hub bearing pre-load?

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.

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.

How much? Exactly enough to remove all side-to-side play when the wheel is
firmly clamped in the frame, no more. The only way to know how much is to
adjust it bit-by-bit until the play just goes away when clamped. After
awhile you develop a feel for how much that is. Unfortunately, it's easy to
overtighten because you don't feel any ill effects when you spin the wheel
(not initially anyway).

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

wrote in message
ups.com...
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.

ill effests?

wrote:

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.

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.

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

Zog The Undeniable wrote:
wrote:

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.

All the hubs I've bought have been adjusted far too tight.

~PB

wrote:
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.

Does the ideal amount of pre-load vary according to the application? Do
hubs need less than bottom brackets, for example?

It's interesting that Sheldon Brown does /not/ mention accelerated wear
being a potential result of loose cones. I'm much more concerned about
over-tighteing causing wear so I like to have only the tiniest bit of
pre-load for my hub bearings. Play is detectable when QR is partially
open.

~PB

Pete Biggs wrote:
Zog The Undeniable wrote:

wrote:


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.


All the hubs I've bought have been adjusted far too tight.

A long time ago, after burning up multiple sets of cones and balls, I
had figured out that I had been adjusting the bearings too tight - as
tight as what one gets from the factory.

What I do now:

Back off until I can wiggle the axle. Tighten until I have no wiggle,
then back off slightly less than 1/16 of a turn. The bearings on my new
Cannondale 800 (Shimano 550 wheelset) were much too tight. I am sure if
I had left them the way they were, I would have had pitted cones in no time.

--
BMO

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.

wrote:
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.