Shimano Alfine DH-S701 1.5v Dynamo

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BrianP
Posts: 194
Joined: 14 Apr 2011, 9:12am

Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by BrianP »

interestedcp wrote:
BrianP wrote:Reading around this site and others the SP-PD8 looks very well regarded and probably my best bet in terms of quality, performance and value. Would you experienced guys agree.


I don't agree with that. I think the main problem is that it can't serviced (like replacing it bearings), unless the entire wheel is taken apart. After the two year warranty expires, you will have to mail the hub directly to the factory in Taiwan in order to replace bearings. If you don't build your wheels yourself, this may add significant cost, since you have to pay for both taking the wheel apart and be assembled again.

Its performance is very similar to the the 3W Shimano Sport dynamo, yet it is much more expensive. It is lighter however, since it uses a aluminum axle instead of steel etc.

The bearing quality on the Shimano dynamo hubs is vastly superior in both shielding and quality to the SP hubs.

BrianP wrote:Light to go with it looks like this one http://www.starbike.com/en/supernova-e3 ... oCyYnw_wcB

Which seems a very good price for such a product. Might be because light is on all the time, no switch!

Just need a USB connecting bit for this solution. Any offers?



Haven't seen the beam pattern from this Supernova light, but generally speaking, the B&M lights have superior beam patterns because they also use indirect reflectors.
The 80 lux "Lumotec IQ Cyo Premium senso plus" is likely to be a better performer at half the price.
http://www.bike-discount.de/en/buy/lumo ... /wg_id-303

The Luxos U is almost the same price, but comes with inbuilt USB charger.
http://www.bike-discount.de/en/buy/lumo ... /wg_id-303

Regarding USB chargers; the idea is seemingly so simple, but there are several factors that are worth considering: Will the setup work when it is raining? Can you both charge and have usefull light on? Battery buffers may help some devices that don't like fluctuating power, but if the load on the battery is larger than the input, it will run dry, and probably refuse to charge until they have reached a certain capacity again. Some devices may not be usable while charging, or at least require changes in the setup to do so.
Last, there is the quality of the charger: some have surprising high parasitic drag, even when off. Some don't deal very well with high speed descents, some aren't weather proof, etc.

The best charger on the market in terms of electrical measurements, is the B&M E-Werk. Some figures can be seen here (in German though): http://fahrradzukunft.de/12/steckdose-unterwegs-2/

Presumably the B&M USB-Werk is of the same quality. It is simpler and probably what most people need since most devices will be USB these days. It has an inbuilt buffer battery with all the advantages and disadvantages that brings.


Do the comments about Shimano Sports hubs having better bearings etc apply to the Alfine 3w hub which is just £50 from SJS
http://www.sjscycles.co.uk/shimano-alfi ... prod30900/

Cheapest SP-PD8 is almost double that and the point about taking the wheel apart and sending off to Taiwan is a real negative. Are any of the Shimano hubs serviceable bearing wise?

An XT version is only a little more expensive http://www.bike-discount.de/en/buy/hub- ... Ag168P8HAQ

Just to put into context, I am waiting for delivery of a 29+ Singular Rooster frameset and the rims which are velocity Dually 29 x 45mm have just arrived into the UK so need to decide on hub charger soon. This bike will be an off road tourer so will the lower speeds mean I should choose a certain dynamo which works better at these reduce speeds. Need 32hole disc for 700c/29er in black.

Brian
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honesty
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Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by honesty »

WOOLIFERKINS wrote:The USB plug has gone from the current version of the Luxos and been replaced with the properly waterproof adaptor the ewerk uses so the only weather dubious connection is from cable to device.


As the USB connector is part of the handlebar mounted switch this is not as much of a problem as it may seem. The switch is held onto the handlebar using one of those industrial elastic bands that garmin use. When it rained I just unclipped it and stuck the whole switch into my barbag and carried on charging happily. I could still see the status of the light and control it from the switch on the back of the light as well, so no big deal really!
Brucey
Posts: 44521
Joined: 4 Jan 2012, 6:25pm

Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by Brucey »

BrianP wrote:
Do the comments about Shimano Sports hubs having better bearings etc apply to the Alfine 3w hub which is just £50 from SJS
http://www.sjscycles.co.uk/shimano-alfi ... prod30900/



yes, if you look at the EV techdoc for this hub you can see that nearly all the parts of this hub are identical to those used in the DH-3D72 model. It is basically the same thing in a slightly different frock. a good buy IMHO.

Cheapest SP-PD8 is almost double that and the point about taking the wheel apart and sending off to Taiwan is a real negative. Are any of the Shimano hubs serviceable bearing wise?


they all are if you know what you are doing, including the RH bearing.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
BrianP
Posts: 194
Joined: 14 Apr 2011, 9:12am

Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by BrianP »

Are there any technical reasons why the XT hub would be better for off road use rather than the Alfine, or are the internals the same? You sort of expect the XT version to be tougher and better suited to wet and mud?

Brian
SA_SA_SA
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Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by SA_SA_SA »

Are these much cheaper than 3W ones?

Are they easily available?

Are any other manufacturers going to make 1.5w Hubs?
------------You may not use this post in Cycle or other magazine ------ 8)
Brucey
Posts: 44521
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Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by Brucey »

BrianP wrote:Are there any technical reasons why the XT hub would be better for off road use rather than the Alfine, or are the internals the same? You sort of expect the XT version to be tougher and better suited to wet and mud?

Brian


dh-t785 is basically a dh-3d80 with different branding; all the parts interchange. Vs the dh-3d72 model, the dh-3d80 has a larger diameter axle made of aluminium not steel, and larger cones to go with it. The design of the seals is similar in principle. I do not expect there to be a very great difference in the performance of these hubs in real-world use.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
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interestedcp
Posts: 380
Joined: 5 Jan 2012, 3:34pm

Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by interestedcp »

BrianP wrote:
Cheapest SP-PD8 is almost double that and the point about taking the wheel apart and sending off to Taiwan is a real negative. Are any of the Shimano hubs serviceable bearing wise?

An XT version is only a little more expensive http://www.bike-discount.de/en/buy/hub- ... Ag168P8HAQ

Just to put into context, I am waiting for delivery of a 29+ Singular Rooster frameset and the rims which are velocity Dually 29 x 45mm have just arrived into the UK so need to decide on hub charger soon. This bike will be an off road tourer so will the lower speeds mean I should choose a certain dynamo which works better at these reduce speeds. Need 32hole disc for 700c/29er in black.


Just to put things in context: Some dynamo hubs like the SP8, or the SON Edelux are made by two shells pressed together. That means the wheel has to be taken apart in order to get to the cartridge bearings inside. The SON therefore uses expensive SKF bearings, combined with a "breather" system that helps keeping moisture out of the bearings.

The Shimano 3W "Sport" hubs are basically identical in electrical output and drag. You pay for features like disc brake and weight savings. They are all cup-and-cone bearings, and the bearing races are extremely polished/grounded (Borazon) just like their Ultegra road hubs. Their sealing is AFAIK double lipped labyrinth seals, which, as long as their is grease enough to lubricate the seals, are considered the best practical hub sealing arrangement.
This makes for a hub that probably can go on for many years without any service.

The "official" way of servicing them, is simply to use them until the bearings are destroyed, and then change the entire internal assembly. In short, you change everything but the hub shell and the magnets inside it. This cost approximate as much as a new hub. The advantage is that it is a really simple operation; if you can adjust a cup-and-cone bearing, you can do it. It also takes reasonable short time to do, and is something that can be planned ahead, so there is very little "downtime" where the wheel can be used.

A second way of servicing them is to take the hub apart. This isn't officially supported, since there is a tinned copper wire running through a slot in the axle, that breaks easily if handled wrong. That means it requires some knowledge to take the internal assembly apart to reach one of the bearings. There are instructions on the net on how to do it.

The third way is probably the easiest and best method. I haven't tried it myself yet, but Brucey on this forum have pioneered the method; You basically just loosen the cones enough to squeeze in some grease.
Haven taken several Shimano dynamo hubs apart over the years this seems to be a very good solution: In all my hubs the grease was clearly disappearing, by eg. migrating into the hub or bleeding outwards. As long as there is grease enough inside the labyrinth seals seems very effective in keeping dirt and water out, and the bearings and cones are so well made that they look practically new even after several years of winter riding.

All in all, I think one can expected a very long lifespan on the Shimano 3W Sport hubs if the grease is replenished at intervals by the "Brucey" method.
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interestedcp
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Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by interestedcp »

SA_SA_SA wrote:Are these much cheaper than 3W ones?

Are they easily available?

Are any other manufacturers going to make 1.5w Hubs?



They don't seem to be much cheaper in retail. Clearly, Shimano aren't trying to pushing the 1.5W concept on price. It looks like the target demographic are "urban" commuters that want something that looks sleeker and is lighter than the usual 3W hub dynamo hubs. They are probably more meant for bike manufacturers than retail.

They ought to have lower resistance too, but the only Shimano 1.5W model I have seen tested did fairly badly in that regard. Anyway, the resistance from Shimano's 3W dynamos is so low that nothing practically is gained from lowering the output to 1.5W.

At least for the moment, all the several hub dynamo dealers I know of have a 1.5W model or two.

Not sure if any other manufacturer follows up on the concept, perhaps Sram will. Of course, if the concept is a runaway success, more will follow, but I doubt it.

The 1.5W dynamo hub concept is fine enough in principle; many urban commuters doesn't need more since modern LEDs are so effective. For more all round use including dark country roads, and especially when it is raining, I think the 3 Watt models makes much more sense.
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peterh11
Posts: 290
Joined: 20 Mar 2010, 10:25pm

Re: Shimano Alfine DH-S701 1.5v Dynamo

Post by peterh11 »

interestedcp wrote:
SA_SA_SA wrote:Are these much cheaper than 3W ones?

Are they easily available?

Are any other manufacturers going to make 1.5w Hubs?



They don't seem to be much cheaper in retail. Clearly, Shimano aren't trying to pushing the 1.5W concept on price. It looks like the target demographic are "urban" commuters that want something that looks sleeker and is lighter than the usual 3W hub dynamo hubs. They are probably more meant for bike manufacturers than retail.

They ought to have lower resistance too, but the only Shimano 1.5W model I have seen tested did fairly badly in that regard. Anyway, the resistance from Shimano's 3W dynamos is so low that nothing practically is gained from lowering the output to 1.5W.

At least for the moment, all the several hub dynamo dealers I know of have a 1.5W model or two.

Not sure if any other manufacturer follows up on the concept, perhaps Sram will. Of course, if the concept is a runaway success, more will follow, but I doubt it.

The 1.5W dynamo hub concept is fine enough in principle; many urban commuters doesn't need more since modern LEDs are so effective. For more all round use including dark country roads, and especially when it is raining, I think the 3 Watt models makes much more sense.


The rolling resistance from current 3W dynamo hubs is so low that I see little point in a 1.5w hub for most people, especially as there is a lot more choice of lights for 3W dynamos. I have been running a Shimano DH 3N30 for about 5 years now on my commuter (heavyish hybrid with Nexus 7 gears and 622-37 tyres), and I have never been conscious of extra drag. Aktiv Radfahren magazine in Germany just published a new test on dynohubs by the way. If there is interest I can look out for it on their web site (they seem to put articles on there a little while after publishing the original report so it is not there yet) or put a translated summary on here. None of them have lights-off resistance above 2W.

The B&M lights are a lot cheaper from German sites like bike-discount, by the way. One tip, if fitting a decent LED headlight, get a security bolt to replace the standard Allen key bolt if you plan to leave it around town a lot. Someone stole my wife's Cyo earlier this year - clearly knew what they were doing as they carefully unplugged the cable and unwound it from the frame, before unbolting the light and taking the lot,including the dynamo connector which I had to replace separately.

Peter H
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