You need to see this... (new hub design)

[ergott]

So some of you may know that Alchemy Bicycle Works (Jeremy) has been extremely hard at work making a new hub design. Well, the front hubs are rolling out (pun intended). I have the first one sent out here and I must share with you. I'm very fair in my evaluation of products and I will say this. This is the best front hub out there bar none. The rear is still in the works, but I fully anticipate them to rise to the same standards. Here are the details.

The flange spacing is wider than any other hub available.

Center to flange spacing is 39.6mm (measured) so total flange width is 79.2mm. So, you may say? Well here are some comparisons:
Tune - 70.4mm
WI H2 - 71.6mm
DT - 74.7mm (previous best)
A wider flange spacing will make a wheel laterally stiffer without changing any of the other components. It's wide enough that I would lace the hub radial heads out and they will be as laterally stiff as heads in on a Tune hub.

The bearings are as close to the dropouts as possible. This will have a more dramatic effect on the hub stiffness than anything else. The bearings are sitting outboard of the flanges!

Bearing quality is at the top of the pile with Enduro ceramic hybrid bearings stock.

The tolerances of the hub are excellent. One of the bearings will be bonded so there is no hub play even though there is .2mm tolerance built in. This will prevent the bearings from being side-loaded so bearing will life will be the best possible.

At 58g (my copy), the weight is competitive with the lightest hubs out there that aren't designed to be this strong or durable.

Servicing is easy. The axle can be pressed out with a 5mm bold inserted into one side. The axle is pressed through and that's it.

I can't wait to build this hub into the Reynolds SDV 66mm rim waiting for it! You can expect there to be a logo once production is in full run. The first batch was unlabeled.

Thanks for looking!

http://websites4ever.com/ergott//images/alchemy_1.jpg
http://websites4ever.com/ergott//images/alchemy_2.jpg
http://websites4ever.com/ergott//images/alchemy_3.jpg
http://websites4ever.com/ergott//images/hub_comparison.jpg

[Louis]

Is it compatible with most of the major fork designs out there? Super-wide flanges could have interference problems.

[pdxmech13]

how long did it take him until this final version was completed.

[saab2000]

Will we finally be able to build a Neutron-equivelant wheel out of over-the-counter components?

[norman neville]

where are they made?

what will the logo say?

[Too Tall]

Gosh that's neat. So I am guessing these are optimized for modern deep(er) carbon and aluminum (front) rims yes? Velly intelesting.

[ergott]

Logo design not finished.

Made in the US

Compatible with all forks

Jeremy has bee at this for years. The prototype/preproduction runs have been going on for over a year now. He has been testing them with local high mileage riders/racers for a while now. Jeremy is one of the smartest guys I know.

[Smiley]

Jeremy is building my fixee wheel set with this hub in Silver. Jeremy is a freaking bright guy and he knows wheels.

[norman neville]

Made in the US

Compatible with all forks



it's all good.

nice.

[Elefantino]

Will atmo use them on his bikes?

[Tobias]

The tolerances of the hub are excellent. One of the bearings will be bonded so there is no hub play even though there is .2mm tolerance built in. This will prevent the bearings from being side-loaded so bearing will life will be the best possible.Eric, please explain what this means. I can't follow the side load thing, and can't visualize what is done if the bonded bearing needs replacement.
I like the simple and very clean look.

[ergott]

Eric, please explain what this means. I can't follow the side load thing, and can't visualize what is done if the bonded bearing needs replacement.
I like the simple and very clean look.

If you make the hub shell so you have to really press in the bearing hard, it does compress the bearings enough to cause some drag. It is better to design the hub so the bearing presses in with less pressure. There is a total of .2mm tolerance built in between the hub shell and where the bearings ride. With one bearing bonded the hub won't potentially shift that .2mm. Without that .2mm build into the system, the hub would have to be perfectly machined every time and nobody can consistently machine the better tolerances than that.

[Tobias]

Eric, I hate to admit it, but I’m still confused.

It sounds like you are talking about extra radial clearance so the bearings’ outer race isn’t placed in compression when pressed into the hub shell. However, I doubt I’m understanding it correctly because if that is the case and only one bearing is bonded, then the other one would be too loose.

The other thing that I’m getting confused on is the 0.2 MM of clearance which sounds like it may be axial, not radial. Is that the case? Which is it?

In any case, when a side load is applied to the wheel, don’t one or both bearings have to resist the axial load? How does bonding prevent the bearings from being side loaded?

I know just enough to know I’m not getting what you are saying. If you can clarify one more time I’d appreciate it. Thanks.

[jthurow]

Any idea when he'll have a rear hub? And how much these are gonna cost?

jimi

[ergott]

Eric, I hate to admit it, but I’m still confused.

It sounds like you are talking about extra radial clearance so the bearings’ outer race isn’t placed in compression when pressed into the hub shell. However, I doubt I’m understanding it correctly because if that is the case and only one bearing is bonded, then the other one would be too loose.

The other thing that I’m getting confused on is the 0.2 MM of clearance which sounds like it may be axial, not radial. Is that the case? Which is it?

In any case, when a side load is applied to the wheel, don’t one or both bearings have to resist the axial load? How does bonding prevent the bearings from being side loaded?

I know just enough to know I’m not getting what you are saying. If you can clarify one more time I’d appreciate it. Thanks.


.2mm of lateral clearance. There is no radial clearance. They bearing press easily into the hub.

[Tobias]

.2mm of lateral clearance. There is no radial clearance. They bearing press easily into the hub.Thanks Eric, I think I get it better now.
It sounds like bonding one bearing makes that side more likely to take the lateral forces in both directions. The other side should take much less lateral forces.
The main advantage I see to this set up is that the bearings can be made to slip into the hub more easily to reduce compression -- as you noted above -- and that by bonding one side the outer race of the bearings won't slide that .2MM back and forth which could wear the hub shell.
Loose fit may reduce rolling resistance as you claim, but I don't see how it reduces side loads in any way. If anything it appears to place it all on one bearing.
It'll be interesting to see how much easier the bearings spin due to less compression. I wouldn't have thought it mattered much, but apparently some think so.
Thanks again for the clarification.

[Climb01742]

jeremy is a very very nice guy, and great to do biz with. hope this works out gangbusters for him. may this nice guy finish first. :beer:

[MRB]

Eric,
Thanks for posting. I enjoy seeing the entrepreneurial side of people coming out. Especially when it means a better (and safer) product is coming to market. I hope to buy a set of wheels made by you someday!

the hub looks a lot like the hugi, which is an great hub.

[jthurow]

Roues Artisanales has a sneak peek at Jeremey's new hubs (http://www.rouesartisanales.com/article-17308491.html). mmmm, silver...

jimi

[bobscott]

One of the big selling points of the front hubs is the bracing angle produced by the wide flange placement.

But looking at the rear hub prototype, it doesn't look like this approach was taken on the rear hub. It appears that the flanges could have considerably wider placement.

What design element am I missing here?

bobscott

[jthurow]

I think it is as far as possible to the drive side. If the non-drive side flange gets closer to the dropout, I think it messes up the dish and makes the spoke tension between the two sides more unequal.

jimi

[musgravecycles]

Lol, I saw that but wasn't about to say anything... If you search the archives you'll find that we had a major. . . uhhh. . . "discussion" ;) on this very thing a couple of years ago...

[RPS]

......snipped......There is a total of .2mm tolerance built in between the hub shell and where the bearings ride. With one bearing bonded the hub won't potentially shift that .2mm. Without that .2mm build into the system, the hub would have to be perfectly machined every time and nobody can consistently machine the better tolerances than that.It would seem that machining could be done more accurate than .2 MM. Isn’t that about 8 thousands of an inch, many times more than many engine parts are machined to?

I have three sets of Speed Dream wheels with front hubs that are somewhat similar, and although I have no idea what the actual tolerances are the front wheels definitely have no perceptible lateral play. When the bearings are in good shape the wheels are rock solid.

I replaced the bearings on one front wheel and it appears the outer races either bottom out against the hub shell or are kept from moving laterally (within the machining tolerances) by friction. Either way it all works fine – even on a tandem. I like the simplicity and ease of maintenance.

[ergott]

One of the big selling points of the front hubs is the bracing angle produced by the wide flange placement.

But looking at the rear hub prototype, it doesn't look like this approach was taken on the rear hub. It appears that the flanges could have considerably wider placement.

What design element am I missing here?

bobscott


I think that rear is tandem spaced. The center to right will be over 19mm and the total flange width is similar to Tune.

[stevep]

no offence but front hubs are no big deal.
it all means nothing.


the cassette hub is the trick.

[93legendti]

So some of you may know that Alchemy Bicycle Works (Jeremy) has been extremely hard at work making a new hub design. Well, the front hubs are rolling out (pun intended). I have the first one sent out here and I must share with you. I'm very fair in my evaluation of products and I will say this. This is the best front hub out there bar none. The rear is still in the works, but I fully anticipate them to rise to the same standards. Here are the details.

The flange spacing is wider than any other hub available.

Center to flange spacing is 39.6mm (measured) so total flange width is 79.2mm. So, you may say? Well here are some comparisons:
Tune - 70.4mm
WI H2 - 71.6mm
DT - 74.7mm (previous best)
A wider flange spacing will make a wheel laterally stiffer without changing any of the other components. It's wide enough that I would lace the hub radial heads out and they will be as laterally stiff as heads in on a Tune hub.

The bearings are as close to the dropouts as possible. This will have a more dramatic effect on the hub stiffness than anything else. The bearings are sitting outboard of the flanges!

Bearing quality is at the top of the pile with Enduro ceramic hybrid bearings stock.

The tolerances of the hub are excellent. One of the bearings will be bonded so there is no hub play even though there is .2mm tolerance built in. This will prevent the bearings from being side-loaded so bearing will life will be the best possible.

At 58g (my copy), the weight is competitive with the lightest hubs out there that aren't designed to be this strong or durable.

Servicing is easy. The axle can be pressed out with a 5mm bold inserted into one side. The axle is pressed through and that's it.

I can't wait to build this hub into the Reynolds SDV 66mm rim waiting for it! You can expect there to be a logo once production is in full run. The first batch was unlabeled.

Thanks for looking!

...[/img]
Very cool. Jeremy's wheels are on my new Spectrum.

I am looking forward to purchasing a set of wheels with these hubs.

[ergott]

no offence but front hubs are no big deal.
it all means nothing.


the cassette hub is the trick.


If he put that much effort into the front, imagine the potential of the rear hub which he's really sweating over. It will be good stuff.

[Dave]

It would seem that machining could be done more accurate than .2 MM. Isn’t that about 8 thousands of an inch, many times more than many engine parts are machined to?

I have three sets of Speed Dream wheels with front hubs that are somewhat similar, and although I have no idea what the actual tolerances are the front wheels definitely have no perceptible lateral play. When the bearings are in good shape the wheels are rock solid.

I replaced the bearings on one front wheel and it appears the outer races either bottom out against the hub shell or are kept from moving laterally (within the machining tolerances) by friction. Either way it all works fine – even on a tandem. I like the simplicity and ease of maintenance.

That little exerpt is not clear to this (former) machinist. Perhaps a digit was slipped? .2mm is not precise at all, but .02 (.0008 inch) is, in most cases.

When manufacturers of machine tools talk about about the ability of their machines to hold close diameter tolerances, we get into much smaller values than that, like + or - .0025mm (.0001 inch). This would be typical for a good Hardinge CNC lathe.

[ergott]

Will will check with back with Jeremy on the later specs of the bearing placement. I'm probably getting my numbers wrong. You will hear back from me or possible I can talk Jeremy into elaborating for us.

[J.Greene]

If he put that much effort into the front, imagine the potential of the rear hub which he's really sweating over. It will be good stuff.

I've never had hub or wheel problems (knock on wood). Does the world really need another hub?

JG

[RPS]

That little exerpt is not clear to this (former) machinist. Perhaps a digit was slipped? .2mm is not precise at all, but .02 (.0008 inch) is, in most cases.

When manufacturers of machine tools talk about about the ability of their machines to hold close diameter tolerances, we get into much smaller values than that, like + or - .0025mm (.0001 inch). This would be typical for a good Hardinge CNC lathe.That's kind of the point I was raising. With a little accuracy the amount of lateral play is very minor unless the designer is concerned about the hub shell wearing out due to bearing movement. And we should keep in mind the bearings are not only pressed in place, but that lateral loads on a bicycle wheel are normally very low; particularly at the front.

[Jeremy]

Hi all,

Eric asked me to chime in. The 0.2mm is not a diameter tolerance. Diameter tolerances must be much more precise than that. In fact, the 0.2mm dimension is not a "tolerance" at all. It is a design dimension. The distance between the bearing stops in the hub-shell is 0.4mm shorter than the distance between the bearing shoulders on the axle. One bearing bore uses a 0.2mm spacer between the bearing and the stop. This bearing is bonded with sleeve retainer into the shell. When the axle and other bearing is installed, there should be 0.2mm of space between the inside edge of the bearing and the hub-shell bearing stop. This is the 0.2mm dimension that Eric mentioned.

The reason for this is to eliminate the tendency of the Q/R skewer to impart asymmetric lateral loads (one race loaded relative to the other race, which results in drag) on the bearing. In addition, the diameter tolerance of the bore is designed to be a light press fit for the bearing. The reason for this is that a tight press fit causes compression of the bearing assembly which increases drag on the bearings that are commonly used for bicycles. With a light press fit tolerance, it is a good idea to bond the bearing in place. However, with a shouldered axle design it is only necessary to bond one side. I chose a thicker section bearing than most other lightweight hubs use for two reasons. First, the load capacity of the bearing is much higher because of the larger diameter balls used in thicker section bearings. Second, the thinnest section bearings are even more prone to binding caused by a tighter fit.

SteveP, I agree that front hubs are simple. However, bearing placement, flange placement and bearing capacity all affect the ultimate performance and strength of the wheel. I have tried to optimize all of those dimensions while keeping the hub light and strong. Still, the rear is the harder challenge and I am happy with the progress so far. As to flange placement, the rear hub will have relatively widely spaced flanges (60mm), and I have also focused on optimal drive side flange placement. This will create good non-drive spoke tension and wide bracing angles on both sides.

Cheers,
Jeremy

[ergott]

That's what I was waiting for! Thanks. You make 'em, I'll build 'em (of course so will you).

:beer:

[stevep]

i look forward to seeing a pr.
should be a challenge.

[Jeremy]

And we should keep in mind the bearings are not only pressed in place, but that lateral loads on a bicycle wheel are normally very low; particularly at the front.

While it is true that lateral loads on a bicycle hub due to riding forces are low, the quick release force can create enormous side loads on the bearing. You can confirm this by doing an experiment. Take a standard cup and cone hub and adjust it so that there is minimal drag and no play. Then clamp it properly in a fork and rotate the hub shell to "feel" the bearings. You will notice that the drag goes up enormously. This is the reason why cup and cone hubs are supposed to be adjusted with a little play. The Q/R force eliminates this play. If you adjust a standard cup and cone hub without this play, the Q/R force creates a lot of drag (and premature failure of the races and cones).

The same thing happens with cartridge bearings. If you load one race relative to the other, even a tiny bit, it causes drag and premature failure of the bearing. There are many ways to deal with this. The most common is to use a threaded axle and threaded lock-nuts. This system works well but it requires that the bearing placement is in-board enough to accommodate the adjusting nuts. This creates additional space between the bearing and the dropout. This requires a stiffer and heavier axle to achieve the same level of stiffness that can be achieved with a lighter axle and wider bearing placement. In addition, threads create a stress riser which require a thicker wall to offset.

Finally, holding lateral tolerances is not as simple as you suggest. A tolerance has to be held relative to something else. In the case of hub shells the depth of the bearing bore is usually held relative to the outside of the shell. So, even with a tight lateral tolerance of +/- .001", the tolerances can "stack up". If the tolerance between the bearing bores in the hub shell and the tolerance between the shoulders of the axle "stack up" the wrong way, the Q/R force can cause binding of the bearing system. The 0.2mm dimension in my design is not a "play" dimension. It is there to prevent the possibility of the tolerances "stacking up" and causing drag.

Cheers,
Jeremy

[J.Greene]

If you adjust a standard cup and cone hub without this play, the Q/R force creates a lot of drag (and premature failure of the races and cones).

Cheers,
Jeremy

If your hubs last 1/2 as long as a cup and cone Campagnolo hub with perfect adjustment and no slack you will have done well.

JG

[Jeremy]

If your hubs last 1/2 as long as a cup and cone Campagnolo hub with perfect adjustment and no slack you will have done well.

JG

JG,

I agree! The cup and cone design is excellent and I certainly did not mean to impugn it. I try to avoid using comparative adjectives like "best" and "better" because everything in life involves trade-offs. The beauty of it is that everyone values different things, in different proportions.

Cheers,
Jeremy