Bicycle Mechanics - Experiences with Sanyo Dynamo Hubs?

I'd love to hear any experiences folks have had with Sanyo Dynamo hubs. They seem to be cheap and weigh about the same as the mid level Shimano hubs... just wondering if the light output is crappy or if there is a lot of drag or anything?

I already have a Shimano LX generator hub and recently had a bike with a Shimano DH-3N80 hub stolen (LAME!). I'm not looking for advice on these hubs or on Son hubs (which are wildly out of my price range at the moment). I know those are far superior hubs, but I'm just looking into cheap options for replacing what was stolen.

Thanks!

I'm gonna answer myself here, in case anyone else is interested in the topic. I build up a front wheel with said Sanyo Dyno hub and it works great. I don't notice extra drag and it powers the generator light just as steadily as much more expensive hubs, though it is a little heavier. It only cost like $35 on ebay and is a great budget alternative.

I'd love to hear any experiences folks have had with Sanyo Dynamo hubs. They seem to be cheap and weigh about the same as the mid level Shimano hubs... just wondering if the light output is crappy or if there is a lot of drag or anything?

I already have a Shimano LX generator hub and recently had a bike with a Shimano DH-3N80 hub stolen (LAME!). I'm not looking for advice on these hubs or on Son hubs (which are wildly out of my price range at the moment). I know those are far superior hubs, but I'm just looking into cheap options for replacing what was stolen.

Thanks!

No personal experience, but the Sanyo H 27 was tested in the April 2012 edition of the German Magazine "Fahrrad Zukunft". The H27 had surprisingly high drag with the lights off, especially at higher speeds. With the lights on it compared well to e.g. Shimano 3N80. The H27 has an efficiency around 60% while e.g. the SON is around 70-78% depending on speed.

The conclusion was, that the H27 did well as an economical solution for those who always have their lights turned on and didn't ride very fast most of the time.

But it was also noted, that tiny advantages or disadvantages in measurements shouldn't be the sole deciding factor: warranty, serviceability etc. should be weighed in too. So before buying the H27 ask about bearing replacements, can they actually service the hub, or is it a throw-away item when then the bearings are worn?

FYI the Shimano 3N72 is electrically identical to the Shimano 3N80 (in fact, all the Shimano "3 Watt" Sport Dynamos measures alike). It weighs a little more, but is likely stronger (steel axle, thicker flanges), and is somewhat cheaper too.

AFAIK , the dynamo component of All the Shimano hubs Could be based on a Sanyo design ..
perhaps the Sun-race Sturmey Archer ones too .. TW is a small Island..

AFAIK , the dynamo component of All the Shimano hubs Could be based on a Sanyo design ..
perhaps the Sun-race Sturmey Archer ones too .. TW is a small Island..

No they aren't. Besides the fact that the current Shimano "Sport Dynamo" design pre-dates the Sanyo H27 and that they in all likelihood are designed in Japan, not Taiwan, and Shimano dynamohubs uses cups and cone bearings while Sanyo H27 is a cartridge bearing design, they all measure quite different, eg. the H27 has twice the parasitic drag of the Shimano 3N80. The SR-SA's hub I have seen measured aren't even in the same league as the H27 when it comes drag, output and efficiency.

Sanyo the Corp. is a post WWII company, while the British SA made dynohubs in the 1930's. Old SA dynohubs have some internal resemblance to Shimano dynamo hubs but differs in several ways.

A hub dynamo is simple thing to design, so all designs tends to look alike with a stator and a rotor and some wire encased in a hub shell. Shimano would of course have examined old SA dynohubs when they started producing their own, but they certainly didn't copy them, probably they learned more from the faults of the SA hub than from its fundamental design.

So been there and looked?

NB SA was sold off years ago, now they're on Taiwan too..

so no comparisons to 30's UK really apply..

So been there and looked?

Not sure what you mean, but I have actually seen many disassembled dynamo hubs, and I have serviced and repaired my own Shimano 2N70 and 3N71 dynamo hubs. The "Trinity bicycle" guide to overhauling Shimano dynamo hubs have several photos of the internal structure of Shimano dynamo hubs, while detailed SA Dynohub exploded diagrams can be found many places on the net, so you can see for yourself.




NB SA was sold off years ago, now they're on Taiwan too..

Shimano and Sanyo are both Japanese companies, they may do some manufacturing in Taiwan or Malaysia, but AFAIK their R&D is (was) done in Japan. According Wikipedia, none of Shimano's three main plants are even in Taiwan. I am not aware that Sanyo had any bicycle related manufacturing done in Taiwan either. (Sanyo doesn't exist any more except as a brand on certain products).




so no comparisons to 30's UK really apply..

I think it does, since the original British SA pioneered dynohubs a decade before Sanyo even existed, the British SA design is much more likely to be the influential one. When Sanyo started to produce dynohubs they must have been looking at SA hubs for inspiration, not the other way around. I also think that the present SR-SA design is much newer than the present Shimano hub design.


All in all I think it is safe to assume that neither Shimano nor SR-SA have based their dynamo hub internal designs on some unspecified Sanyo design, besides the fact that they have internal different structures(1), like bearing designs, and that they measure quite differently. That this Sanyo design should have spread to the different companies via Taiwan doesn't seem likely either, since SR-SA seems to be the only Taiwan based company.

(1) The current SR-SA dynohub internal design does resemble the present Shimano design in some ways, especially the connector system, but are AFAIK, newer than the current Shimano design, so SR-SA copied Shimano, not the other way around.

I have 2 bikes with dyno hubs. One has a Shimano 3N72 and the other has a recent SA with drum brakes. The test bench may be able to measure drag but in real life I cannot notice any difference in drag for either of them, on or off. Nor can I tell any difference if I mount a non dyno wheel. If you are concerned about performance I would say that there are many other variables with more significant affect: tire pressure, road surface, wind, weight.

-G

I built a wheel with one of these hubs recently. I know it has a lot of drag in theory, but in practice I don't notice it. I can't speak to reliability over the long term yet, but it strikes me as a very good value for the price so far.