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
> [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