Does anyone have a picture or rear B&M Dynamo mounted on Dynamohalter fixture or anything else?



A

A Muzi

Guest
Günther Schwarz wrote:
> [email protected] wrote:
>
>> On Feb 20, 4:23 pm, Günther Schwarz <[email protected]> wrote:

>
>>> <http://www.xn--gnther-schwarz-gsb.de/Pictures/ice10.jpg>

>
>> Regarding that setup: IIRC, the Lightspin generator shown pivots into
>> contact with the tire by tipping inward, not swinging as a door
>> swings. That is, the axis of rotation for engaging the generator is
>> perpendicular to the axis of rotation of the generator's drive wheel.

>
> Yes, it works exactly like that.
>
>> Many other generators swing in like a door swings, the pivot axis
>> being parallel to the main rotation axis. Those types are better NOT
>> mounted as in Gunther's example, with the pivot ahead of the
>> generator.
>>
>> The reason is, both freedom from slipping and generator drag are
>> greatly influenced by contact pressure of the drive wheel. If a "door
>> swing" generator were mounted as shown, the generator's resistance
>> would make it dig harder into the tire, causing more drag and more
>> tire wear.

>
> Such a trailing arrangement in front of a fork leg or seatstay may
> actually also offer a small advantage in case a bolt comes loose.
>
>> This is why many generators come in "left" or "right" models.

>
> I don't know of any that is not offered in two chiral versions: Left for
> mounting in front of the left fork leg and right for the right one.
> Also the Lightspin and the Nordlicht as the two most prominent examples
> of the vertically tilting variant come in both versions. The one
> pictured in my posting is a left model.
>
>> With the Lightspin shown (or any other one that pivots as it does)
>> it's not a problem.

>
> Actually I would prefer to mount it differently as it interferes with
> panniers. But the rear triangle is too small to allow for a trailing
> position and if mounted below the left chainstay it would be exposed to
> a lot of grid and moisture.


Brazed fork mounts are nice.
And dynamos should always use Nylock mounting nuts on the bolts. A
dynamo dropped into a wheel is an ugly mess.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
 
D

ddog

Guest
I think found an appropriate pair of lights for the mean time as an
alternative suplemented with my current visual light:

http://ecom1.planetbike.com/3002.html

One or two - 3.5W lights for up to $50 is not bad and already have
recharger. 4 to 8 AA nice rechargable batteries will bump the price up
too.
 
N

Nigel Cliffe

Guest
ddog wrote:
> On Feb 21, 6:44 pm, "Nigel Cliffe" <[email protected]> wrote:
>> Peter White has the better 3N70 hub for $90. I'm using one on my
>> (well cared for) touring bike as the best compromise product.
>> Significantly cheaper than the Schmidt hub, and almost as good.



> But the wheels won't be CR18 rims and DT db spokes. I've heard Shimano
> Mavic wheels have a designed max cap around 180 lbs rider. That may be
> good for Japan and Europe, but I've got 60 more lbs.


That depends who makes the wheels. Don't know in the US, but in the UK you
get standard stock wheels, and you get hand assembled ones. With hand
assembled you get whatever rims/spokes you want. (I expect Peter White can
get hand assembled)

I can't give you a report on the Shimano hub for a heavy rider; I'm only
150lbs. However, it does go over unmade tracks and roads, and I'd be
confident if it was loaned to a heavy rider.

But, I can assure you that a Schmidt hub will take the weight, I know of
three heavy Schmidt users:
One who must weigh around 240lbs solo. He's had it for years and it doesn't
break or go out of true. He's also had his bike wheels for years, and once
he discovered that decent hand made wheel builders can do a good job his
wheels no longer break.
Two tandems (different pairs of riders). Combined weight of pairs must be
280lbs. Again, years of use, long distances and some modest rough track
use.


If its weight, talk to a wheelbuilder about appropriately strong wheels.

- Nigel


--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/
 
D

ddog

Guest
Nigel,

I went ahead and got Planet Bike 3.6W for down road peripheral vision
and use my bright 1W for immediate track vision. $37 total including
ship with 4-Sony NiMh batteries.

But look at this thing. Longer cycle times, brighter light, and no
changing/charging AA bateries.

http://www.foxfury.com/products/pro_series/bike/bike.htm

If I routinely rode at night, this looks like the ticket. New
technology. No wonder Litespin went under.


Thanks for your help,
Phil Bailey
 
?

=?ISO-8859-1?Q?G=FCnther?= Schwarz

Guest
Andreas Oehler wrote:

> The Lightspin dynamo is out of production for some time now.


They started another production run last year. This is were I got mine
from.

> The company went bankrupt:

<http://www.moneyhouse.ch/u/lightspin_ag_in_liquidation_CH-170.3.028.221-7.htm>

Ups, so it might be time to look for the last ones available.
I wonder what will happen to their intellectual property. While not
directly applicable for hub dynamos their unique alternator principle
might be useful for small windmills or high efficiency motors.

Günther
 
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=?ISO-8859-1?Q?G=FCnther?= Schwarz

Guest
A Muzi wrote:

> Günther Schwarz wrote:
>> [email protected] wrote:
>>
>>> On Feb 20, 4:23 pm, Günther Schwarz <[email protected]> wrote:

>>
>>>> <http://www.xn--gnther-schwarz-gsb.de/Pictures/ice10.jpg>


>>> With the Lightspin shown (or any other one that pivots as it does)
>>> it's not a problem.

>>
>> Actually I would prefer to mount it differently as it interferes with
>> panniers. But the rear triangle is too small to allow for a trailing
>> position and if mounted below the left chainstay it would be exposed
>> to a lot of grid and moisture.

>
> Brazed fork mounts are nice.


These were simply not possible for that trike. The most elegant solution
that I'm aware of is a pair of bosses similar to the ones for water
bottle cages as offered as an option by Patria:
<http://www.patria.net/bikes/08_trondheim/bilder/trondheim_600px.jpg>
(Not a very detailed picture, but one can see the alloy holder that is
bolted to the inside of the left seatstay)

> And dynamos should always use Nylock mounting nuts on the bolts.


Yes, of course.

> A dynamo dropped into a wheel is an ugly mess.


This is why I use a double clamp. Belt and braces.

Günther