Opinions on Shimano 10spd 7800 rear hubs



R

Ron Ruff

Guest
Wondering if those that have experience with these could tell me if
there are any significant issues with the new freehub in regard to
durability, sealing, maintenance, etc. Thanks.
 
Q

Qui si parla Campagnolo

Guest
Ron Ruff wrote:
> Wondering if those that have experience with these could tell me if
> there are any significant issues with the new freehub in regard to
> durability, sealing, maintenance, etc. Thanks.


Seems durable, MUCH harder to overhaul, getting the 3/16 balls to sit
nice when you put them in(loose, no cage ala Campagnolo). Races are
pressed onto the axle, so if you toast one, new race/axle
assembly-$50..same for the front. I think the 7700/6600/6500 are much
better hubs, since the freehub is bolted onto the hub body. Not the
unsupported one like the 7800 and all others out there. BUT getting
tough to find 7700 hubs and remember, 7800 hubs are '10s' shimano
only...
 
R

Ron Ruff

Guest
Thanks for the info Peter. I saw some new 36 hiole on ebay for $70 each
and wondered if there was a serious issue that I didn't know about.
Sounds like they are decent at least. Heck, they are as light as a lot
of boutique hubs. I'm not going to ride them myself (I'm still on 9spd)
but I wanted to try a 2-1 spoking pattern (like Campy G3) and these
should be perfect for that.
 
R

Ron Ruff

Guest
Ron Ruff wrote:
> Thanks for the info Peter. I saw some new 36 hiole on ebay for $70 each.


Now they are $60!
 
Q

Qui si parla Campagnolo

Guest
Ron Ruff wrote:
> Ron Ruff wrote:
> > Thanks for the info Peter. I saw some new 36 hiole on ebay for $70 each.

>
> Now they are $60!


Undoubtedly the seller, listening to many MO places, are thinkin' 36h
is hopelessly outdated and to be discontinued by manufacturers at any
minute..wrong on both counts. Great find, even if you are gong to do a
goofy lacing pattern.
 
J

jim beam

Guest
Ron Ruff wrote:
> Thanks for the info Peter. I saw some new 36 hiole on ebay for $70 each
> and wondered if there was a serious issue that I didn't know about.
> Sounds like they are decent at least. Heck, they are as light as a lot
> of boutique hubs. I'm not going to ride them myself (I'm still on 9spd)
> but I wanted to try a 2-1 spoking pattern (like Campy G3) and these
> should be perfect for that.
>

if you're looking at radial spoking for the non-drive side, you might
experience flange failure. check the hub and see if shimano list it as
ok for radial spoking. for normal spoking counts, the tension ratio
drive to non-drive for a campy hub is about 50%. for a half-count
non-drive side, the spoke tension will be about the same both sides.
that might exceed the flange's ability to cope in a radial configuration.
 
R

Ron Ruff

Guest
jim beam wrote:
> if you're looking at radial spoking for the non-drive side, you might
> experience flange failure. check the hub and see if shimano list it as
> ok for radial spoking. for normal spoking counts, the tension ratio
> drive to non-drive for a campy hub is about 50%. for a half-count
> non-drive side, the spoke tension will be about the same both sides.
> that might exceed the flange's ability to cope in a radial configuration.


I would cross them if I could... but it wasn't obvious to me how I
could do that with an odd number of spokes, unless maybe a
crows-foot... that is in sets of 3, yes? I'll have to look into it...

Shimano says that the front hub is ok for radial (even with 36 holes I
guess), but no mention on the back. I'm not really worried though...
the flange is pretty big and I'm only using every other hole.

Like Peter said, a 36 hole DA hub is not a big seller, since the only
advantage it has on Ultegra is lighter weight... plus it has some
disadvantages... and if you want a 36 spoke wheel you probably aren't
too concerned about the weight. It's the perfect hub for doing a 2:1
lacing though since the tension on both sides will be nealy identical.
It seems pretty optimal for a light & strong wheel... if you want to
use a deep rim anyway.
 
J

jim beam

Guest
Ron Ruff wrote:
> jim beam wrote:
>> if you're looking at radial spoking for the non-drive side, you might
>> experience flange failure. check the hub and see if shimano list it as
>> ok for radial spoking. for normal spoking counts, the tension ratio
>> drive to non-drive for a campy hub is about 50%. for a half-count
>> non-drive side, the spoke tension will be about the same both sides.
>> that might exceed the flange's ability to cope in a radial configuration.

>
> I would cross them if I could... but it wasn't obvious to me how I
> could do that with an odd number of spokes, unless maybe a
> crows-foot... that is in sets of 3, yes? I'll have to look into it...
>
> Shimano says that the front hub is ok for radial (even with 36 holes I
> guess), but no mention on the back. I'm not really worried though...
> the flange is pretty big and I'm only using every other hole.


the every other hole thing will probably help, but you still have stress
aligned with the path of least fatigue strength. see how it goes.
maybe buy two just in case since the price is right...

>
> Like Peter said, a 36 hole DA hub is not a big seller, since the only
> advantage it has on Ultegra is lighter weight...


the bearings are slightly better and the shell is cold forged which
makes it stronger, both static loading and fatigue. good hub.

> plus it has some
> disadvantages... and if you want a 36 spoke wheel you probably aren't
> too concerned about the weight. It's the perfect hub for doing a 2:1
> lacing though since the tension on both sides will be nealy identical.
> It seems pretty optimal for a light & strong wheel... if you want to
> use a deep rim anyway.
 
R

Ron Ruff

Guest
jim beam wrote:
> the every other hole thing will probably help, but you still have stress
> aligned with the path of least fatigue strength. see how it goes.


> the bearings are slightly better and the shell is cold forged which
> makes it stronger, both static loading and fatigue. good hub.


Like you said... should be a strong hub anyway. As I recall they used
to advertise a thicker flange compared to the 7700 model... but maybe
I'm mistaken. I'd put the odds at flange failure real close to zero...
but I can do a crows foot on that side if it seems warranted.

> maybe buy two just in case since the price is right...


I bought 10! Part of a little wheel building project... planning to
build them up and sell them. I don't aim to make money... just doing it
for the experience.

BTW, where does one get boxes and packing materials to ship wheels?
I've been checking generic boxes online, and the smallest box I could
fit 2 wheels in costs 3 times as much to ship to me as the boxes cost!
It's just over the limit where they have to go freight vs UPS. There is
no place locally to get the right size. But I'm thinking there must be
places that sell boxes and dividers that are already made for wheels.
Peter... would you mind me asking where you get yours... or do you make
them yourself?
 
Q

Qui si parla Campagnolo

Guest
Ron Ruff wrote:
> jim beam wrote:
> > the every other hole thing will probably help, but you still have stress
> > aligned with the path of least fatigue strength. see how it goes.

>
> > the bearings are slightly better and the shell is cold forged which
> > makes it stronger, both static loading and fatigue. good hub.

>
> Like you said... should be a strong hub anyway. As I recall they used
> to advertise a thicker flange compared to the 7700 model... but maybe
> I'm mistaken. I'd put the odds at flange failure real close to zero...
> but I can do a crows foot on that side if it seems warranted.
>
> > maybe buy two just in case since the price is right...

>
> I bought 10! Part of a little wheel building project... planning to
> build them up and sell them. I don't aim to make money... just doing it
> for the experience.
>
> BTW, where does one get boxes and packing materials to ship wheels?
> I've been checking generic boxes online, and the smallest box I could
> fit 2 wheels in costs 3 times as much to ship to me as the boxes cost!
> It's just over the limit where they have to go freight vs UPS. There is
> no place locally to get the right size. But I'm thinking there must be
> places that sell boxes and dividers that are already made for wheels.
> Peter... would you mind me asking where you get yours... or do you make
> them yourself?


A biie shop that deals in wheels should have them. Or we use a frame
box, fits 2 wheels really well.

WE warranty more than a few using a frame box, then get wheel boxes
with the warranty retirn. Or some shop that deals with Kry-4-me-syriums.
 
S

SYJ

Guest
Ron Ruff wrote:
---snip---
I'm not going to ride them myself (I'm still on 9spd)
> but I wanted to try a 2-1 spoking pattern (like Campy G3) and these
> should be perfect for that.

---/snip---

Ron,
Are you thinking about skipping holes on your rim, or matching
used spokes to rim hole count. If the latter, you're pretty much stuck
with a 32 hole hub (16 DS 8 NDS). If the former, well, I guess it
doesn't matter.

SYJ
 
R

Ron Ruff

Guest
SYJ wrote:
> Ron,
> Are you thinking about skipping holes on your rim, or matching
> used spokes to rim hole count. If the latter, you're pretty much stuck
> with a 32 hole hub (16 DS 8 NDS). If the former, well, I guess it
> doesn't matter.


Not quite sure what you are asking. It is a 36 hole hub, and I plan to
use all 18 holes on the DS and 9 radial (hopefully) on the NDS. I'll
use a 36 hole rim, skipping every 3rd hole... so the rear will have 27
spokes. Even if I used a 32 hole hub and 16:8 I'd still use a 32 hole
rim and skip every third hole. Rims are drill with holes canted towards
alternating sides, so I don't think it would be a good idea to do it
any other way.

Here is one person who did it a little differently... but I don't agree
with his approach.
http://wellspokenwheels.com/wsw5.htm
For one thing he used a 24 hole rim and a 32 hole hub, so unless he had
the rims custom drilled, some of the holes in the rim aren't lined up
properly. Plus he used a narrow spaced AC hub which has close to
balanced tension with *normal* lacing. He says that removing half the
spokes from the ND side balances the tension but I don't see how that
could be true. The Dura Ace hub has wide spacing, so if I lace radial
heads in on the NDS, and 3x on the DS the tension is nearly identical
with 2:1 spoking.
 
S

SYJ

Guest
Ron Ruff wrote:
> SYJ wrote:
> > Ron,
> > Are you thinking about skipping holes on your rim, or matching
> > used spokes to rim hole count. If the latter, you're pretty much stuck
> > with a 32 hole hub (16 DS 8 NDS). If the former, well, I guess it
> > doesn't matter.

>
> Not quite sure what you are asking. It is a 36 hole hub, and I plan to
> use all 18 holes on the DS and 9 radial (hopefully) on the NDS. I'll
> use a 36 hole rim, skipping every 3rd hole... so the rear will have 27
> spokes. Even if I used a 32 hole hub and 16:8 I'd still use a 32 hole
> rim and skip every third hole. Rims are drill with holes canted towards
> alternating sides, so I don't think it would be a good idea to do it
> any other way.



Ron,
I kinda figured out what you intended to do (skipping holes on the rim)
as I was writing my post, but for some stupid reason, I posted anyway.
I've thought about a similar project, but was going to follow the
'wellspoken' path - 32 hole hub, 24 hole rim. One of these days...

SYJ
 
R

Ron Ruff

Guest
SYJ wrote:
> I've thought about a similar project, but was going to follow the
> 'wellspoken' path - 32 hole hub, 24 hole rim. One of these days...


Are you concerned about the way the holes are drilled in the rim... or
do you plan to "fix" it somehow?

I guess some people might think it looks "funny" to have unused holes
in the rim, but if the rim doesn't have eyelets I think it will be
barely noticable.
 
S

SYJ

Guest
Ron Ruff wrote:
> SYJ wrote:
> > I've thought about a similar project, but was going to follow the
> > 'wellspoken' path - 32 hole hub, 24 hole rim. One of these days...

>
> Are you concerned about the way the holes are drilled in the rim... or
> do you plan to "fix" it somehow?
>
> I guess some people might think it looks "funny" to have unused holes
> in the rim, but if the rim doesn't have eyelets I think it will be
> barely noticable.


Purely for aesthetic reasons. I'm silly that way.

SYJ