In Order to Form a More Perfect …Beast?

Today’s post is brought to you in three sections:

I.  Today is Constitution Day in the United States.

Our Constitution begins in its preamble “We the people of the United States, in order to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this Constitution for the United States of America.”

Over its next three section—Articles I, II, and III—the Constitution lays out, in surprisingly few words, the legislative, executive, and judicial powers, respectively, of the federal government. Article IV sets out the relationship of the federal government and the states. Article V (thinking ahead) sets out the process for amending the Constitution. Article VI, very brief, insures that the Constitution does mean repudiation of prior debts owed by the United States—indeed, it assumes the existence of the Nation, and declares the Constitution “the supreme law of the land.” Finally, Article VII sets out the requirements to ratify the new document.

The main text of the Constitution is followed by a series of amendments, the first ten of which form what we call “The Bill of Rights,” protecting what we like to think of as the fundamental freedoms.

Interestingly, though, the Bill of Rights is followed by an additional 17 amendments, the content of which ranges from matters as trivial (from an early 21st-Century viewpoint) the enactment and repeal of Prohibition (Amendments XVIII and XXI, respectively) to the abolition of slavery and the expansion of the rights of younger citizens (XIII, XIX, and XXVI).

These latter amendments are just as fundamental as the first ten. Some are about fundamental rights, and some are about fundamental duties.

Read your Constitution. Whether you love it or not, know it. It’s a remarkably short document. After 250 years, with all amendments, it runs to 21 pages in PDF format (in comparison, the new Iraqi constitution runs to more than 40 pages).

That’s about all I have to say about that.

II.  Following up on yesterday’s post…

Yes, I’m feeling better today. I worked on the bike and I rode it in this morning. I’m sitting in Bruegger’s right now, watching the morning creeping up Dixwell. It’s going to be a good day.

III.  And the Beast.

Almost two years ago, I wrote what has been a rather popular post here. In case anyone’s interested, I’d like to report an upgrade to that project.

Regular readers (hi there, you two!) know that I have a bag fetish. That is, I want the right bag for the job. This, sadly, turns out to extend to bicycling as well—though here I have a little more room for modifications.

Over the past two years, my Garneau-based beast has worked well. I’ve played with others, notably the Velo Orange Campagne bag and the Ironweed Orpington. Whie I liked both, for different reasons, each was not quite right for what I wanted. The VO was too small; the Ironweed, too enormous. The VO had hardware that rusted a bit, and tended to jingle; the Ironweed had the right hardware, but its pockets interfered with cables on my bike. The Orpington opened away from the rider with a buckle; the Campagne opened toward the rider but with a hard-to-use bit of elastic.

My original beast was good, but the map case was difficult to use, and while it opened toward the rider, it closed with a “watertight” zipper, the plastic seal on which was deteriorating. Finally, I realized that what it had in common with the Orpington was that it came too close to my fingers on the brakes (I like a narrow handlebar—between 40 and 42 cm).

So, back into the search. Someone on a message board happened to mention that they knew of a Japanese company that handled getting domestic products to international buyers. I browsed the site, and noticed that they handled Ostrich bags, which I had previously seen on Velo Orange’s site and in a few other places. They had seemed a little on the large side, but I thought I’d look just for the heck of it to see if Ostrich made a smaller bag.

Enter the F516.


At about $50, plus shipping from Japan, this one is made of nylon rather than canvas (it comes in black or gray, and there is a slightly more expensive canvas version as well). It’s taller than my original beast, but has no side or rear pockets. It has one front pocket that closes with a Velcro flap that covers almost the entire front, and a small zipper pocket on the front of the flap (good for small things you don’t often need). Then it has a very nice large map pocket on top and—ta da!—closes at the back with Velcro.

It was made to, and comes with straps to, fasten it to the handlebars and a rack. I removed these and performed a variant on the original beast’s attachment.

So far, it’s pretty good.


It’s narrow enough that my hands don’t feel squoze when I’m using the brakes. It’s large enough for lots of spare clothing, plus a small U-lock and cable. Reflectors are always nice. I dunno. I like it. Check back in a couple of years for a long-term evaluation.

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Feeling Flat

This morning, I drove my Alleged Car to work for the second day in a row. O, joy.

The explanation is complicated and unsatisfactory.


Saturday Morning, ready to depart

On Saturday, I did my usual second weekend ride up to Woodbridge to open the Family History Center, but I stuck around after the FHC closed because I was supposed to go with another member to assess some left-over damage from Hurricane Sandy later in the afternoon. So I sat, read, wrote, the usual stuff.

Around 4:00, I was picked up and we went out to Milford to inspect the situation—on a house with pilings that should have 6’ of clearance, it was down to about 2’, so that’s something we’ll need to organized. The sky was flat and gray, and it started to rain fairly hard while we were out there, but I figured I’d survive.

When I got back to the FHC where I’d left my bike (indoors) I changed into rain gear I had brought in my panniers and headed North and East, toward Hamden.

Generally, I find riding in the rain to be peaceful and happy. Roads feel smoother, the spray from under my fenders looks cool, and as long as I’m warm (the weather was cool as well as wet, so I was wearing a wool cycling sweater and “normal” shorts under rain pants and rain jacket) , it can be very Zen. So I rode north on Racebrook Road, East on Ansonia and Fountain and down under I15 into Westville. I have eyes that are sensitive to cold wet winds, so I also wore a set of these from Portland Design Works, but even so the rain was heavy enough to kind of harsh my vibe. Any time you have to wipe your lenses (in spite of a helmet visor) it’s raining a little too hard.

So there I was on Fitch when I started to notice a little bounce and roll in the rear wheel. A quick check at a stoplight verified my suspicion; the rear tire was going flat.

I shouldn’t complain—this was my first puncture since The Accident.  Heck, I had begun to suspect that my pump was getting lonely!

Fortunately, it was not going flat too quickly. A couple of times I pulled off to the side of the road and grabbed my frame pump to bring up the pressure, but that wasn’t a tenable situation given that (a) I’m heavy and (b) that I had lots of stuff with me in panniers and other bags. Fortunately, being on Fitch, I was not far from the school where I adjunct (Southern Connecticut State University), I had a place to go. Though I didn’t have m office keys with me, I suspected my building’s vestibule would be open. In fact, it was, and I was able to get into the lobby, where a couch proved useful:


Really useful furniture, SCSU

I figured it was a small leak, and so it proved. A little hard to find, but once I located a pit in my rear tire, it was easy to verify by pulling out the tube at that spot and pumping the tire up. A nice cool stream of air. So I dug in my underseat bag, and then in my handlebar bag, for a flat kit. And then I remembered that the last place I’d seen it was on my dresser. At home.

Fortunately, I had two tubes with me—one each in the underseat and handlebar bags. I decided to use the one from the front bag, even though I remembered it as vaguely suspect for some reason. I checked for any remaining foreign object, found none, put in the tube and pumped. Soon all was well, I reloaded the Rando, and rode carefully across campus back to Fitch, stopping a couple of times to pump in more air. (As much as I like frame pumps, it’s hard to tell when you’re at the right pressure.)

I made my way back to the bike trail, and made it home without further drama. I wiped down the chain, which looks a little dirty but runs quiet (thanks to Chain-L), and the sidewalls (different rag) and went and had a long hot shower.

Next day was church, and a service project, so I didn’t get a chance to go down to the Bike Cave. Instead I helped clean out a hoarder’s apartment (imagine filling an industrial-sized dumpster with, well, everything—including multiple computers covered in cat shit, a dead cat, lots of TVs and CRTs, open cans of food, etc. In fact, we ran out of room and needed another dumpster. It was the warmest day we’d had in a while, but I wore nitrile gloves and a mask, duct-taped my jeans legs closed (based on expert advice about potential fleas), and threw away my clothes and shoes when I got home.

I took another shower—a long, long shower—and watched an episode of Manhattan on Hulu, and went to bed.

When I woke up, I went down to the Bike Cave only to find that the suspect tube was getting soft. Since I had slept late, I didn’t have time to change it, and since I knew the battery in the AC was charged, I drove all of three miles to work, and then the five to SCSCI. Blech. I think I taught a good class, but I didn’t feel jazzed the way I think I should have.

Today, I got up feeling depleted, and decided to drive again. I’ll repair the bike properly tonight.

I don’t know which came first, depression or not riding. But I feel the same kind of gray as the sky of Saturday afternoon.

Sometimes it just feels like too many things are happening, sometimes like I’m stuck in place. I do think it’s missing the bike; the hoarding situation on Sunday depressed me, and I didn’t have the bike to revive me. And that lead to the cycle of driving, not fixing, and driving again.

So tonight, I’ll put my hands to good use and bring that bike back into proper order. And tomorrow I’ll ride it to work, and I’ll ride it to SCSU, I’ll take my chances locking it up in New Haven (albeit with a good lock and rack in a relatively safe part of the city). And I suspect that with the rear tire less flat, my feelings will be as well.

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When I was a kid, I used to read MAD Magazine.  I loved the MAD fold-ins, Dave Berg’s “The Lighter Side of…” and of course, Spy vs. Spy.  But one of my favorite things was the stuff that appeared not in, but around the comics.  These “Marginal Thinking” bits were the work of Sergio Aragonés, a true master.

This post is not about Aragonés, but about his opposite.  And it is about margins.

The massive posts I’ve been doing here under the general heading “The Shocking Truth” were fun to write, and it was a blast to experiment with different types of generators.  But the biggest lesson I took away from doing them was that there wasn’t all that much of a difference insofar as the functionality of the generators was concerned.

Which is to say that the differences I did find were, for the most part, marginal.

It’s worth emphasizing that much of life is like this.  We (particularly we in the “first world”) have it so good that we find ourselves fighting it out over differences that are pretty minor.  They matter only at the edge.  For cyclists, this means that a bike frame that weighs grams less than another is significantly more desirable.  Music enthusiasts strive for the lowest possible THD, even when the difference is inaudible.

We pay a lot for small differences.

Aragonés’ marginalia made a huge difference.  In some ways, it was what made MAD what it was.  But the difference between an old bottom bracket dynamo and a hub dynamo or a Velogical unit is pretty damned small for most people.

I guess what I’m trying to say, after all of the reviews are over and  the smoke has cleared, is that it doesn’t make sense to buy “THE BEST ” unless only that will do.  If you can make due with a little less, if you don’t fall into one of the marginal cases?  Save your money, or, better still, give it to a food pantry near where you live.

That will make a far larger difference.

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The Shocking Truth, Part 8: Penultimately Speaking

I say penultimately because everything is provisional. Lights are improving, and I expect dynamos/generators to improve as well.  It’s getting better all the time!

But life is all about tradeoffs. Having eliminated (for most purposes) the bugaboo of generators slipping in the rain (by “rain” I mean what most of us are willing to ride in, not monsoon conditions), we are left with the following items:

· Power

· Weight

· Noise/Vibration

· Subjective resistance

· Aesthetics

· Cost

Now, to rate each of the dynamos on these factors. I will give each a “+” if it did subjectively better (my subjectivity) in a given category; a “0” if was middle of the road, and a “-“ if its performance was sub-par. Then I’ll give a very quick set of comments for each unit.

Hub Dynamo:

Power Weight Noise/ Vibration Subjective Resistance Aesthetics Cost
+ - + + 0 -

If you want to feel like you’re riding on top of a laser, nothing beats a hub dynamo. You have instant-on lights and plenty of juice. But they’re heavy and costly: they add significant weight to a bike, and you’re going to have to have a new wheel built. Many feel that the oversized front hubs required are ugly—I don’t think so, but they’re not especially pretty, either. On the other hand, there is practically no noise or vibration when you are using these hubs, lights off or on. Before I started on this project, I would have said that even when the lights are on, the resistance is undetectable. I’m much less certain of that now. It’s only a few watts with the lights on, and very little indeed with them off, but yes, I think I can feel the difference (with the lights on).

For me, these tradeoffs are worth it. Simply to know that I can be seen at the flick of a switch isa reassuring, and the weight doesn’t bother me. For anyone who rides in all weather conditions and needs their lights to absolutely work in spite of what Mother Nature puts out, the dynohub remains top choice.

Bottle Dynamo:

Power Weight Noise/ Vibration Subjective Resistance Aesthetics Cost
0 0 - - 0 +

As an inexpensive, inexhaustible source of power, the bottle is hard to beat, which may explain its survival in multiple forms after many years of battery domination. It puts out adequate power for the 3W StVZO standard, and while it may be more noisy than some of the alternatives, it wins on a cost basis. Beware of paying too little, however, as some bottles are more cheaply constructed than others. The look is utilitarian, but the unit is clearly an add-on, something that might tempt thoughtlessly destructive people to make it a wrench-off.

Traditionally, these dynamos mounted to the rear wheel. Had I been able to do that with my frame, I might have found the idea more appealing. As it was, I found a front-mounted bottle to be noisy, though redirecting it to the rim (rather than the sidewall) reduced this issue. This can be done with dynamos equipped with rubber rollers; those with metallic rollers present an additional risk to lightweight sidewalls.

Bottom Bracket Dynamo:

Power Weight Noise/ Vibration Subjective Resistance Aesthetics Cost
0 0 0 - + 0

The worst thing about the bottom bracket unit is that it is no longer being produced. While its power and weight are on a par with that of the bottle, its location low on the bike helps reduce noise and vibration, and while it produces some resistance from rubbing on the tire tread, it is practically invisible. If I wanted to light a classic bike, and the classic aesthetic didn’t include something like a Soubitez bottle, this would among my top choices.

While the bottom bracket unit benefits from its location, it can be comparatively difficult to find (due to its arguable obsolescence). But this should not remove it from your consideration. My first dynamo was a bottom bracket model, and it was a revelation to finally have light whenever and for as long as I wanted it. If you’re up against financially, you may find one of these for cheap—certainly, cost-wise it is at least on a part with a decent bottle.

Velogical Rim Dynamo (Trekking Model):

Power Weight Noise/ Vibration Subjective Resistance Aesthetics Cost
- + + + + -

The Velogical is amazing; although it is only rated at the 1.5W StVZO standard, it is capable of supplying lights and a USB charger at the same time. It weighs—well, it weighs very little, runs smoothly on the rim (thanks to the O-ring) and feels like it adds very little in the way of load to the bike. It’s attractive while being compact enough not to look like an add-on (many will look at a bike and simply miss the Velogical altogether if they’re not looking for a rim dynamo). It’s unlikely to be a target for vandalism or theft.

Its primary weaknesses are its comparatively low power output, its cost (which may price it out of the range of commuters, but which should be understood as not requiring a special wheel), and its very-low-speed performance. As to the last, Velogical Engineering, after reviewing my review, suggested that the dynamo could be reversed on its mount (something I should have thought of, but didn’t). Since the wire handle on which the dynamo is mounted passes through its base to one side of the center of rotation, reversing the dynamo on the wire (easily accomplished with a grub screw) allows you to increase pressure and so improve low-speed performance—something I did not account for in my review. Here’s a photo that illustrates this improved position:


Note that the dynamo has been reversed, so that the wires come out at the far side. Note also the use of a thicker O-ring and the very clever way in which the wires are passed through some of the extra holes in the mount—which should prevent the kind of damage I was worried about. Overall, these modifications should deal with some of my concerns with this unit.



Dynamo Power Weight Noise/ Vibration Subjective Resistance Aesthetics Cost
Hub: + - + + 0 -
Bottle: 0 0 - - 0 +
B. Bracket 0 0 0 - + 0
Velogical - + + + + -

OK. So, time for some recommendations. If it’s absolute power you want, and you’re willing to pay the price (which is not inconsiderable) nothing is going to beat the hub dynamo. Riders who spend a lot of time out in the dark, in bad weather, who need their lights, really need look no further. But if weight is a concern, you need not look here. Fortunately, for most of the riders in the categories I’ve described, weight will not a deterrent—their bikes are already loaded for bear. But for some randonneurs, weight and daytime resistance may militate against the hub.

Typical commuters would be well served by either the bottle or bottom bracket model. In fact, the bottom bracket unit is likely more survivable, in spite of its location in the nastier elements of the road. It’s less likely to attract attention, and it can run on the tread of smooth-ish tires. Therein likes the rub; tires with external treat (i.e., MTB tires) will not work with the bottom bracket model. For such uses, the bottle is superior, especially if it can be run on the rim rather than the tire sidewall. The cost is low, but the price to be paid comes in noise and vibration (and likely because of that noise and vibration, a heightened sense of resistance—though by no means of the Bart Simpson level). Nevertheless, both the bottle and the bottom bracket dynamos promise power unlimited by battery life—and both can be completely removed from the resistance equation when not needed. These are the daily commuter’s tools of choice.

Finally, if weight is at all an issue, and if cost is not, the Velogical promises phenomenal cosmic power (OK, perhaps not quite in magnitude, but certainly in duration) in an itty-bitty living space (I do miss Robin Williams). If you race and occasionally find yourself out after dark; if you are a randonneur of the minimalist, high-speed, carbon frame school; if you simply want an excellent source of light without needing to dedicate a wheelset to that cause, the Velogical is your dynamo of choice. With modern LED lighting, its lower output power does not present a serious problem, and only its cost may serve to keep it out of the hands of more riders.

A Closing Note

I have enjoyed tremendously the opportunity to test these various units. If you’re interested in learning more about dynamo lighting systems, let me recommend typing some of the terms used in the evaluations I’ve done (both this article and early Shocking Truths) into your favorite search engine. There are decades of experience out there, and much (though by no means all) of the past 20 years is preserved on the net.

I encourage readers to add comments to this site, particularly at the end of this post, linking to other articles, disputing my findings, correcting my mistakes, offering to send money ;-), etc. I am a cyclist. I ride (occasionally) in spandex and (often) wearing a Styrofoam hat. I have no dignity!

Herewith, I conclude my major—though probably not last, you poor souls—writing project on dynamo lights. I’ll be seeing you, well lit, on the road!

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The Shocking Truth, Part 7: Something Old is New Again: The Velogical Rim Dynamo

EDIT 8/29 8:15 AM  Edited to clarify the position of the dynamo in the second photograph.

(quick edit–I forgot to properly title this Shocking Truth installment when I posted it.  That’s the only change).


When I decided to do this series, I initially planned to look only at the three most common types of dynamos. Then, in the course of looking into bottle dynamos, I encountered rumors of a wondrous new device—the rim dynamo from Velogical Engineering that was supposed to weigh virtually nothing and cause very little resistance, while matching modern hub dynamos in output. I looked around for a US Source, and could not find one, so I contacted Velogical by email and described the sort of project I had in mind. A person with Velogical responded and asked some questions about my blog, and the sort of thing I wrote, etc. I asked Velogical whether they would be willing to lend me a unit to evaluate, and they responded by giving me my choice of units (they make three) and mounts (there are several), and told me that I could keep the unit “if I liked it.”

To the extent that this influences the review, you should be aware that I paid for each of the other units considered here, and so—from a social-psychological perspective—I think that the influences cancel each other out. While I might favor Velogical because of their niceness in giving me a unit to evaluate, I might also favor one or more of the units in which I had invested (“sunk costs”). You should decide for yourself the validity of my review here, but you should be aware that there is difference in the source of the units, and that it may have affected my review, one way or the other.

So…tell me about the Velogical?

Velogical makes three units: a SPORT model, “for minimal ride resistance and maximum speed.” A TREKKING model “low ride resistance and reserves of power when riding more slowly, for double headlight set-ups or city riding speeds.” Finally, a SPECIAL model for “Maximum power supply even at low speeds, for special applications, for example special chargers for on-board electronics or double headlight set-ups.” These differ externally primarily in terms of the color of the top cap of the dynamo—red, silver, or blue, respectively.

I elected to try the TREKKING (hereafter, Trekking) unit because it seemed like a reasonable compromise, and because I’m slowing down in my old age J. And I chose a left-side, rear mount version—for much the same reason that I had done with the Dymotec 6: I wanted to keep the dynamo out of the way (fortunately, as discussed below, I did not run into the same mounting issue).

Velogical shipped the unit quickly, and so I came home one day to find a small box waiting for me. Initially, it felt empty. I opened it up to find the dynamo, already attached to its mount, a selection of required small hardware, multiple O-rings, and a thermistor (a small Halogen bulb) to be used in series with the dynamo and the light system (See the Wiki entry here).

My first reaction on seeing the dynamo was that it was jewel-like. Here’s a photo showing it next my eDelux headlamp:


The eDelux is a pretty small headlight, in my experience. Now look at the Velogical: remember that it’s only the upper half that’s actually a power generator; the disk-shaped section that the wires pass through (below the knots) is the interface to the mount. You can see the silver top cap and the barrel. Between these is the O-ring that actually makes contact with the rim.

I really want to like the Velogical unit. But while it is tiny and elegant, there are some issues, particularly at low speeds. With the dynohub (and to a lesser extent with the other dynamos) rolling my bike from its resting place at my workbench to the basement hatch produced flashes of light from both front and rear lights. With the Velogical unit, nada, save for—after a little while—a dim glow from my Pixeo taillight. To my mind, this is indicative of suboptimal performance at very low speeds. Granted, most people are not going to ride at those speeds.

Of course, once you’re moving at any decent speed, lighting performance is satisfactory.

There is a comparatively little noise from the Velogical unit to start with, and it gets absorbed quickly into wind and traffic sounds, a little faster than with the other units. The sound is soft and hum-like, probably due to the (in my opinion) superior wheel-roller interface. The comparatively large roller means that the roller turns fewer times for a given rotation of the wheel than the Dymotec 6, and the smooth, grippy surface of the O-rings is makes less noise. Pressure on the rim is supplied by a wire bale spring arrangement. The position of the dynamo relative to the mount can be adjusted using a grub screw in the dynamo body. The arrangement allows for three positions: Engaged, disengaged (which backs the dyno .5 cm or so away from the rim), and “loose,” which allows for the removal of wheels with tires that significantly overhang the rim. This is a useful feature to have if you have fat tires. However, the wire spring arrangement means that the only way to adjust tension is to move the dynamo body closer to the rim—and that affects the resting position of the dynamo as well. So a highly-tensioned dynamo will also have very little clearance when not in use. Here’s a view of the mounted dynamo:


EDIT 8/29 8:15 AM:  Velogical asked me to clarify this photo a little.  Note the write handle at the right of the mount is in the middle position.  In this position, the dynamo is disengaged from the rim.  Moving the wire handle out at the bottom (so that it rests against the outer pin at the lower right of the mount) tensions it against the rim; moving it in the other direction (past the inner pin at the right of the mount) detensions it completely, so that rims with overhanging tires can be easily removed, or the O-ring on the top of the dynamo replaced.  The dynamo is shown in its “stowed” position, with the wire handle between the two pins–this is where you’d normally have it during daylight hours.

As you can see from this photo, the mount is a simple block of aluminum, held by a U-bracket. You can see the wire spring on the right end, resting in the middle position. The mount has multiple holes, to allow adjustments in positioning, and comes with two U-bolts, so that you can handle both thick and thin stays. Different mounts are available for different bike types and locations. Because I use caliper brakes and have no cantilever studs or dynamo mount on my frame, I chose and was sent a left-rear mount.

Hint: You will need a 6mm nut driver to install this mount. Different tools may be appropriate for different mounts. Once you have it set up where you want it, you tighten the 6mm nuts on the ends of the U-bolt to hold everything in place, then loosen the grub screw on the bottom of the dynamo body to adjust position and tension.

Unlike the Dymotec and most other bottles, almost the entire outer surface of the dynamo (the shiny cylinder) rotates. It turns with an ease that suggests good bearings.

One electrical consideration–unlike the Shimano and Sanyo units, the Velogical is not grounded through its body and mount, so you must run connections from BOTH wires to your lighting system.

Once you’ve done that, simply flip the wire spring to engage the dynamo, and you’re good to go. I

OK. How does the Velogical rim dynamo, Trekking model, stack up?

Costs Associated with Velogical Dynamos


As far as I know, there’s only one source from which to obtain the Velogical units if you live in the United States, and that’s Velogical Engineering itself ( I am told that Velogical is building relationships with US sources, but I was unable to find any through a search before I contacted Velogical.


Unfortunately, the Velogical dynamo does not come cheap. The unit price, including one mounting bracket and Value Added Tax, but excluding shipping, comes to 150 Euros, which today is about $200. Additional mounting brackets are priced at 30 Euros, VAT included. In my experience with purchasing from Europe, VAT is generally rescinded from orders sent to the United States, but it isn’t clear to me just what proportion of the 150 Euros is VAT. (VAT is a little complicated if you’re not used to it.) I believe that VAT on the Velogical would be about 19%, so the unit price is around $160 on the back of an envelope. That’s significantly more than a hub dynamo, but remember that you can use your existing rims and do not have to have a new wheel built.


Velogical claims a weight of 75g for their dynamo, and while I expect this excludes the (very small and light) bracket, it’s still pretty remarkable. It’s about half the weight of one of Shimano’s latest Dura Ace “direct mount” brakes—which, I suspect, makes it a worthy in the weight-weenie book. It’s certainly the lightest unit I tested by a significant margin.***



Installation, described above, is a little less complicated than with a conventional bottle dynamo, though not as simple as a bottom bracket unit. You place a sticky foam pad on the mount, which goes on the inside of the chainstay. You then place one of the included U-bolts around the stay and through some appropriate holes in the mount. The U-bolts (which come in two lengths to account for differently sized stays) are covered with plastic, probably heat-shrink tubing, to prevent damage to your bike’s finish. Once you have the U-bolt through the mount, you place a small washer and nut on each of its legs, align the dynamo so that it runs straight on the rim (alignment with this unit is just as important as it is with the conventional bottle), and tighten the two nuts against the mount.

You will want to have a 6mm nut driver for this operation, because you are going to need to work through the spokes of the rear wheel to adjust and tighten the mount. That’s probably not a scarce tool in Europe, but Velogical might consider including a small nutdriver for their US sales. If you have a good ratchet set, it probably has a 6mm socket (yay! Craftsman) and you can use that. I also kind of wish that Velogical had supplied nylock nuts. These have become my go-to fastener, and while you can surely do without them, they provide a little extra security. Velogical does supply a tiny Allen wrench to help with fine adjustments of grub screws.

I should note that my particular installation is probably a lot more complicated than some; if you have canti-type mounts, the Velogical unit can be purchased with a simplified mount that attaches to a stud. That makes front-mounting much more practical (and that would have other advantages—see below).

Finally, I should also note that one of the advantages of size is that, even with its position near the rear rim, the Velogical unit fits entirely within the triangle formed by the seat stays and the axle (only the very outermost edge of the U-bolt is outside that triangle, and only by a tiny margin). This means that I did not encounter the problem I ran into with the Dymotec of accidentally “kicking” the dynamo with every pedal stroke. Small size has its advantages.


The Velogical unit does not ground to its mount (and hence does not ground to the frame) unless you choose to make that connection yourself, so you will need to run a two-wire connection to your lighting system.

Interestingly, the Velogical dynamo eschews the kind of tiny lugs we’re used to seeing on European lighting equipment—instead, the dynamo comes with two long pigtail wires that extend from the bottom of the dynamo. These are securely tied off in the lower (mounting) section, so they can’t be yanked from the dynamo by accident.

Velogical favors connection to the dynamo through heat-shrink protected twisted-wire connections. That is, you take one of the dynamo’s two wires, strip some of the insulation, take a wire from your headlight, strip of the insulation, place a bit of heat-shrink tubing (Velogical supplies this with the kit) over one of the wires, then twist (“braid”) the two wires together securely. Slide the heat-shrink tubing over the connection, and heat it with a soldering iron, heat gun, or hair drier. The heat-shrink tubing conforms to the twisted shape of the connection, not only insulating it but making it more mechanically secure. Note that this is easier to do with simple wire connections than with coaxial wire—if your light (like the eDelux) uses coaxial wire, you may find this a little frustrating at first, but it’s worth the effort. The resulting connection is electrically and mechanically solid.

One more thing worth mentioning here. To greatly simplify—as voltage rises for a given resistance, current also rises. This can lead to a dramatic increase in the power going into a given load (what was, once upon a time, before the advent of Zener diodes, responsible for headlight bulbs “blowing” on descents). It can also harm the generator. To protect against this problem at high speeds, Velogical supplies a thermistor—in the form of a 15w halogen bulb. The bulb has very low resistance (c. 1 Ω) when cold, but that resistance increases as the bulb heats. This helps to reduce the power curve at very high speeds, protecting the dynamo and the electrical system. The way it is used, it is unlikely that the bulb will ever give off any significant amount of light.

It is the user’s responsibility to wire the thermistor—which is supplied with long wire leads—in series between the dynamo and the electrical system. The trick here is that Velogical does not give you a place to put the thermistor. Since it can sit anywhere between the dynamo and the rest of your circuit, it might make sense to place it on the headlight mount. But it seems to me that Velogical would have done better to supply a clip for the thermistor as part of the dynamo mount. Perhaps a bulb that fits into a socket could be used, and a socket built into the mount.


Overall Performance

I found the Velogical rim dynamo to be satisfactory as a power source, but not overwhelming. In fact, Velogical was in the process of getting StVZO certification at the time I received my dynamo, and it’s worth noting that the approval they did receive—while I was in the process of evaluating the dynamo—was for a device that generated not 3W, but 1.5W. This classification is possible because the “new generation” of lights, which are all LED-based, need less power to generate adequate light (Note also that Shimano produces less-expensive hub dynamos that also fall into this lower power range).

But just because the Velogical is certified at 1.5W does not mean that it can only generate that level of power: as we shall see below, it is capable of powering lights at the same time it can charge a USB device. But it does imply that the Velogical is not likely to generate the same surplus of power that a device certified at 3W does. In practice, I noticed this in the way my lighting system, which was designed for a 3W or greater generator, responded.

Generally, I found the eDeluxe and Pixeo combination to be a little less bright when I was using the Velogical than when I ran them with other dynamos when running at low speeds (10 MPH and under). There was also a decrease in the time that the headlight took to switch to its lower-brightness standlight mode, and the standlight circuits did not seem to continue to keep the head- and taillights going for as long after a stop. All of these nice “extras” depend on the generator putting out extra energy that can be stored, e.g., in a capacitor, to keep things going when the bike stops.

Wet Performance

Slipping in wet weather is a bugaboo for all dynamos outside of the hub units. But like the Dymotec and bottom bracket units I checked, the Velogical did not appear to slip. In fact, I had the opportunity to try it in a fairly drenching rain, and it kept the lights going—though as noted above, perhaps not as brightly at the lower “rain” speeds as the other units—even while I was getting thoroughly soaked. This is pretty impressive given the relatively weak spring force holding the unit in place.

Charging performance

Because of my experience at low speeds, and because I consequently tended to think of the Velogical unit as a “weak” generator, I was not expecting the rim dynamo to be up to the task of charging an additional device. Happily, I was wrong. Although it took a moment while I rolled out of the driveway and built speed, I was very pleasantly surprised to hear my phone chime to let me know that it was charging. Because I do not have adequate tools or time, I cannot tell you if the phone was getting a significantly lower charge than it would from other devices (indeed, I cannot rank the devices in this respect) but there should be at least enough power to keep a small USB device running, if not charging.


With the rear mount, you really need to dismount to switch the Velogical dynamo into working position. It’s likely that such would not be the case if it was mounted on a cantilever post, but I found the bale impossible to work from my riding position.


Position helps, but the Velogical is pretty quiet from the get-go. The sound that it does make is lower-pitched than that of either the Dymotec 6 or the Sanyo bottom bracket units, more of a hum than a whine. It was by no means unpleasant, which was a nice change from the (front-mounted) Dymotec’s siren song.


There is a slight but detectable vibration from the unit when you’re walking the bike with it in its engaged position. Once you’re actually riding, however, the vibration disappears, and all that’s left is the hum noted above, and that vanishes into the wind at around 12 MPH.

Subjective Resistance

Does the dynamo cause resistance, and can you feel it?

The first answer is, as always yes

The second is more complicated. Once I had the Velogical mounted, my sense of its resistance was surprisingly low, so I decided to do a quick spin-down test. First, I connected my lights to the hub dynamo and spun the front wheel, hard. With the lights connected, the front wheel stopped spinning fairly rapidly. Next, I connected the lights to the Velogical, engaged it, and gave the rear wheel a similar spin. It took significantly longer for the rear wheel to come to rest, with the rim dynamo engaged, than it had the dynohubbed front wheel.

Consequently, while you can feel the resistance of the Velogical, it gives the impression of putting a very small load on the wheel compared to the other units I tried. I should also mention here that since the Velogical runs on the rim rather than the tire, like the bottom bracket dynamo, it frees you from concerns about sidewall wear. And since the physical load is quite low, any concern about rim wear should also be relieved.

What explains the surprisingly low physical resistance of the Velogical? Several factors probably contribute, and the first is simply that it is not built to put out as much power as older units. My guess—and it is only that—is that for a given load, the Velogical will achieve 3W of power at a higher speed than the other units looked at here. Moreover, I suspect that all three of the other dynamos I tried will exceed the Velogical’s output at any reasonable given speed.

But, as I said, that’s only part of the story. The Velogical dynamo, being as small as it is, certainly must have a different arrangement of magnets and coils. It is likely that, as relatively low-priced, mass-produced units, development on sidewall dynamos remained relatively (pardon the pun) static for a long time. Velogical’s 21st-century foray into dynamos takes place against a backdrop of computer simulation and computer-aided design and the development of more powerful magnets. It’s simply a better mousetrap.

Finally, the same factors—price and mass production—that limited updated design of the sidewall dynamo also affect its construction. The Velogical costs four times as much as the Dymotec, and it shows. As noted above, the unit turns easily, in a way that suggests good bearings and precise construction.



While the dynamo itself is sealed, Velogical makes available a range of mounts, and the dynamo comes with several O-rings, allowing for replacement of the roller surface. Simply roll the old O-ring off the top of the unit, and roll a new one on. The literature that comes with the dynamo describes the supplied O-rings as being made of a special compound, but I suspect that a visit to your local hardware would supply at least a temporary replacement should you run out of replacements. Of greater concern in the US is the possibility of losing a few fasteners from the mount, since tiny metric U-bolts and nuts are scarce, even around bike shops. However, if you do things right, this should not be an issue (and is almost certainly not an issue for the cantilever stud mount).


I don’t have a sense of the overall strength of the Velogical dynamo. If I have any concern, it’s with the wire spring in the mount. I’m sure it’s quite strong, but over time, it may wear—and it certainly could get hooked on clothing and bent. But it can also be bent back into shape. Further, because you have to use the wire pigtails rather than lugs to connect to the electrical system, I could see a situation in which the wire would be damaged in such a way as to leave it too short for repair…

Attractive Nuisance?

The Velogical unit is a joy to behold and, for a very perceptive and well-equipped bike thief, a potentially valuable prize. However, it is also small. It’s the sort of thing a bike enthusiast might get excited about (indeed, at least one bicycle has been built around the Velogical unit!) but not something likely to make for a quick grab. It probably won’t be noticed.

So, what’s not to like?

When I first started writing this review, my early drafts all started out “I really want to like the Velogical unit.” I still do. I think it’s an excellent bit of engineering and it works very well. That being said, I am, as an American, all about power. The Velogical is sufficient as a power source, but it does not pile on the power the way older units, or hub dynamos, do. As a daily commuter, I find that the lower output of the Velogical makes me a little nervous. Not a lot. My nervousness comes about likely because I’ve used a hub dynamo for years and that has formed my expectations.

The lower output of the Velogical may come about in large part because all of the earlier units were designed to work with incandescent lights. The Velogical rim dynamo is designed specifically for a 21st-century technology: LEDs. Consequently, it does not need to pump out the kind of juice that you need to keep a filament hot. Instead, it takes advantage of the efficiency of LEDs to permit a smaller, lighter, smoother power source.

This comes at a cost, however: lights and generators are engaged in a kind of dance: the generators we have now—other than the Velogical—are designed for less efficient lights; the LED lights that have emerged in recent years reflect (sorry, pun) the power output of those generators. They take advantage of the extra juice. If the dance continues, we may see more dynamos shrink (I referred to the lower-power Shimano hub units above) as LED technology improves.

All of this comes together in the Velogical’s comparatively lack-luster performance at very low speeds. If I had to pull directly into low-speed traffic when leaving my job, I would be concerned for at least the first few seconds (10-15) that my lights were not working at optimum brightness, and that the standlight circuits were not adequately charged. That concern would be easily alleviated by a little stretch of parking lot or other pavement that allowed me to bring the bike up to speed and the lights up to charge. Not a big concern, but it’s there.


My next blog will draw this whole thing to a close, with a comparison of the four dynamos and some suggestions as to what kind(s) of users will benefit from each. It may be a few days in coming, but it is coming.

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Sorry for the Delay!

I want to take a moment to apologize for the delay in posting the Velogical review.  I took on a few too many things this past month, and lawschoolissoover has suffered as a result.  It’s nearly complete at this point, and I just have to look at a few more things.

It will be posted before the end of the week–hopefully by Wednesday evening.

Again, my apologies.

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Do Not Need , Do Not Want (a law school is so over joint)

A brief break from The Shocking Truth…

You’d hardly think it to look at me or my lifestyle, but I am genuinely trying to cut back on crap (seeCrap).

One of the ways I’ve decided to do this is to try to limit my “impulse” purchases, which tend to make up the bulk of my expenditures.  This is easier to do with in-person than with on-line purchases, for reasons that I will discuss briefly below. 

These days, I try only to be in a store when I need something.  That’s not rare–I may need a particular kind of bolt for a project I’m working on, for example, or a plastic box, or a tie (though gods know I have enough of those!).  When I’m in a store, all kinds of things present themselves.  Ideas emerge.

So I’ve started to think hard in terms of needing things.  And if I cannot find a present need for the object in my hand, I tell  myself that I do not want it.

Does it work?  Well, yeah.  If it’s something I can hold in my hand, I can do a pretty good evaluation.  Do I need it now?  Do I even have a place to put it, whatever it is?  If I do not need, the only justification for buying is because I want, and I have decided (in advance) not to want. 

It’s a lot harder with online purchases because they lack both the tactile feel of things and because the transaction itself is bloodless.  I don’t need to even hand over a card.  Heck, I can do “one click” ordering on Amazon.

I suppose one of the reasons I’m doing The Shocking Truth review is to somehow justify in my mind the money I’ve spent on various dynamos. 

Sad, really.

But I’m getting better.  Honest.  You’d be amazed at what I didn’t buy this week.

We now return you to your regularly-scheduled blargh..

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