hub bearing pre-load?

Quoted message said:

ok. i ahve a new front shimano hub that's factory machine set. bump
bump bump go the bearings erk erk erk goes the cone thump thump
thump...how else would the machine know, right?

Usually the factory setting is right IME.

Quoted message said:

how much to slack off from the machine set bump bump bump to get to the
Jobst Brandt FAQ pre-load wherein the balls are forced up against the
cone/hub and stay there without slack or axle wiggle even out at the
rim!!?
this apparently in the long run reducing wear and run out.

Adjust so there is a little play when the hub is out of the frame. Put
the wheel in the frame and tighten the QR as normal. There should now
be no play at the rim but the wheel should self-rotate so the heaviest
spot - usually the rim joint unless you use long stem valves - is at the
bottom. Repeat until perfect.

Nutted or bolted hubs can be adjusted out of the frame. Slightly
tighter than "no play" is best, but the wheel should still self-rotate
in the frame.

Cartridge bearings are normally non-adjustable and some hubs (e.g.
Schmidt dynamo hubs) may allow a little play at the rim. See what the
hub manufacturer says.

Quoted message said:

ill effests?

A severely-tight hub will cause noticeable vibration (which you can feel in
the frame while spinning the hub, particularly the front hub, which won't
have a ratchet mechanism adding to the noise.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

I saw a Park Tool article on this... You clamp it to the outside of the
fork and tighten the QR. This gives you access to a cone and locknut
while simulating the pressure mounting the wheel presents.

Quoted message said:

ok. i ahve a new front shimano hub that's factory machine set. bump
bump bump go the bearings erk erk erk goes the cone thump thump
thump...how else would the machine know, right?

how much to slack off from the machine set bump bump bump to get to the
Jobst Brandt FAQ pre-load wherein the balls are forced up against the
cone/hub and stay there without slack or axle wiggle even out at the
rim!!?
this apparently in the long run reducing wear and run out.

I've got a Shimano XT M730 front hub that come lose from
time to time. I tighten it till the side to side play goes away.

quote='Zog The Undeniable said:

ok. i ahve a new front shimano hub that's factory machine set. bump
bump bump go the bearings erk erk erk goes the cone thump thump
thump...how else would the machine know, right?

Usually the factory setting is right IME.

Quoted message said:

how much to slack off from the machine set bump bump bump to get to the
Jobst Brandt FAQ pre-load wherein the balls are forced up against the
cone/hub and stay there without slack or axle wiggle even out at the
rim!!?
this apparently in the long run reducing wear and run out.

Adjust so there is a little play when the hub is out of the frame. Put
the wheel in the frame and tighten the QR as normal. There should now
be no play at the rim but the wheel should self-rotate so the heaviest
spot - usually the rim joint unless you use long stem valves - is at the
bottom. Repeat until perfect.

Nutted or bolted hubs can be adjusted out of the frame. Slightly
tighter than "no play" is best, but the wheel should still self-rotate
in the frame.

Cartridge bearings are normally non-adjustable and some hubs (e.g.
Schmidt dynamo hubs) may allow a little play at the rim. See what the
hub manufacturer says.[/QUOTE]

The Stein axle vise works great for this.
jastein.comTools for Wheels.htmOpen ↗
Dan

In a surprising interval of lucidity said:

Quoted message said:

ok. i ahve a new front shimano hub that's factory machine set. bump
bump bump go the bearings erk erk erk goes the cone thump thump
thump...how else would the machine know, right?

Zog The Undeniable wrote:

Quoted message said:

Usually the factory setting is right IME.

Really??? I don't think I've ever encountered a Japanese QR hub that
came from the factory anywhere near correctly adjusted.

If they were shipped correctly adjusted, it would make wheelbuilding
more difficult, since most truing stands don't supply sufficient axle
compression to remove the slack in the bearings.

This is an issue somewhat related to lawyer lips and vertical dropouts.

With newer frames that share these features, you can get by with the QR
adjusted much looser than was needed with traditional frame designs.

You can _get by_ with looser tension, and correspondingly tighter
beaaring adjustment, but that doesn't mean you should...

See: http://sheldonbrown.com/cones

Sheldon "Not Too Tight, Not Too Loose" Brown
+----------------------------------------------------+
| War is God's way of teaching Americans geography. |
| -Ambrose Bierce |
+----------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

good advice all!
the operative information here is the machine sets the bearings AGAINST
THE CONE slamm and then stops screwing the cone in.
which gives the bump bump bump at your finger tips revolving the axle.
now to pin this down
do we remove all the bump bump bump?
or half the bump bump bump leaving some bump bump bump in there
or remove all the bump bump bump (assuming shimano is producing
roundness)

Jobst Brandt on preload in the BB strongly suggest there should be some
BUMP BUMP BUMP or do I read FAQ incorrectly? I'm using a bit of BB bump
bump bump with some success tell you next week.

Quoted message said:

good advice all!
the operative information here is the machine sets the bearings AGAINST
THE CONE slamm and then stops screwing the cone in.
which gives the bump bump bump at your finger tips revolving the axle.
now to pin this down
do we remove all the bump bump bump?
or half the bump bump bump leaving some bump bump bump in there
or remove all the bump bump bump (assuming shimano is producing
roundness)

Jobst Brandt on preload in the BB strongly suggest there should be some
BUMP BUMP BUMP or do I read FAQ incorrectly? I'm using a bit of BB bump
bump bump with some success tell you next week.

With a hight quality BB using grade 25 BB's there is no BBB. Even
when adjusted quite tight, by old record unit has no BB BB BBB. So
maybe the assumption you mention is incorrect, in which case a little
BB BB preload would lead to BBB.

yes, what you're driving at follows thru here. the BB has a different
slope and surface area and a long heavy shaft visavee the hub. my
shimano BB has ten thousand on it with harris 25 bearings and
pwood/finishline every year. the span of torque from pre-load to bump
bump bump is broader than the smaller hub units which demonstrate a
sharper more narrow adjustment range. right?

from the hi mileage hi load use i've given two rear hubs- one standard
3 pine tree or delta and one deore lx-it looks like the tight
adjustment promotes less wear than the looser "let the axle wiggle a
little" approach.
a race forms and the bearings run it the race rather than wander
hither and yong creating a random and therefore ahem elliptical surface
that is per se unadjustabull.
off course the problem is one of tough and feel-how much is too much?
and that's the reason for my bump bump 1/2 bump bump or no bump
as the bearing bump bump is a mutually experienced staring point

Quoted message said:

from the hi mileage hi load use i've given two rear hubs- one standard
3 pine tree or delta and one deore lx-it looks like the tight
adjustment promotes less wear than the looser "let the axle wiggle a
little" approach.
a race forms and the bearings run it the race rather than wander
hither and yong creating a random and therefore ahem elliptical surface
that is per se unadjustabull.
off course the problem is one of tough and feel-how much is too much?
and that's the reason for my bump bump 1/2 bump bump or no bump
as the bearing bump bump is a mutually experienced staring point

The tight approach probably works best with relatively soft cones.

Quoted message said:

good advice all!
the operative information here is the machine sets the bearings AGAINST
THE CONE slamm and then stops screwing the cone in.
which gives the bump bump bump at your finger tips revolving the axle.
now to pin this down
do we remove all the bump bump bump?

Yes, remove all of it.

Indeed, if you read Sheldon's article back there, you should have some
*play* that goes away when you tighten the QR at the proper torque.
Zinn also says this.

If you have a little roughness (bump bump bump) it get exacerbated when
you tighten the QR, which compresses the bearing. And once the wheel is
on the bike, you don't feel the roughness, but it's there, and it will
eat the cones.

--
BMO

Boyle M! et al

More from NEW hub bump-

Ok,let's move away from using the bearing bump bump bump as a model
and go for-
FEELING THE BEARINGS REVOLVE ON THE CONE AND HUB SURFACES but not
rotating the wheel and not feeling the bearings on the
surfaces-that's too loose, gives axle play.

To augment the feeling the bearings on the surface comes the local
master mechanic idea of using a stethoscope, a pipe, and feeling the
bearings revolve.

Also usable is your head. Place the forehead on the axle or frame.
Rumble rumble.

Seems a lot of work goes into the Q/R problem.

I tour so both axles are solid-the longest Wheels Mfg axle on the rear
and a Wheels 9mm solid "track" axle on the front. How one Tour's
using a Q/R idunno as the Q/R's bend right off.

The falling weight using the wheels imbalance at nipple or rim joint
sounds like an excellent idea for used or worn hubs. I cannot recall
getting anywhere near that tight where the wheel is actually in a
stationary position without bearing bump bump bump or rumble and bump.

Are you adjusting a worn hub assembly? That's eccentric not round
then adjusting the cones at the assembly's narrowest dimension? The
rotation would then come to probable stop at the ellipsis's wider
dimension then fall thru the imbalanced weight going toward the
circumference bottom?

That's good used hub adjustment!! Use the head or scope.

The "breaking it in" idea-slowly off course-produces a groove in
the newly round assembly then the bearings, mil spec grade 25 ( I
assume there are inexpensive grade 25) then the bearings stay there for
a while continuing wearing in a more or less round orbit: that's
pre-load, right?

But if yawl start off in a loose fit where the axle wiggle then the
assembly immediately wears elliptically with one short side one long
side and every time the bearings wander over onto the long side the
wear factor grows-exponentially?

Choose one.

Leads to the idea that maybe yawl should replace the break in bearings
with new ones but then I have doubts about getting the new replacements
into the old groove and keeping them there with a new adjustment.
Sounds like one for U. of Mich. Engineering or Stamford. Looks like mil
spec 25.

A tricky try is cleaning the axle's threads adjacent the cone nut
(pick a side and loosen that one? Or figure what Barnett is telling you
about sequential side tightening)), flood threads with green seep in
between locktite, backing off the new hub nut and cone, to the feel the
revolutions and leter set up. Now, to convince Shimano to save $$ by
reducing the locktite strength on the uh right side.

The idea of shoving the axle nuts from one side to the other, the other
side ditto seems essential for deore rear hubs after using OLD
freewheel hubs. Some repacks DO NOT TIGHTEN THE OTHER NON-DRIVE SIDE.
The non-drive side needs forceful setting and spinning, like drive side
up, before and during the drive side cone adjustment.

Jim Smith said:

Quoted message said:

Good advice all! The operative information here is the machine
sets the bearings AGAINST THE CONE slamm and then stops screwing
the cone in. Which gives the bump bump bump at your finger tips
revolving the axle. Now to pin this down do we remove all the bump
bump bump? Or half the bump bump bump leaving some bump bump bump
in there or remove all the bump bump bump (assuming shimano is
producing roundness).

Quoted message said:

Quoted message said:

Jobst Brandt on preload in the BB strongly suggest there should be
some BUMP BUMP BUMP or do I read FAQ incorrectly? I'm using a bit
of BB bump bump bump with some success tell you next week.

Quoted message said:

With a hight quality BB using grade 25 BB's there is no BBB. Even
when adjusted quite tight, by old record unit has no BB BB BBB. So
maybe the assumption you mention is incorrect, in which case a
little BB BB preload would lead to BBB.

You can't feel the difference beteen grades of bearing balls that come
into consideration. The roughness comes from cup and cone finish that
is nowhere near that of bearing balls.

[email hidden]

Quoted message said:

Jim Smith said:

Quoted message said:

Good advice all! The operative information here is the machine
sets the bearings AGAINST THE CONE slamm and then stops screwing
the cone in. Which gives the bump bump bump at your finger tips
revolving the axle. Now to pin this down do we remove all the bump
bump bump? Or half the bump bump bump leaving some bump bump bump
in there or remove all the bump bump bump (assuming shimano is
producing roundness).

Quoted message said:

Quoted message said:

Jobst Brandt on preload in the BB strongly suggest there should be
some BUMP BUMP BUMP or do I read FAQ incorrectly? I'm using a bit
of BB bump bump bump with some success tell you next week.

Quoted message said:

With a hight quality BB using grade 25 BB's there is no BBB. Even
when adjusted quite tight, by old record unit has no BB BB BBB. So
maybe the assumption you mention is incorrect, in which case a
little BB BB preload would lead to BBB.

You can't feel the difference beteen grades of bearing balls that come
into consideration. The roughness comes from cup and cone finish that
is nowhere near that of bearing balls.

That makes perfect sense. It was bogus to blame the bottom bracket
bearing balls for the bump bump bump.

"You can't feel the difference beteen grades of bearing balls that
come
into consideration. The roughness comes from cup and cone finish that
is nowhere near that of bearing balls."

right-another attempt to reduce factors
hidden hear is the question-who sez all grade 25 bearings are created
equally? are the US grades more 25 than the asia 25 bearings?
maybe this is non cycle applicable rocket science but with the preload
approach a few bucks for a quality 25 beats an inferior 25 3 steps to
the long and twisting road.
do you know the quakesat people? is their antennae coupled to a IC
timer
rather than relying on wavelength only for processing?

why is this?? and whose soft cones, whose hard cones?

Quoted message said:

"You can't feel the difference beteen grades of bearing balls that
come
into consideration. The roughness comes from cup and cone finish that
is nowhere near that of bearing balls."

That's because the surface is to be burnished by the balls as they
wear-in to the cups and cones. The balls create their own precision
surfaces, creating in effect, "matched" cups and cones.

If you were to check the hardness of the cups and cones with a Rockwell
checker, they'd be well under the hardness of the balls themselves.

BTW, burnishing is done the same way with roller bearings to finish the
inside of hydraulic cylinders, among other things.

Quoted message said:

right-another attempt to reduce factors
hidden hear is the question-who sez all grade 25 bearings are created
equally? are the US grades more 25 than the asia 25 bearings?

Grade 25 is grade 25. It makes no difference. Steel balls wear pretty
much the same. If you're looking for a tighter tolerance, get some
Grade 20. That's as close as you're going to get for steel balls.

However, if you're looking for some fancy-schmancy balls, go here:

http://www.hooverprecision.com/html/hoover_-__ceramic__silicon_nit.html

Timken/Torrington has some fancy cartridge bearings based on these balls:

http://www.timken.com/industries/torrington/products/fafnir/superprecision.asp

A nice chart for tolerances:

http://www.steelmedia.com/steel-balls-grades.htm

--
BMO

Jim Smith said:

Quoted message said:

Jim Smith <[email hidden]> writes:

Quoted message said:

Quoted message said:

Quoted message said:

With a hight quality BB using grade 25 BB's there is no BBB. Even
when adjusted quite tight, by old record unit has no BB BB BBB. So
maybe the assumption you mention is incorrect, in which case a
little BB BB preload would lead to BBB.

You can't feel the difference beteen grades of bearing balls that come
into consideration. The roughness comes from cup and cone finish that
is nowhere near that of bearing balls.

Quoted message said:

That makes perfect sense. It was bogus to blame the bottom bracket
bearing balls for the bump bump bump.

Binding bottom bracket ball bearings bother bespectacled bikers. Blasphemy!

--
Dave
dvt at psu dot edu