06 July, 2010

Hub News


The photo is of our VO freewheel hub. They use high quality Japanese bearings. The spoke holes on the drive side are slotted so broken spokes can be easily replaced with the freewheel in place, but we are still doing strength testing on this feature. We hope to have them for sale early this fall in 126mm and 130mm spacing. 120mm spacing is also possible if there is demand.

The VO flip-flop hub prototypes are also here, but the design is undergoing some cosmetic modifications that may require a bit of new tooling, so no ETA yet.


The pictured quick release is something we're still thinking about. Do you like it?

The VO cassette hub is taking a little more time to develop than we thought. I doubt we'll have them finished before late fall.

I recently mentioned a new dynamo hub design that I thought was revolutionary and might make existing high end dyno hubs obsolete. We have a production-ready sample that we'll be testing over the next few weeks. But I can already tell you that the build quality looks very impressive and, if my calculations are correct, it will cut overall rolling resistance by more than 50% compared to any other (production) dyno hub that I'm aware of, while maintaining the same 3w/6v output. If all goes well we should have them in around 3 months. The cost will be considerably lower than existing high-end dyno hubs. We do want to be clear that this is not technology developed by VO (we're not that smart), but from a small company we ran into almost by accident.  I'm sure that you have questions about them, but those are all the specs we'll reveal for now; sorry.

45 comments:

Anonymous said...

I'm betting Chris is introducing the world's first dynamo hub equipped with superconducting magnets...the liquid nitrogen supply will make for an interesting challenge on those long brevets.

Justine Valinotti said...

I'm a little leery about those slotted spoke holes. Years ago,I had a hub with them. I had a lot of broken spokes. Then again, it wasn't exactly a high-end hub; I forget what brand it was.

dr2chase said...

Regarding dynamo hubs, it is possible to get much more energy out of the "old style" hubs that we have now, by extracting it more carefully. The 6V/3W designation assumes a half-amp of current, which is far from their peak delivered power.

For the high-end Shimano dynamo hubs (3d71), peak power comes at about 1/5 amp, and much higher voltage (e.g., 50V at 20mph, times .2A, gives 10W). And since drag is proportional to current, lower drag.

The main difficulty is in designing/buying a switching regulator that will cope with the wide range of input voltages and sometimes very-high voltages. The higher the tolerated voltage, the better, because the only way to limit the voltage is to bleed power off.

See pilom.com for hub dynamo power measurements.

Here's my attempts in this direction, using a canned LED regulator; the hard voltage limit is 32V, but it seems to activate the clamp before then. 20-25V is a typical voltage, implying 4-5 watts from a "3W" dynamo.

I'm working on another one (60V limit), but these things take time, and there's software in it, which makes it extra fun.

Anonymous said...

Slotted spoke holes date from a time long ago when spoke and rim quality was much inferior to modern parts. In a stronger modern wheel with adequate (i.e. higher)and more uniform spoke tension, these slotted holes serve little to no purpose.

The large open slots would probably not support the spoke elbow as well as a well-sized regular drilled and chamfered hole. The loose fit would probably lead to MORE broken spokes !

To me this falls squarely into the realm of blindly copying a past design in order to follow fashion instead of function.

I guess that re-creating an obsolete rear freewheel hub might also be open to that criticism, also.

Scott M. said...

Any chance of building up those new dyno hubs with 26" wheels?

Le Cagot said...

Those slotted spoke holes were used on the legendary Maxi-Car touring hubs. Maxi-Cars were used on the most expensive constructeur bikes, until they became too expensive to produce. I've never heard of spoke breakage being an issue with them.

Anonymous said...

The FW hubs look very nice. Here's my vote for 120 mm hub! But I fear that I might be in the minority here...

Anonymous said...

My understanding is that dynamo hubs vary in efficiency because they are desinged to hit certain voltages at specific rotation rates. This is why, for example, Schmidt makes two hub sizes.

Another, maybe oft-overlooked aspect of dynamo hubs is how well they perform when the light is off, which to my (non-engineering) mind seems like the more difficult design challenge.

Personally, I have been sticking to my cheap (found/free) Schwinn bottle dynamo, because Midwestern drivers have interesting notions about road salt. I have heard of Shimano dynohubs seizing up halfway through a St. Paul winter, and I'm not (yet) convinced the price of a Schmidt is worth it (it's the salt, not the water, I haven't heard of good Shimano dynohubs failing anywhere else). If Chris can guarantee the seals on this upcoming hub, then I'm all over it.

Justin said...

I'll leave the slotted versus non-slotted to VO and other experts, but I will say that I'll be ordering at least one set in 126mm spacing when available. Great news for those of us who restore vintage lugged frames!

Can't wait for the dyno hub and the Grand Cru crank as well!

wycx said...

Nice hubs. Is there any demand out there for a hub with zerk grease fittings?

I might just be weird, but I would like grease fittings on all my bearings (hubs, BB, headset).

Dustin said...

Wow, these look fantastic! Any chance at all for a 40-hole version for the rear hub -- slots and all?

Keep up the good work!

Alexandra the Great said...

I'd be willing to test the new dynamo hub for you guys... I guess. Lots of salt here in SLC would challenge those seals.

On a serious note, while I imagine a randonneur might appreciate a lower rolling resistance over a LONG ride, I have never noticed my Schmidt adding too much to my task of riding home from work. It does seem, however, that getting more "electricity" out of the negligible resistance I am currently overcoming could be valuable, especially with all of the accessory charging devices coming out.

I guess if you're going to make a smoother, cheaper, pretty hub, who am I to complain :-)

Andrew Mc said...

The ornamental hole drilling of these hubs is out of line with original Maxi-car hubs. The Ornamental holes drilled on Maxi-car hubs were spaced evenly between spoke holes. This makes sense in keeping stress raisers all equal. On these hubs there seems to be no relation between ornamental holes and spoke holes. In some spots both holes seem to come dangerously close to one another! Could this lead to poorly distributed tension resulting in higher stressed areas of the hub flange?

Nate Knutson said...

I'm *really* dubious on the slots. Spoke breakage due to fatigue is a bad wheelbuilder's problem, spoke breakage due to chain drop is a racer's or bad mechanic's problem, and spoke breakage due to sticks, impacts, and more general violence is not the domain of a geared freewheel hub. If the slots come at zero compromise in terms of the design, then sure, why not, but I don't see how anything else is worth it.

Jammy said...

The quick release looks nice, but does it make any noise or rattle about when riding on rough surfaces?

I'm not sure I'm a fan of the slotted holes, just depends on if it compromises strength.

Anonymous said...

@ Anon 12:55

All the problems you see in this hub design seem to fall in the "probably" realm. You got anything a bit more, uh, concrete to back up your claims? Thanks.

tony said...

The new hubs look great. I also like the quick release end as well. Any change of seeing the latch?

Without a doubt, I would immediately purchase a rear track hub with a quick release (similar to the Suzue hub used on the Rivendell Quickbeam bikes). Of course, a hub like this should only be threaded for single speed freewheels. I'm not sure how much demand would be available for a hub like this, but I wouldn't hesitate to buy a couple of them.

You guys should lace those hubs up to some Diagonale rims and post up pictures.....they look freakin' awesome.

Preston said...

Andrew Mc's comment about the large
holes being drilled out too close
to some of the spoke holes sent me
checking my old Campagnolo Tipo hubs
which I have been using since 1976
with no problem, but they also have
the large holes very close to the spoke holes.
Regarding another comment about
the inferiority of rims and spokes in
previous times, it is true that the
first spokes made of stainless steel
were inferior and broke easily,
but otherwise my memory of 62 years
cycling does not indicate any
inferiority of spokes or rims.
Chris, what about the sharpness
on the slots on the rear hub drive
side? The do not appear to be beveled to relieve stress on the
spoke elbow.
Preston

Chris Kulczycki said...

The spoke holes/slots are beveled. Both we and the factory are looking at durability and strength issues with them. I have identical slots on the Maxi Car hubs on my own rando bike, so I'm not worried.

RoadieRyan said...

Like the QR on the freewheel hub, look forward to your upcoming hub releases.

RoadieRyan said...

Like the QR on the freewheel hub, look forward to your upcoming hub releases.

Anonymous said...

Like the new quick release style very much. I have an old Sugino QR with a similar looking nut. Is the latch equally as handsome?

Dale said...

The hubs and the QR look very cool..I'm very interested in the cassette version and would buy the QR as soon as available (and a VO 48/34 crank :-)

robatsu said...

I think with the flats on the QR tension nut, you could skip the D ring. Without the D ring, it looks a lot like the tension nut on my Mavic 501 hubs, which both looks nice and works well.

If you do insist on keeping the D ring, make sure that it is a nice friction fit and not loose and rattling around. This is a minor nit I had with a set of the Electra Ticino high flange hubs I recently purchased.

Given the performance I've had with modern spokes in well constructed wheels, the freewheel side spoke holes may be an unnecessary addition. My opinion is that they should be kept if they cause essentially zero compromise in any other aspect of the hub.

Stejdor said...

Like the hubs but my vote would be for regular spoke holes not the slotted ones. I haven't broken a spoke since the late 70's.

Tman said...

I've built up an SA Dynohub with slotted holes for the spokes. I was using Sapim double-butted spokes, but couldn't get them to sit right in the holes, no matter what I tried. The elbows of modern spokes aren't really meant to sit in those holes...

Justin said...

Will these new hubs be offered in a pre-built 126mm laced to Diagonale and/or PBP/Raid rims?

Red said...

I love the design, it's very chic. However, I'm not keen on the slotted spoke holes. Nice idea, but it just doesn't... LOOK right, I guess. I do like the QR though. If you folks get these into production, a pair may just make it's way onto my Rando project, laced to some CR-18's.

Liam said...

Please give us a 120mm o.l.d. version. Some of us are still out there running 5 speed, and looking for more options that just phil.

Jim G said...

I would love a flip/flop hub in 126-130mm with a quick release!

Anonymous said...

Chris,

Any thoughts of marrying the Helicomatic multi-shallow-pitch-thread concept to a slotted, large-flange hub?

I'm what you call a big fella, I go six foot four and two hundred forty pounds in my sock feet. I've never noticed large-flange hubs giving a too-harsh ride, for example; my size just overpowers it. On the other hand, I have noticed, spokes breaking on me through the course of a Minnesota winter (One day Minneapolis will bring its street repair to the same standards set in Beirut and Tirana).

The old lugged steel Bike Boom Bike tends to be the weapon of choice in the TC Area. Long horizontal dropouts and fenders are a difficult match; but full-coverage metal fenders are a grace from the Lord. (Conundrum!) To be able to swap out a spoke WITHOUT having to pull the wheel out of the dropouts, pull the freewheel, replace the spoke, and re-center the wheel in the fender-- Oh my, wouldn't that be nice?

What's the maximum cog size to be able to take advantage of the slots? Anything less than 26 teeth is going to be for the dilettantes. You'd be amazed at how often winter riders use a very low rear cog in the snow.

Any further thoughts on re-introducing a VO version of the MAFAC wheel guides?

john said...

My comment about the slotted spoke holes is that while is does facilitate changing spokes on the rive side without freewheel removal, what is the probability of this? Other than the small market of overloaded tourists who venture far afield and need those spokes stored on the mount on the drive side chain stay...
It to me has the look of utility, but not a real need for its design.

Anonymous said...

From a purely personal-aesthetic viewpoint, I think the design would look a lot better if there were regularity between the large flange holes and the spoke holes. Right now-- on the slotted and non-slotted sides, front and back--it looks like there is no correspondence between these two sets of holes. sometimes they are close together, sometimes not. But maybe this is just what happens when you put a ring of 9 big holes inside a ring of 16 small ones. Maybe 8 and 16 would look more regular? My observation is purely my taste, I can't say anything about the structural consequences of what looks like "just missed overlaps" between the holes. Stresses work in strange ways, and what looks visually weak might be just fine structurally.

Gabe said...

Agreed about the funkaly spaced holes. While it probably won't make for a weak flange, They'd look much, much better if they were spaced right.

The Maxi-Car:
http://www.blackbirdsf.org/maxicar/images/singer_nivex_rear.jpg

Very nice, eh!?

Kyle said...

I like the idea of 120mm freewheel hub. I can't find those anywhere. A quality one anyway. The quick release on it looks awesome. I would preorder a pair.

Anonymous said...

I like the fact that we will have a new hubset available using modern materials to replicate the capabilities of the venerable MaxiCar hubs. I would prefer to see 8 vs 9 holes of a slightly smaller dia evenly spaced between spoke holes. The "D" ring on the skewer is a nice touch. I hope the hubs will be available in a 36 hole version.

noah bers said...

I'll throw my vote in for 120mm hub. I have no plans to give up my 27" wheels or the 120mm spacing of my 1973 Nishiki Road Compe any time soon.

campagnolo4me said...

Nice hubs! I would also like to see a classic looking cassette hub. Campy 8,9 maybe? Since Campy only makes a ugly Record Hub set.

yakym said...

While I love the high flange design, it seems to me there are more than a few companies already doing formula-esque high flange hubsets.

What I would love too see, and I am sure there must be others, is a hubset with vintage campy curves. There is an elegance that the formalas just cannot touch.

Also, the QRs are nice, but if we're playing the wishlist game - would it be possible to have constructeur style butterfly closures, at least on one side?

Obviously this would be difficult to do, but I am sure there is nobody out there doing a butterfly QR :)

yakym said...

Here's an image of the butterfly closures I mentioned earlier:
http://www.flickr.com/photos/ratrocket/3956923682/in/set-72157622335870141/

Anonymous said...

Thumb down on the slots.

Anonymous said...

Desperate for a 120mm OLD that can accommodate a 5 speed freewheel for my vintage build. If you build it, I will buy it. There are none available out there...

Anonymous said...

Wow, there are a lot of people who just don't get the concept of spoke slots, aren't there? Okay guys, they're not for looks and they're not there just to enrage you... they exist for long-distance touring. When you're in the middle of nowhere and just happen to break a drive-side spoke on a normal hub, how are you going to replace it without pulling the freewheel (or cassette, if you want to be pointless)? It's either spoke slots, hiring a support van, or destroying a rim while you try to find a bike shop.

Jansen said...

Hey Chris,

Any update on the production of these?

Grey said...

I would definitely be interested in a 120 mm rear hub, and the corresponding era measurement front hub. If I could get a dynohub for my restoration that would be fantastic!

(Don't know if that comment when through. I would buy a 120 OLD rear hub today if you had them, for my 1971 Dawes Galaxy restoration.)

Thanks.