Hub dynamo maintenance

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Quoted message said:

I remember dire warnings of magnetic catastrophe if fiddly things
weren't done to old Sturmey-Archer dynahubs ?

I remember that too, something about if the keeper was removed the
magnetism would be lost, sounded like bollocks to me then but I never
dared to try it.

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Hbunnet : (replace "nospam" with "athome" to reply)
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Quoted message said:

Can the team please tell me if there is anything special I need to know
before I attempt to look at the bearings on my Shimano hub dynamo ?

I remember dire warnings of magnetic catastrophe if fiddly things
weren't done to old Sturmey-Archer dynahubs ?

Is Shimano idiot proof ?

Tim

remove the lh bearing
unscrew the dynamounit (large vise, rh thread, do not crush the connector)
unscrew the connector (2 17mm conespanners and a soldering iron)

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Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Hbunnet said:

I remember that too, something about if the keeper was removed the
magnetism would be lost, sounded like bollocks to me then but I never
dared to try it.

Sheldon's dynohub page quotes the 1956 Sturmey-Archer manual :

Unless it is essential to do so, the armature and magnet should never
be separated. If they are to be separated, a keeper ring is absolutely
necessary, because the magnet will lose some of its magnetism unless
there is always iron inside it. Even a moment's separation will cause
loss of magnetism, and a spanner placed across the magnet is useless as
a substitute for a keeper ring.

BEWARE !!

Tim

Thanks Marten.

Does this mean that I need a soldering iron to inspect/regrease the
right hand bearing ?.......

Tim

Quoted message said:

Thanks Marten.

Does this mean that I need a soldering iron to inspect/regrease the
right hand bearing ?.......

Tim

yes, also note the position of the various washers while you're at it

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Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl