ORC hubs are in! First impressions...

[GuyRichard]

Hello all,

We've received (finally!) some ORC hubs from the kind folks at Alchemy Wheelworks. These are pre production hubs, hopefully that last run of useable prototypes before Alchemy moves into regular production. They're only releasing a handful of these, and Fairwheel's supposedly got the only few that aren't presold or slated for wheelbuilds. For the masses still waiting on the ORC, Alchemy now has a projected release of mid to late January. Though given the long delays associated with this hub's release, no one's making any promises at this point. The good news, though, is that Alchemy should have both ELF and ORC hubs available in black, silver.... and red. Also, Jeremy at Alchemy has made specific redesigns to ensure compatibility with Campy 11 speed cassettes without compromising the hub's original design.

After pulling the hubs out of their box, first thing I noticed is how effortlessly the axle spins. In terms of initial bearing drag, probably the best rear hub I've ever felt. I'd attribute that to the larger bearing sizes and excellent machining tolerances. From my hand, the hub went straight to the scale. 222 grams – quite a bit more than the 205 grams originally projected, but a few less than the claimed 225. We knew this was coming, and suspect that most of the weight gain has to do with the removal of the ceramic bearing spec. Alchemy is also no longer using ceramics in the ELF hub. This decision was made partly to keep with the original planned MSRP of $420. Ceramic upgrade will be available for the ORC for an additional $100. Moving on, the next step was pulling the ORC's axle to get a view of the internals. Once the cap was removed, I was able to easily slide the axle out by hand, another testament to Alchemy's careful and accurate machining. The freehub body, however, would not budge. Further disassembly seemed like a bad idea.

Of course Jason would have none of that. On the phone with Jeremy only a few minutes later, he's asking what we need to extract the freehub body and fully disassemble the hub. Jeremy advises against taking the hub apart, then proceeds to explain exactly how to do so. Ten minutes later and twenty five cents poorer, we've got it all apart and photos taken for your viewing pleasure.

So why is the ORC so great? It's light, but not that light. It's not astronomically expensive, but it sure isn't cheap. Well, I see it as a pure performance product. The fact that it's fairly lightweight is more of a bonus. This is a hub that I would personally want to (and will) ride because it might just make my ride more enjoyable. The ORC's hub design is all about stiffness and efficient torque transfer. All the little details that make this hub special contribute in some way to these paired traits. The cassette body is attached directly to the shell with a massive 6807 bearing, and internally attached to the axle with a standard size 6803 bearing. By attaching the freehub to both hub shell and axle, the whole system becomes much stiffer and more structurally sound. Additionally, there's a reinforcement sleeve which essentially increases the axle diameter at the point where it enters the hub shell. The axle itself is relatively large at 17mm, stepped up to 20mm at the center sleeve. Finally, the diameter of the hub barrel is pretty large in diameter, which also helps to increase overall stiffness. Also worth noting is that the freehub mechanism is equipped with three simultaneously engaging steel pawls on a drive ring with 36 engagement points, a few more than most hubs. This should allow for slightly quicker and firmer engagements under pedaling force.

The ORC will be available in both Campagnolo and Shimano versions, and as mentioned, will have no problems with 11 speed cassettes. Changing the freehub body from one to the other is possible, but not very easy. The freehub body and axle end cap will need to be changed, and the wheel will require redishing. The advantage, of course, is having a hub that makes no compromises with flange positions and non drive spoke tension.

For wheelbuilding nerds like myself, here's a writeup from Jeremy at Alchemy regarding the hub's flange dimensions:

The drive side flange is quite large. This reduces stress on the spokes (from pulling force) and increases the efficiency of torque transfer.
Wheel building dimensions are very important to me. Simplistically, flanges spaced further apart create a stiffer and stronger wheel. However, because multi speed drive-trains require sufficient space on the drive side for the gears, and the over locknut dimension (space between the dropouts) is fixed, no modern hub can have symmetrically placed flanges (center right = center left). Thus, the angle from the drive side flange to the center of the rim is smaller than the angle from the non-drive side flange to the center of the rim. This creates what is called "dish". Because of this, the non-drive side spokes must be under a lower tension than the drive side spokes in order for the rim to be centered between the dropouts. This relationship is a simple linear function. Specifically, RBA (right bracing angle) x tension = LBA (left bracing angle) x tension. So, if the RBA = 4 degrees and the LBA = 8 degrees and the drive side tension = 110Kgf, non drive side tension = 55Kgf. While wider flanges produce stiffer and stronger wheels, at some point, the non-drive side tension becomes too low to maintain tension during the low tension cycle that occurs while riding the wheel. So, it is important to balance flange width with non-drive side tension. If you want to increase non-drive (relative) tension you can achieve this by moving the left flange further right (which decreases the LBA) or moving the right flange further right (which increases the RBA). However, moving the left flange further right lowers overall stiffness and strength to achieve higher non-drive side spoke tension. So, you trade a good for a bad. The better way to do it is too move the right flange further right which increases the RBA, the flange width, and the non-drive side spoke tension. All of which add to the strength and performance of the wheel. So, my design has widely spaced flanges and a larger center right dimension, which produces a stiffer and stronger wheel and good non-drive side tension.

Perhaps one of the major downfalls of the ORC is its serviceability. We had a hard enough time getting it apart, and I would wager that most shops' service departments don't have the kind of hub tools we've got. User service is pretty much out of the question. One thing I will add is that I'm optimistic of the ORC's durability, mostly for the quantity (5) and larger size of the bearings used. So I'm guessing it won't need to be serviced that often.



~Richard

[Jeffr]

Thanks for the report Richard. I've been interested to see what was going to happen with these. They look like a ruggedized tune hub. How much does the flange spacing actually differ from tune? Does the campy version have smaller bearings in the freehub?

Also, to my untrained eye it looks like some drillium could lighten it up. I wonder if there is a possibility of lighter versions in the future with more expensive machining or a carbon axle? I imagine Jeremy has other tricks up his sleeve. Anyhow, I'd definitely consider these for my next all around wheelset.

[madcow]

Nice review Richard, I think it was well written but would like to hear what others think as well. Richard has more information than he's shared, so if you have questions feel free to challenge him with them.

[GuyRichard]

...I wonder if there is a possibility of lighter versions in the future with more expensive machining or a carbon axle? I imagine Jeremy has other tricks up his sleeve.

[Jeffr]

Is that a young ll cool j? He's going to be using these hubs for his cat-5 debut race? How exciting. Mama say ride yo' bike. I'm gonna ride yo' bike.

[GuyRichard]

Thanks for the report Richard. I've been interested to see what was going to happen with these. They look like a ruggedized tune hub. How much does the flange spacing actually differ from tune? Does the campy version have smaller bearings in the freehub?

Jeff,
The Orc does have some similarities to the Tune, but it's really a whole different beast on the inside. Where the similarities do exist, the Orc is much beefier. I think the two are really in a different class, though. I still like the Mag 180 as a simple lightweight hub.

I just measured the center to flange on a Mag 180 and compared it to the Orc:



We don't yet have any campy versions of the hub, but I don't see any reason why they would use a different size bearing the in freehub.

~Richard

Edit: Jeremy corrected me on my numbers. See my post below.

[Jeffr]

So interestingly the total flange distance is smaller on the orc but closer to a 2:1 ratio so the spoke tensions should be better on the NDS.

[Zak]

Does anyone know how the orc-hub compare the new Ligero hubs?

[GuyRichard]

Jeremy corrected me on my flange number measurements. It turns out the the Orc's overlocknut dimension is actually 131 mm, where I had assumed that it was the standard 130 mm. Also, the flanges are angled; 3 degrees on the right and 6 degrees on the left. So my right center to flange measurement was off by .7 mm. Jeremy also provided the numbers for the Orc with a Campy freehub. To be fair to the Mag 180, I remeasured the Shimano version as accurately as I could, and also measured a Campy version. Here's my revised table:



~Richard

[Adrien]

Thanks for the report Richard. I've been interested to see what was going to happen with these. They look like a ruggedized tune hub. How much does the flange spacing actually differ from tune? Does the campy version have smaller bearings in the freehub?

Jeff,
The Orc does have some similarities to the Tune, but it's really a whole different beast on the inside. Where the similarities do exist, the Orc is much beefier. I think the two are really in a different class, though. I still like the Mag 180 as a simple lightweight hub.

I just measured the center to flange on a Mag 180 and compared it to the Orc:



We don't yet have any campy versions of the hub, but I don't see any reason why they would use a different size bearing the in freehub.

~Richard

That's a pretty good review, I can't wait to have one in hand. The 6807 bearing in the middle indeed sounds to be creating a very strong/stiff system. That's bad this solution comes with a so heavier weight.
What kind of tests were performed to show any difference with others hubs?

Regarding the table you show, you compare the Campa Tune hub with the Shimano Orc, it doesn't make sense. Indeed the Shimano Tune hub drive side width actually is 19mm, the Campa being 17mm. As explained in Jeremy's quote, because of the cassette's width, there is no way to increase further the drive side bracing angle. So 19mm is the maximum for a Shimano system, 17mm being the max. for the Campa system unless you cheat on overall width.

So far, I only had the front ELF hub in hand, I think the good thing is how Jeremy optimized the stiffness and smoothness of the hubs.
That's really a big plus over the others hubs of the market, at least for the front hub. The rear one sounds a bit overweighted but for a first version that's pretty cool anyway.

As said above, I would really love to see a lab test proving the stiffness gains of the rear. The beefed internals certainly comes with durability and strength beside the smoothness, but in term of stiffness it's really not predictable so easily. Bearing size and axle diameter play a very small role, if any, in the whole wheel.

I'll contact Sarah at ABW soon

[GuyRichard]

That's a pretty good review, I can't wait to have one in hand. The 6807 bearing in the middle indeed sounds to be creating a very strong/stiff system. That's bad this solution comes with a so heavier weight.
What kind of tests were performed to show any difference with others hubs?

Regarding the table you show, you compare the Campa Tune hub with the Shimano Orc, it doesn't make sense. Indeed the Shimano Tune hub drive side width actually is 19mm, the Campa being 17mm. As explained in Jeremy's quote, because of the cassette's width, there is no way to increase further the drive side bracing angle. So 19mm is the maximum for a Shimano system, 17mm being the max. for the Campa system unless you cheat on overall width.

So far, I only had the front ELF hub in hand, I think the good thing is how Jeremy optimized the stiffness and smoothness of the hubs.
That's really a big plus over the others hubs of the market, at least for the front hub. The rear one sounds a bit overweighted but for a first version that's pretty cool anyway.

As said above, I would really love to see a lab test proving the stiffness gains of the rear. The beefed internals certainly comes with durability and strength beside the smoothness, but in term of stiffness it's really not predictable so easily. Bearing size and axle diameter play a very small role, if any, in the whole wheel.

I'll contact Sarah at ABW soon

Adrien,

The measurements shown are all flange center to hub center, not outside flange to hub center. I think that's where the confusion is.

Also, I'm not sure if Alchemy has peformed any tests to quantify or compare hub stiffness. Maybe Jeremy can chime in...

~Richard

[Cheers!]

I wonder why Jeremy went with a pawl system rather than a ratchet type system. I personally would have preferred a ratchet system.

[Ligero]

Does anyone know how the orc-hub compare the new Ligero hubs?

My new version 2 hub will be very similar to the Alchemy rear hub. Mine will have a 17mm axle and not the 17/20mm stepped axle of the Alchemy. I will have the same type of large diameter bearing that is pressed onto the freehub body but I am using 4 bearings instead of 5 like Jeremy is. The major difference between mine and his is the flange spacing. My hub can only be used as a 24h rear laced with 16 drive spokes and 8 non drive spokes. I have designed the flange spacing around the 2 to 1 lacing pattern and it is so wide it would not work at all in a conventionally laced pattern. The center right measurement on my hub is 18.5mm and the center left measurement is 50mm.

The only reason I can run the extremely wide non drive side flange spacing is because of the 2 to 1 lacing. When you double the drive side spokes it doubles the tension of the non drive side spokes. Because of that I could move the flange very far out and still have 75% tension on the non drive side compared to 45 to 55% of a conventional laced wheel.

[pritchet74]

Troy - what will the weight be of your V.2 rear hub?

[alienator]

I'd like to see numbers, or at least a first order approximation, of the improvement in "torque transfer." Any torque lost in the wheel--excluding tire and tube--can only be a function of rim flex, spoke stretch/flex, and flex in the hub. Off the cuff, it seems that sum would be very small. Very small.