What dyno hub is best for $$, based on vibration/smoothness?
 

Not sure if I asked this here, but I need to get a second dyno hub for my wife's bike. Can anybody compare the Shimano, Shutter Precision PV-8, Sanyo and SON hubs? I know from the recent Jan Heine articles that the light outputs (i.e. electrical power outputs) are very similar for the Shimano, SONs, and the Shutter Precision, but what about quietness and vibration? I get a small buzz from my 6-year old SON, but are the much cheaper Shimano and SP as smooth? Is the difference worth another $100? SP PV-8 is typically about $135 on Ebay, while the Shimano is a little less and SON is nearly twice as much (more for some models!). I got my SON in a wheel set which was underpriced; I've been reluctant to buy one new due to my inner cheapskate acting up.

I have to say shutter precisions, I have two shimanos from different years and they both vibrate.

Here's a review on dynamo vibration.

http://swhs.home.xs4all.nl/fiets/tes...agneet-sterkte

I've only noticed vibrations from my Shimano hubs at fairly high speeds. It doesn't really bother me though. I'm pretty sure it's more closely related to the lights than the hubs

I have a SON 28 and I don't notice any vibration. I looked at a lot of dynamo hubs before buying the SON. It definitely had the least resistance when spinning the wheel by hand. I don't know if you would noticed the difference riding though. The SON is expensive but for me it was worth it since my winter commute is dark going and coming home from work. The SON also has stainless steel bearing and a very good warranty. How much is she going to ride/use it? If it's only occasionally I probably wouldn't buy a SON but since I use mine for 3 hours a day everyday (in the fall/winter) I could justify it.

It won't be for daily or long commuting, and she doesn't have any plans to do brevets. This year I plan to work up to a 200k in the spring, and more long rides as the season goes on. I'll get her to accompany me on whatever she wants to manage. We've been able to do 65 mile rides together in past years. More prosaically, she might do one to several longish country rides per week combined with daily utility riding. Cross-town to the fabric store is a 12 mile round trip, as is a run down to the mall. She doesn't like to have a range of purpose-built bikes. Rather, one is enough.

I read the Dutch survey of nearly everything on the dyno lighting landscape. He likes the Shutter Precision PV-8 more than nearly anything, and has not found the perfect headlight. He does not like the Luxos B or U, nor very much the other B&Ms. He likes the Phillips Saferide 80 for faster riding and the Saferide 40 (not sure it is made for dyno power) for in-town riding. He feels that Dutch riding has stronger requirements for brightness than the German STVO standard, and perhaps that's why he dislikes the Luxos.

For Mrs. Road Fan's bike, I've already bought her a Luxos B, so my problem is simplified. I'm going to look for a Shutter Precision for her. Virtues: silver, shiny, smooth, compact, not too $$, lots of power, not much drag.

Ok, new twist on the question:

Sanyo H27 resistance with lights off?

In his latest review of dynohubs, Jan Heine recorded that the lights-off rolling resistance of the Sanyo H27 was, while normal at lower speeds, greater than any other dynohub on test at higher speeds, and was greater than the lights-on rolling resistance. As odd as this sounds, it's what he reported. If it is not a fluke result, the fast H27 users of the world should be complaining because this should stand out subjectively.

Have any H27 users noticed excessive drag, or have any fans of dynohubs (you know who you are, the ones who read every word ever printed on dynohubs) seen similar results in other reviews? Can any fellow EE geeks (like me) propose why it might be a correct result? I've been planning to order a Shutter Precision for my wife's bike, but the Sanyo is just so much cheaper it's hard to overlook. And according to Heine's review this resistance is the only deficiency in performance, and it certainly seems like a fluke to me.

So, has anyone experienced this issue, or read about others reporting this issue, or have an explanation of this behavior? If it's totally implausible, maybe Jan's data recording guy just didn't get the data correctly.

Or, I can just buy it and not put an on/off switch on my wife's bike.

I have never been able to tell that I have a dynohub on the bike. I have an incredibly cheap Shimano, a H27, and two higher-end Shimanos. I have a PD8 I've never used. If I was getting a hub for recreational riding, I definitely would get a Shimano or a Shutter Precision. Although, now that I think about it, the H27 has studded tires on it, so that probably isn't a good data point.

What vibration are you talking/worried so, about?

I have only noticed vibration from a shimano hub when using a highly tuned DIY light. Otherwise my three hubs have been smooth.

Vibrations caused by the magnetic notching between the magnets and poles. Poles are wedge shaped to help minimize this but based on a number of factors (e.g. load, resonance...) it can obtrusively perceptible at certain speeds.

I have been riding on the PV-8 for about a year now. I do get a small vibration at about 20+ mph. Does the whole front end shake and is dangerous, no. It is a very subtle vibration. My commute is about 8 miles each way. It does not affect this at all. I have used this hub to do 50+ mile rides and the vibration still does not affect me.

My wheel is the PV-8, Open Pro rim and DT rev. spokes.

Unfortunately, this is the only dynohub I have experience with. I can not compare it to anything else. I absolutely love the hub dynohub to my old battery set up.

Has anyone had a vibration so bad, it made their hands go numb or affected their ride?

Yes, exactly, Looigi! As an electrical engineer I call it "cogging," but you've given a very good explanation.

I get some of this vibration on my SON driving a Luxos B around 17 mph. I'm not sure it would bother Mrs. Road Fan, but smoother is always better.

Captsven, the vibration with my SON is nowhere near strong enough to cause numbness or affect bike control.

Znomit: You mentioned a "a highly tuned DIY light." What does this mean? High current? Very large input or stand light capacitors? or what? I could imagine higher current causing more intense cogging.

another mattress, prince(ess)?

only notice any of that magnetic pulsing, with the wheel in the truing-stand , never riding the bikes.

What I've read says that the Sanyo is noticeably less efficient (though obviously also cheaper) than the Shimano. The Shimano is technically not quite as efficient as the SON, but that difference is fairly minor.

I bought a Shimano Alfine because it seemed like the best price/performance ratio. At the time I think it was less notchy than the SON to, but I don't remember exactly.

I've got a SP PD8 on my Salsa Fargo along with Luxos U and have never experienced any vibration while riding at any speed or load. You can feel the notchyness while just spinning the wheel but once underway it is not noticeable. I've never actually felt anything through the bars. I plan on building up another SP hub for my CAAD9. It will be interesting to see if it's noticeable on the much lighter and responsive bike.

The "vibration" is a mild hum-hum-hum when the light is turned on (my diy light has a switch beside the brake lever), that only happens on my steel commuter with Shimano dynamo. It doesn't happen on my aluminium touring bike or my carbon/aluminium road bike, same dynamo.


I believe he's talking about the variants of diy light circuits made from this site. http://pilom.com/BicycleElectronics/DynamoCircuits.htm

Very very bright with 6 leds setup, brighter than anything in market, great for mountain biking or for people who don't care about road specific beam pattern.

On my Specialized E5, it's not noticeable.

I think if you are worried about vibration and drag, Son, SP, and one of the better Shimanos are your only choices. I find that it's hard to true a wheel with the low-end hubs because the drag is so high. Might not be the same at speed, but it's annoying in the truing stand.

There is a resonant system formed by the hub windings, the light electronics, and the fork and tire. I used to have a home built circuit 7 pilom light that had obvious resonance at a different speed than my Luxos or Supernova lights. It really depends on all of the elements. I don't think you are going to get away from it unless you are using a highly-damped carbon fork

I agree completely! The SP dynamo was by far the most annoying wheel I have ever built. It may have just been my cheap truing stand but it was tough to get it to spin correctly. I finally just gave up and rigged up some axle extenders for it to rotate freely.

It was a dual LED light tuned to drive the LEDs at 1A.
See here, Martin makes nice well behaved circuits but you can tune the capacitor values to give a big peak.
http://www.pilom.com/BicycleElectron...uits.htm#Boost
Think I only noticed it on smooth asphalt over a small speed range.

Oh, another one I made would vibrate… turned out my rectifier was only catching half the waves.

This is interesting. My bike is late '80's Rossin steel bike. Maybe the steel has more of a resonance characteristic. To be clear, mine is a vibration felt on the bike and not a hum sound from the hub.

Anyway, the vibration is very subtle but measureable. I still recommend this hub to anyone interested in dynohubs. The vibration is not enough not to avoid use.

Isn't the SP dynamo switchable? As in, you can mechanically disengage the dyno part when it's not in use?

--J

The comparison between hubs is interesting. I have Edelux/Son28, have always noticed the vibration, and it appears that the Edelux is the worse culprit among tested lights, though this just could be because it pulled more current than the other tested lights.

Ok, so essentially you designed it for Martin's "nice" curve, where the power curve has the same shape as a so-called "critically-damped" pulse response?

If I'm the cycling analog to "The Princess and the Pea," so be it.

But if one's insensitivity is deep enough, one has no need of a bicycle above say, a 1969 Raleigh Record, with pitted hubs. Is this you?

The 7 series is switchable. I have the 8 series.