Manufacturer Round Up: Who’s Making SRAM XX1 Drivers & What Are the Design Challenges?
A lot of folks are taking a hard look at the new SRAM XX1 group, and not just because it’ll drop a half a pound from a traditional 2×10 group. Early reports, including our own testing by Tyler and myself, suggest the performance and gear range really hit the sweet spot for everything from XC to all-mountain riding.
So, as you’re planning the big upgrade, wheels will be the other half of the decision. We asked around the major wheel and hub brands to see who’s working on what, and here are the replies from American Classic, Chris King, Crank Brothers, E13, Easton, Hope, Industry Nine, Mavic, White Industries and Profile, among others.
UPDATED: Specialized wheel info added (2p EST). Syntace info added (2p EST). Corrected Easton’s answers to design differences (5:30p EST). Stan’s No Tubes, Hadley Racing, Rolf Prima and SUNRingle added (1/2/12 @4a EST). Reynolds Cycling added (1/3/12 @2p EST). Ritchey responses by Tom Ritchey! added (1/4/12 @ 3p EST.) DT Swiss info added (11P EST @ 1/9/2013.)
BIKERUMOR: Will you be producing an XX1 compatible freehub body?
American Classic: Yes, the cassette bodies are in final production.
Chris King: They’re looking into it.
Crank Brothers: Yes, crankbrothers is currently testing the XX1 group and cassette on our wheelsets.
DT Swiss: Yes, as one of the companies involved in helping pioneer this standard, we’ve been producing the XD Driver body for several months now. The XD Driver (as it appears today) was a collaboration between DT’s and SRAM’s engineers.
E13: Yes, we will. We are currently finishing prototyping models right now. I was actually going through fit checks on the freehub body and the new cassette on Tuesday [12/18/2012].
Hope: Yes. It’s already available.
Profile: We will be offering an XX1 compatible freehub body for our Elite MTB cassette hubs at some point in 2013. We haven’t had a lot of demand for them so far, so there’s not a huge rush to get them built tomorrow, but second quarter is possible. Don’t hold a gun to my head on that date- sometimes stuff happens faster, sometimes it takes longer if we get bogged down.
Stan’s No Tubes: Yes
Syntace: Yes – it’s in the works now.
Ritchey: Yes, Ritchey will offer XX1 freehub bodies.
White Industries: Yes, we will be offering the new XX1 and estimate the freehub body to be ready the beginning of February, with the launch date set for NAHBS.
BIKERUMOR: For what specific hub or wheelset (if applicable)?
American Classic: They will fit any of our wheelsets and hubs, but it is for mtb, so I guess the correct answer is they will fit our mtb wheelsets and mtb hubs.
Crank Brothers: The freehub will be compatible with current crankbrothers 3 and 11 level wheels. In the future we will offer this option on all 3 and 11 level wheelsets. Due to the higher price point of the XX1 group, we will not offer this on our more affordable 2 level wheels. We feel that this is applicable for both all mountain and cross country riding, so we will offer this on both the iodine and cobalt platform.
DT Swiss: Our XD driver is compatible on any DT Swiss Star Ratchet drive hub or wheel set. Currently the XD Driver is only available as a separate purchase. Moving forward, DT Swiss will have XX1 compatible wheels and hubs in our line-up. There are just a few exceptions that your readers need to be aware of though. Due to different internals, our DT 340 hubs or any of our pawl-based wheels/hubs are not convertible to the XD Driver. OEM wheels built from DT components, may or may not be convertible – it’s best to check with your local bike shop prior to purchasing parts.
Easton: The XD Driver will work with all Easton M1 hubs (Haven, Haven Carbon, EA90XC, EC90XC, EC70 Trail, etc…)
Hadley: We will be producing an XD freehub body made from 6AL-4V titanium.It will be compatible with all Hadley rear hubs 135mm and 150mm dating back to a manufacturing date of 2002
Hope: It fits straight onto our pro 2 EVO hubs and wheels. The older pro 2 hubs just need an additional axle change.
I9: We have XX1 freehub bodies available for all of our current mountain wheelsets and “Classic” hubs. They will also fit all of our mountain hubs and wheels going back to the companies’ first wheels produced in 2005.
Check out Tyler’s first look and install of the I9 XX1 driver here.
Mavic: It’s an ITS-4 freehub body, so it will fit Crossmax SLR, ST, and SX, plus the 2013 CrossTrail.
Profile: Our Profile Elite MTB hubs.
Stan’s No Tubes: They will fit our older ZTR hubs or our current 3.30, 3.30 Ti, & 3.30HD hubs. Essentially the consumer should be able to retro fit any of our mountain bike wheels. We also build with DT Swiss 240 hubs and Hope Pro II EVO hubs. We have a few of the DT Swiss 240 XX1 freehub bodies in stock already and willing be receiving the Hope XX1 freehub bodies shortly.
Syntace: Will be available for the whole Syntace MX Wheel series.
Ritchey: Our XX1 freehub will be a quick and easy swap for all current and future model Ritchey Vantage II mountain wheels, which are available in 26”, 650b and 29er versions.
White Industries: The freehub body will be available on a number of hubs, however, the main two that are targeted are our MI6 disc rear and the MI5 rear for rim brakes.
BIKERUMOR: When do you expect the product to be available at local bike shops?
American Classic: Feb 2013
Crank Brothers: April 2013.
DT Swiss: Now, today, as we speak….(err, type!) Our version of the XD Driver is available for Bike Shops to order through any of our distributors. We have versions for quick release, 12x142mm , and our slick 10x135mm RWS system which helps bring thru-axle stiffness to open drop-post (135mm) frames. More details can be found here.
E13: We will be in production with them in February, so if shops get them on order, they could arrive on the sales floors before March kicks in.
Easton: January 2013.
Hadley: Mid Feb 2013.
Hope: We’ve been supplying to retailers for the past month (December 2012.)
I9: We have been shipping our XX1 freehubs since early October and currently have them in stock.
Mavic: The kit should be available in shops by mid Feb 2013.
Profile: Sometime second quarter 2013.
Stan’s No Tubes: Feb 2013
Syntace: Late spring 2013
Ritchey: Initial testing from our team riders has been very positive, so we’re hoping to have freehub bodies in shops by late March 2013.
White Industries: February
BIKERUMOR: How much will it cost?
American Classic: $85.00 msrp . Or it can be ordered pre-installed on a brand new wheelset or hub at no extra charge.
Crank Brothers: $100 MSRP
DT Swiss: MSRP is in the $100-120 range. The kit includes a XD Driver body and a proprietary end cap (required by the reduced freehub body diameter on the 10T cog side). If the rider desires to switch their axle type as part of the upgrade process, a non-drive side end cap and possibly an internal axle (for older generation hubs) will also need to be purchased. Again, best to check with yout local bike shop to determine what will exactly be needed.
E13: The suggested MSRP in the U.S. for the freehub kit will be $97.95 and it will include the freehub body, new premium bearings, springs, and pawls.
Easton: $100 MSRP
Hadley: End user price will be $165.00 – $180.00 U.S. and include the freehub with new bearings, pawls, seals and a new axle assy in any configuration ( QR, 12mm X 142mm, ect ).
Hope: The new free hub body is £65 in the UK.
I9: MSRP on a freehub shell-only is $90, a freehub shell with inner bearings and spacer is $110, and a complete freehub with all new pawls and springs is $220. The most common upgrade kit is the shell with inner bearings, as the rest of the parts will transfer over from a rider’s existing hub.
Mavic: MSRP is not yet determined.
Profile: We will probably offer them first as an option with new hub sales, more likely than not without a price increase over the standard 9/10 speed Shimano/Sram compatible body. It will depend on the material we use, as well, obviously if we manufacture it out of Ti, it will be more expensive than if we make it from CrMo or Aluminum.
Stan’s No Tubes: $80 MRSP for the 3.30 hubs $112 MSRP for DT Swiss 240
Syntace: MSRP – $79
Ritchey: We’ll be competitive with other offerings in the market.
White Industries: The MSRP kit will be $120.00
BIKERUMOR: What do you think are some of the advantages or disadvantages to the new XX1 freehub body?
American Classic: Advantages: it fits 11 speed in a 10 speed spacing. Does not require wheel re-dishing. Provides a large gear range for the rider.
Crank Brothers: The biggest disadvantage we can see is the range is a little narrower than the 2×10 or 3×9 system. However, the simplicity of the system is very nice for all mountain riding. Weight loss and lack of chain suck/chain drop all seem to outweigh the range issue when riding the local trails we have here in Laguna Beach.
DT Swiss: The advantages are numerous. Many of us here within the DT offices have been running since single-chain ring set-ups for quite some time. All of like the simplicity and the advantages a single-front chain ring system can provide. One of the big advantages to the XX1 system specifically is a wider range cassette featuring deeper climbing gears over the systems we currently run. The bigger cassette should provide great for long days in the saddle. Specifically focusing on the freehub body, we’re fans of how the freehub interface has been engineered to address the design specific to the XX1 cassette. It’s also pretty neat that the cassette uses the established locking interface to mount it – no new tools required. The only real disadvantage we can see is educating the cycling public on how this interface and design differs (and why it needed to) over previous designs. It’s a hole new deal for some and it will take some time for people to become familiar with it’s nuances.
E13: We are really fans of bigger bearings in rear wheels and freehub bodies. We would love to have seen bigger bearings in a new freehub design. A little more weight from a larger bearing and hub shell barely increase the angular momentum (acceleration) of the wheel. So if your rims are light and durable, your wheel can actually accelerate as well or better than a lighter wheelset with lightweight hubs and heavier poorly designed rims.
When we overlaid the new model with our current freehub, our bearing actually poked through the outer edge of the freehub. So we had to change a few things to accommodate the new shape. On the positive side, the new shape will keep cassettes from biting into alloy freehubs as badly.
Easton: Advantages : Our design keeps the same bearing size (28mm OD) as our regular SRAM 9/10 speed mountain cassette body. This isn’t really an advantage over our old cassette bodies, but compared to most competitor designs our bearings should be more robust.Due to the splined cassette/freehub interface only engaging on the large 42t cog, galling of the freehub body by the cassette should be all but eliminated. The design seems to offer a really strong interface between the cassette and freehub, the cassette is super easy to install and you get the benefits of 11 speeds over a huge range. Disadvantages: Don’t really know, it doesn’t have 12 speeds?
Hadley: The XD freehub body uses a precision diameter to locate the cassette which eliminates the sloppy mounting of the old style interface and it is also lighter because most of the spline is removed. The way the cassette drive spline interfaces with the freehub also eliminates gouging. So you get 3 obvious advantages. I don’t see any disadvantages.
Hope: It’s really the ability to use a small chain ring and still have a wide range of gears. It’s the same as our own 9t cassettes we are working on, giving you a true 1X setup.
I9: One of the big advantages is that you don’t have to worry about individual steel cogs causing gouges in the XX1 cassette body, as they can in an aluminum cassette body. This is due to the wide contact area between the freehub body splines and the inner cog on the XX1 cassette that transfers torque to the freehub. You also have almost no risk of the threads on the freehub being damaged during cassette installation, since the inner tube on the cassette doesn’t allow misalignment during installation, and their is more material supporting the threads. Traditional aluminum cassette bodies can have the threads damaged during installation due to cross threading or over-torquing the lock-ring, since the material thickness at the end of the freehub is very thin. There is also a small weight saving of about 13 grams on our XX1 freehubs vs. our traditional freehub. I don’t perceive any real disadvantages with the freehub, and feedback from the field so far has been overwhelmingly positive.
Mavic: XX1 clearly presents benefits in terms of weight and simplicity for the all-mountain or enduro rider. In terms of the wheels themselves, there’s really no difference and, and the freehub body change is a really simple procedure.
Profile: I think it’s a tremendous advantage for SRAM, because only SRAM cassettes will work with it. There’s an advantage for consumers, who get an even wider range of gears on the same cassette. It’s sort of a pain for aftermarket manufacturers, who have to build a different cassette body for yet another standard being changed.
Stan’s No Tubes: This cassette being a single piece will eliminate the gauging of aluminum freehub bodies. SRAM designed it to work with existing standards so it would be easy for companies like us to develop a XX1 freehub body.
Syntace: Comparable to other freehub bodies.
Ritchey: For a company like Ritchey, which has been involved with World Cup level racing since the very beginning, the X11 freehub body makes it possible to simplify the drivetrain and provide a more reliable system for racing. This is something I’ve been a believer in for decades—in the 1990’s I introduced a wide-range Ritchey 2×9 drivetrain as a means to eliminate chain suck and dropped chains, the sort of things which can cost you podium spots in a race. SRAM later introduced their own 2×10 drivetrain for the same reason. X11 is the natural extension of that—hopefully eliminating any front chainring related problems while still offering the gearing range you’ll need. I’ll have an group X11 on my personal race bike for the next Cape Epic.
The only disadvantage is that it creates yet another standard, which means shops need to stock more freehub bodies to cover the demands of their customers.
White Industries: The advantage is that our freehub body is made out of titanium so you have the benefit of light weight without sacrificing strength or integrity like with an aluminum freehub body. We do not detect any disadvantages to the new system.
BIKERUMOR: What are some of the design differences you had to consider?
American Classic: I had to precisely calculate the spacing. I used deep hard coating on the exterior of the body. My 6 pawl hub design is particularly well suited to the hi torque of the largest sprocket in the XD system (meaning when the rider is in the super low gear and using the largest sprocket in back, it puts a huge torque load on the hub). Other hubs cannot withstand this kind of torque well. – Bill Shook, Company President & Engineer
Chris King: Our concern is in ensuring that an XX1 compatible Chris King product will meet the extreme demands of today’s mountain bike riders. XX1’s current freehub body configuration poses a particularly interesting challenge and one that we will need to be solved to our standards before we release a Chris King compatible version. We will continue to research XX1 compatible Chris King rear ISO disc hubs until we are confident that we have found an engineering solution that satisfies the high standards of precision, performance, and durability that are characteristic of every Chris King component.
Author’s Speculation: Chris King makes all of their own bearings and bearing races in house. It wouldn’t come as a surprise if they need to develop a new bearing size to fit inside the slightly narrower outside diameter of the XD driver or design an alternative solution to maintain their current bearing sizes. Scroll up and stare at the comparison of the XD and standerd I9 drivers for a visual.
Crank Brothers: We can retrofit the hub onto our current wheel line. The endcap and the freehub were completely different due to the unique design of the XX1 cassette. Everything else remains unchanged.
DT Swiss: DT worked closely with SRAM to spearhead the new cassette/freehub body interface, so we were at the ground level as the groupo developed. Some of the bigger design parameters that out engineers faced were to accommodate the specific needs inherit to the XX1 cassette’s size, range, and design. In brief:
- Developing an interface that addresses the load placed on the largest cog. Lots of torque required a stout interface.
- Reducing the freehub body on the opposite end to accommodate the smallest 10tcog. The smaller diameter cog just couldn’t fit on the same diameter freehub body like an eleven can..
-It was desired to fit 11 cogs within the same real-estate without altering rear triangle spacing or requiring wheel re-dishing, everyone is just getting up to speed with 12×142!
-Finding a simple solution way to affix the whole cassette to the freehub body.
-Developing a design that doesn’t sacrifice durability in the name of other design elements.
DT had a huge advantage incorporating our star ratchet driver system into the XD Driver design. It’s a design that’s compact, simple, and super adaptable. It’s a design that lends itself well to different applications. The other huge benefit being that our star ratchet system has withstood the test of time and has proven durable in the field. In other words, we had a very solid foundation to build the shell around from there, all the other pieces fell into place.
E13: Other than bearing tweaks, we were able to adapt our free hubs to the new design pretty easily. One of the main differences with the new groupo that we have been concerned with is the growing size of rear cassette cogs and how much force they are able the deliver to the rear hub under load. We looked carefully at this when we launched our wheels last year and have had all positive results from test riders and machine testing.
Easton: The biggest design difference between the SRAM XD and our SRAM 9/10 speed mountain cassette body is packaging. We wanted to use our current hub/axle design, but because of the wider bearing spacing necessary for the SRAM XX1 cassette body we weren’t able to make the endcaps and their o-rings engage in the same manner as before. This necessitated an additional o-ring on the inner bearing spacer to ensure that the cassette body will stay in place when your wheel is off the bike.
Additionally, the endcaps are substantially different. They had to get smaller in almost every dimension to be able to fit within the XX1 cassette. We also wanted to keep some form of protection for the bearings. This was achieved by a thin flange that helps to seal the cassette locking tube from dirt and debris. The result of all these changes is a smaller, lighter freehub that maintains the same durability and functionality as our old SRAM 9/10 speed bodies but with all the benefits of SRAM’s XX1 11 speed cassette.
Hadley: The only design differences between the XD and the Shimano is that the XD has a smaller diameter at the end of the freehub which reduces the bearing size, which slightly reduces the axle size at the very end of the drive side . This was a simple design change.
Hope: Due to the quality of the bearing we use in our cassettes it didn’t really cause any issues going down to such a small outer diameter on the cassette.
I9: The basic interior layout of our freehub design and our current axle system were both compatible with no changes, so it was a relatively easy process to accommodate the external dimensions. SRAM offered great support for the design process by providing detailed prints and specs on the design, which was helpful as well. We did have to place the outboard inner freehub bearing partially outside of the shell (the same configuration SRAM uses on some of their XX1 freehubs) in order to accommodate the external specs. The alternative would have been to downsize our bearing spec. which would have compromised bearing durability. Functionally, this doesn’t compromise the design, and it provides great support for the XX1 inner cassette tube, providing the cassette added stability.
Mavic: In terms of manufacturing, the main thing was making sure it’s durable and well-supported by the internal bearings to manage the loads of the large cogset. But the ITS-4 internal architecture is already suited to the new design. So it wasn’t too hard to engineer for XX1.
Profile: I can’t imagine that we’ll have much trouble integrating it into the 6 pawl Ultradrive engagement design we use on all of our Elite hubs. When you can take it from the machine and install it onto a bike in minutes, it’s a lot easier to sort out any potential hiccups than it is to wait for someone else to make them for you, ship them to you, etc. We know right away if we need to make a bearing bore .015mm larger or whatever the case may be.
Stan’s No Tubes: We had to offer six different conversion kits due to the variety of end caps we offer. It was a pleasure to work with SRAM in the design of this new product.
Ritchey: With any freehub body design you have to pay close attention to tolerances, surface treatments, bearing size and placement and sealing design and technology, but we’ve been making world-class hubs long enough that this is just part of the process. Also, the larger 42t cog on the X11 cassette provides more clearance between the rear derailleur and the spokes when you’re in the lowest gear, which means you can design less dish in your rear wheel for a stronger wheel. Ritchey wheels employ an OCR (Off Center Rim) design to reduce dish, so we’re already able to take advantage of this.
White Industries: SRAM was very helpful with the intellectual property, and the transition to bring this new design to the market place was fairly seamless.
Editor’s Note: We have inquiries out to Hayes and a couple others, and will update the post if/when we get information. Word on the street is Hayes is working on it.
Specialized has chimed in to say their Control Race, Control Trail and Traverse wheels are compatible with DT Swiss’ XX1 Driver Body since they use DT’s hub internals.
Hadley Racing didn’t respond to our inquiry for this article but when asked back in September stated – “There are plans, I can’t give you a firm date as to when it will happen.” They’re doing it! Responses added above.
SUNringle couldn’t provide any information at this time but the product team “is looking into it.” We’ll let you know as they update us.
Rolf Prima: “Our Ralos (29”, 27.5” and 26”) and Ralos CXC (29”) models will be available with an XX1 compatible freehub starting in early February.”
Reynolds: “We are currently working on an XX1 conversion kit for our current 2013 26AM carbon, 29r carbon, 650b carbon, 29r alloy and 650b alloy. We are expecting availability around late March and MSRP will be around 90.00 usd.
Earlier Reynolds MTN wheels equipped with earlier Reynolds’ hubs will not be compatible with XX1…only the newer versions. If a customer has an older Reynolds wheel we would work with them to relace their wheel. The customer would need to supply a hub, pay for shipping each way and for a small fee (for labor and spokes), Reynolds will work with the customer to get the wheel up to date. ”
KORE: New XX1 freehub bodies just announced, full post here.