dynohub repack?

Got to thinking today as I was cleaning yesterday's muck off my bike...

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) Cool!

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On 18 Okt., 22:26, Nate Nagel wrote:

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

I have really good experience with Kool Stop salmon colored brake
pads; not only does they brake very well, but they are really gentle
to the rim because they don't pick up alu pieces etc. With KS pads I
no longer need to clean the brake pads, nor do I bother with cleaning
the rims for other reasons that the rims look good when clean. Still,
I can hardly detect any wear on my rims. The downside is that KS seems
like a slightly odd company with a iffy distribution, so sometimes
there are veritable droughts of KS brake pads, at least here in
Europe.

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72)
and is there an
exploded diagram of it anywhere? I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

It is doable, but don't do it unless there is a specific cause like
rough bearings. The reason is, that one side of the bearings are so
problematic to maintain that Shimano has deemed it non-serviceable. So
when looking at the exploded Shimano diagrams, notice how only only
one side is serviceable. The problem is that the wire from inside the
rotor that generates the current, runs along in a trench in the axle.
It is very, very easy to break that wire when disassembling the rotor
part to get to the bearings.
On the upside, many people have reported +15000 km without any need
for repacking the bearings, and from what I have seen from my Shimano
generator hubs, the sealing is excellent and just riding in the rain
certainly isn't a reason to repack them.

There used to be a blog where some guy documented how to take the
rotor apart, but the site has disappeared. But here some hints;

Get a good feeling for how the wheel rotate when the cup and cones are
adjusted correct before taking it apart. The magnets makes normal cup-
and-cone feeling of preload difficult.

Measure dish on the wheel first, make sure it is centered. Take
accurate measurements of the distance between the end of the axle and
lock nuts. This is to avoid any unnecessary fiddling with the rotor
side lock nut and cone when assembling the rotor part again, since
this risks breaking the rotorwire. Place the lock nut and cone right
the first time when assembling the rotor.

Document exactly how you take the rotor apart with a digital camera.
Again the reason is that the wire seems only to be able to take that
many bendings before it brakes, so avoid too much fiddling, but
reassemble it correctly the first time.

You don't need any special tools, but a lancet and a pick will be
handy.

You take the cone off on the rotor side by screwing it off the axle,
but since the rotorwire runs along a trench /slot in the axle, the
cone may grab hold of the rotorwire and rip it apart when the taking
the cone off. So be careful that the rotorwire doesn't protrude above
the slot. Perhaps use a lancet to clean off the gum that Shimano seems
to use to glue the wire to the trench with, but avoid cutting in the
wire insulation.

There seems to be good reason to assume that the "hidden" cone inside
the rotor is identical with the other "visible" cone, so in case off
pitted cones, just order to two "visible" cones.

Be prepared that it may take longer than you thought it would, so
don't do it if you need the wheel later in the day, or early next
morning.

AFAIK, the rotor doesn't loose its magnetic power when out of the hub
shell like some old SA generator hubs did.

--
Regards

On Oct 18, 3:26*pm, Nate Nagel wrote:
Got to thinking today as I was cleaning yesterday's muck off my bike...

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? *I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! *I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) *Cool!


http://techdocs.shimano.com/media/te...9830608789.pdf

Drive side bearings serviceable. 11 loose bearings. Top up with some
thick grease and forget about it for a year.

Peter S. wrote:
On 18 Okt., 22:26, Nate Nagel wrote:

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

I have really good experience with Kool Stop salmon colored brake
pads; not only does they brake very well, but they are really gentle
to the rim because they don't pick up alu pieces etc. With KS pads I
no longer need to clean the brake pads, nor do I bother with cleaning
the rims for other reasons that the rims look good when clean. Still,
I can hardly detect any wear on my rims. The downside is that KS seems
like a slightly odd company with a iffy distribution, so sometimes
there are veritable droughts of KS brake pads, at least here in
Europe.


That's what I keep hearing. I'm going back and forth between just
getting what I have, but in salmon (I think they're called Eagle Claw II
or something, and cheap) or what I put on my other bike, which are
called "Cross Pads" (e.g. cyclocross) but really appear to be a Dura-Ace
pad holder with a cantilever mount on it rather than the usual road
brake mount. The latter are way more expensive but I've been happy with
them on the other bike, and it appears that if I got those, the pads are
short enough that I could remove the straddle wire and then just flip
the brakes open and scrub the pad surfaces with a toothbrush and some
soapy water after a particularly abusive ride.

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72)
and is there an
exploded diagram of it anywhere? I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

(excellent post snipped, but copied and saved to my hard drive for
reference)

Wow- Thanks!

One question - where did you find any kind of diagram at all? Poking
about the interwebs all I can seem to find is the installation sheet, no
parts list or anything like that (like I've been easily able to find for
conventional hubs, which for the most part I didn't really need them,
because those are simple enough to be self explanatory...)

nate


--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

landotter wrote:
On Oct 18, 3:26 pm, Nate Nagel wrote:
Got to thinking today as I was cleaning yesterday's muck off my bike...

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) Cool!


http://techdocs.shimano.com/media/te...9830608789.pdf

Drive side bearings serviceable. 11 loose bearings. Top up with some
thick grease and forget about it for a year.

Thanks. Where the heck did you find that? I still can't figure out
what kind of sequence of clicks to use to get that from Shimano's web
site, but there it is.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Oct 18, 7:26*pm, Nate Nagel wrote:
landotter wrote:
On Oct 18, 3:26 pm, Nate Nagel wrote:
Got to thinking today as I was cleaning yesterday's muck off my bike....

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? *I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! *I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) *Cool!

http://techdocs.shimano.com/media/te...e/EV/bikecompo...

Drive side bearings serviceable. 11 loose bearings. Top up with some
thick grease and forget about it for a year.

Thanks. *Where the heck did you find that? *I still can't figure out
what kind of sequence of clicks to use to get that from Shimano's web
site, but there it is.

I just entered via the northern European gate and went to the techdoc
link.

Nate Nagel wrote:
landotter wrote:

snip

http://techdocs.shimano.com/media/te...9830608789.pdf


Drive side bearings serviceable. 11 loose bearings. Top up with some
thick grease and forget about it for a year.

Thanks. Where the heck did you find that? I still can't figure out
what kind of sequence of clicks to use to get that from Shimano's web
site, but there it is.

It's simple, dawn each morning, sacrifice 2 chickens, and paint the
walls with caterpillar **** before dealing with the Shimano Gods,
works every time!

On Oct 18, 5:56*pm, landotter wrote:
On Oct 18, 7:26*pm, Nate Nagel wrote:



landotter wrote:
On Oct 18, 3:26 pm, Nate Nagel wrote:
Got to thinking today as I was cleaning yesterday's muck off my bike....

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? *I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! *I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) *Cool!

http://techdocs.shimano.com/media/te...e/EV/bikecompo....

Drive side bearings serviceable. 11 loose bearings. Top up with some
thick grease and forget about it for a year.

Thanks. *Where the heck did you find that? *I still can't figure out
what kind of sequence of clicks to use to get that from Shimano's web
site, but there it is.

I just entered via the northern European gate and went to the techdoc
link.

The US Shimano site is just useless, only listing the top few groups
of each range. There's loads of Shimano stuff that QBP sells that
_does not exist_ according to the Shimano USA site.

If you want any good info at all, always go to the European site.

On Oct 18, 4:26 pm, Nate Nagel wrote:
Got to thinking today as I was cleaning yesterday's muck off my bike...

first of all I need some smaller brake pads so I can clean them without
removing them or pulling the front wheel (don't want my wheels to wear
out any sooner than they have to)

but the real question is, how hard is it to repack the bearings in a
Shimano DH3 series dynohub (I think mine is the N72) and is there an
exploded diagram of it anywhere? I should probably do that every now
and then if I'm going to keep riding in less than perfect weather, but I
don't know if there's any Special Instructions to cracking one open.

Didn't ride today because I spent the afternoon cleaning bike and
installing my new rear wheel (took a little longer than you'd think
because I had to fiddle with brakes; all my other wheels are narrower) I
finally have appropriate, matching wheels! I think that I can call this
bike "done" just as soon as I get a better headlight. (and do whatever
I'm going to do with the brakes.) Cool!

nate

--
replace "roosters" with "cox" to reply.http://members.cox.net/njnagel

I am a newby, but if the Shimano dynohubs cost 90$ and last for 15km
how does one justify paying 200$ for the Smitt? hub?

On Oct 19, 11:32*am, john dean wrote:


I am a newby, but if the Shimano dynohubs cost 90$ and last for 15km
how does one justify paying 200$ for the Smitt? hub?

You can ask that question about almost any bicycle component on the
market. You can get a Shimano crankset for less than $100, or you can
get a Shimano crankset for about $700. The second will not make you
measurably faster than the first.

Schmidt hubs have the reputation for lowest drag, highest efficiency
and most reliability. Apparently, people that are fond of riding in
competitive, all-day-all-night self-supported randonneuring events are
very happy to spend money for a hub and headlight that gives all the
light they need for as long as they need it, with minimum drag on the
bike.

And some people just like having what they believe is the world's
best, whether it's hub generators, guitars, hunting knives, art work,
whatever. Personally, I tend to go toward the "good enough for me"
category.

- Frank Krygowski