service Union bottom bracket generator?

Does anyone know if I can service my old Union bottom bracket generator?
This is a 20 year old unit, just getting back to being in active use the
past 2 years. Its pretty gritty and rough rolling, but I hesitate to open it
up or drop in any oil, knowing there's the electrical parts in there.

Any suggestions (aside from getting that cool Son front hub dynamo)?

Jack Murphy

On Tue, 12 Oct 2004 10:55:00 -0500, "Jack Murphy" wrote in
message q7Tad.4148$6P5.1807@okepread02:

This is a 20 year old unit, just getting back to being in active use the
past 2 years. Its pretty gritty and rough rolling, but I hesitate to open it
up or drop in any oil, knowing there's the electrical parts in there.

To be brutally honest I wouldn't bother. Modern bottle dynamos knock
the Union into a cocked hat, and hub dynamos are better still. You
are right: the SON is cool. Really exceptional. But the Shimano
Nexus is almost as good and comes with a nifty light-sensitive switch.

If your need is for low maintenance, low drag and no slippage in wet
weather, a hub is an obviously winner. Otherwise get the Dynosys
Litespin or the B&M Dymotec S12 12V unit.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington University

[I'm copying to r.b.tech - seems appropriate.]

Jack Murphy wrote:
Does anyone know if I can service my old Union bottom bracket generator?
This is a 20 year old unit, just getting back to being in active use the
past 2 years. Its pretty gritty and rough rolling, but I hesitate to open it
up or drop in any oil, knowing there's the electrical parts in there.

Any suggestions (aside from getting that cool Son front hub dynamo)?

Jack Murphy

I've taken apart some old generators out of curiosity. Some can be
disassembled only with a hacksaw, but some are pretty easy. Since I
don't own a Union bottom bracket generator, I don't know about it
specifically.

I had no trouble taking apart Soubitez bottom bracket generators. There
was no a problem with "electrical parts." All I found was a rotating
multi-pole magnet, and a stationary set of electical coils. There
weren't even brushes; because of AC output and stationary coils, there's
no need for them. I assume the Union is the same.

BTW, disassembling a Sturmey-Archer Dynohub will ruin the magnet unless
done exactly right, with the proper sort of "keeper," but that doesn't
seem to be true of more modern generators with more modern magnet
materials. At least, I know the Soubitez I disassembled is generating
just fine.

As Guy says in another post, there are better generators available than
your Union. But still, you've got nothing to lose by trying. I did
take pains to sketch how the fiddly bits came out, so I could get them
back in the same way. I'm talking about things like bearing races,
adjustable cones, lock nuts, etc. But all in all, it was no harder than
taking apart a rear hub.



--
Frank Krygowski [To reply, remove rodent and vegetable dot com.
Substitute cc dot ysu dot
edu]

Well, I'm much more inclined to open this unit to see if I can get some
grease in there without damage rather than spend the bucks on a hub.

I have an old sanyo bb generator on my good road bike, this is my ugly
commuter. I run fenders so really like the bottom bracket design, wish there
was a good new design in this area. With a bysis (bisys?) headlamp the sanyo
puts out good light, this commuter has an older headlamp that scatters it a
bit too much. But I also run a 10 w rechargeable, together its all the light
I need, as well as giving me the redundancy and multi-source light (hate
having batteries wear down in the cold 3 miles from home!)

Thanks for the advice.

Jack Murphy

In article p%1bd.4189$6P5.435@okepread02, Jack Murphy wrote:
Well, I'm much more inclined to open this unit to see if I can get some
grease in there without damage rather than spend the bucks on a hub.

Much as I like the SON, Shimano's Nexus is nearly as good and about 1/3
the price.
--
David Damerell Distortion Field!