problem.

Padrote - 11/20/13 - 4:56pm

I never had a single issue with my ford pinto exploding. hope this helps everyone.

Brendan - 11/21/13 - 7:26am

Seems kind of heavy and expensive. I probably won’t be finding out if they are reliable.

bin judgin - 11/21/13 - 4:16pm

what mechanic is getting paid 18 an hour? ill kill them and wear their skin.

dervelo - 11/23/13 - 10:50pm

Anybody have any reliable mountain bikes wheels they would recommend around 300-400 ? Seems like a minefield of marketing over engineering out there

nobby nic - 11/24/13 - 10:00am

Funny to see how sheltered the Kronolog dropper post is on the Crank Brothers Niner bike in the first picture. I had a Kronolog once (2 counting warranty/upgrade), and it lasted a grand total of one riding week due to slipping down/occasional binding on return. All because of what a rear wheel (dirt, naturally) throws at it.
Oh, and their “premium” cleats are softer than butter.
No insight regarding CB wheels except they have some reliable and sexy competition at each of their price points.
Other than their mechanical faults, they seem fine.

Mindless - 11/25/13 - 12:45am

@Josh: proper UST profile, like say TCS rims from WTB work. That is a positive comment. Everything else is stupid.

nobby nic - 11/25/13 - 6:04am

@dervelo:
I found a set of Roval Traverse 29″ for my Sb95 on Ebay for $200 new. Light, wide, strong, and I can not seem to kill them.

PAD - 07/01/14 - 6:50am

Have tried a cobalt 11 carbon wheelset. The problem is when you’re going to put some air pressure to about 40-50 psi. The edge of the rim wall will deflect and you will notice some wave portion when rotating the wheel. Truing is not possible as the deflection is only at one side of the wall. Distributor recommendation is around 35 psi. Cobalt 3 is quite OK when you want to have a 40-50 psi.

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