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Conference noted::bicycle

Title: Bicycling
Notice:Bicycling for Fun
Moderator:JAMIN::WASSER
Created:Mon Apr 14 1986
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:3214
Total number of notes:31946

2500.0. "Bottom bracket removal" by KRAKAR::WARWICK (Can't you just... ?) Tue Feb 23 1993 13:46

    
    Does anyone want to give (or point me to a previous) tutorial on
    stripping down a (Shimano, non-sealed) bottom bracket for cleaning ?
    I have, or will shortly have, the appropriate tools.
    
    Is it all pretty obvious, or are there any special tricks ?
    
    Trevor
T.RTitleUserPersonal
Name
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2500.12286.13ODIXIE::RRODRIGUEZShake that grits tree!Tue Feb 23 1993 13:595
    Note 2286.13 is a nice one; I imported it to All-in-One
    to have on hand.  It has a very friendly illustration
    too!
    
    r�
2500.2JURA::PELAZ::MACFADYENI wish to register a complaintWed Feb 24 1993 06:4617
First take the cranks off, sometimes a task in itself.

Then unscrew the lockring. You should have the correct tool for this but
you can make do with a screwdriver and gentle use of a hammer.

Then unscrew the removable cup. You need a peg spanner for this, although
you can make do with a small allen key to go in one of the peg spanner holes
and a screwdriver to apply torque between the allen key and the spindle 
(difficult if the removable cup is corroded into place). 

When you removed the bearing cup everything sort of falls apart. Clean in
white spirit, reassemble withe plenty of grease, and if there wasn't one
before, put in one of those plastic sleeves to protect all the greasy bits
from water coming down the seat tube.


Rod
2500.3NOVA::FISHERDEC Rdb/DinosaurWed Feb 24 1993 08:283
    and avoid removing the fixed cup especially if it's Italian.
    
    ed
2500.4WRACK::ZIELONKOThu Feb 25 1993 15:367
>    and avoid removing the fixed cup especially if it's Italian.

why is that?

if you get a clicking in the BB after you've worked on it chances are it's
loosened up and you need to tighten it again. i believe the general rule with
BBs is to err on the side of too tight rather than too loose.
2500.5love that blue stuffGUIDUK::MONINThu Feb 25 1993 19:075
    
    I think I heard that originally as "err on the side of Loc-tite(tm)
    rather than too loose."
    
    Will
2500.6SOOTHING AROUND...WMOIS::GIROUARD_CFri Feb 26 1993 07:184
     I thought it was "human" :-) I know, I know, I just couldn't
    resist...
    
    Chip
2500.7NOVA::FISHERDEC Rdb/DinosaurFri Feb 26 1993 08:0319
    RE: "Italian fixed cup"
    
    So glad you asked.:-) English fixed cups are reverse threaded.  The
    result is that it it were to come loose, the bearing rolling inside
    would not tend to unscrew the cup.  When an Italian fixed cup comes
    loose, the bike is nearly unrideable because the bearings rolling
    inside the cup help it to unscrew faster. With a super record crank
    the cup would be unscrewed in as little as a tenth of a mile.  It
    heppens that with a C Record crank the fixed cup cannot unscrew far
    enough to make the bike unrideable but it sure does cut down on your
    speed.
    
    It might appear that this can only happen if the cup was not tightened
    enough in the first place, but there are a few other causes.
    
    (and my cluster is pretty well hung so I had plenty of "spare time"
    for writing this.)
    
    ed
2500.8Scottish threadedMOVIES::PAXTONEdinburgh-Penicuik '93Fri Feb 26 1993 08:2814
    Having some fixed-cups of each handedness is particularly fun
    when you're trying to remove one on the other side of an upside-down
    bike with a 15-inch spanner (or similar WoMaD) and you can't decide
    whether it won't budge because:
    
    a) You're not leaning hard enough on the lever
    b) You're turning it the wrong way
    
    The trick is to stop assuming (a) before you strip the threads.
    
    By the way (.7) how does one quantify a well hung cluster ?
    
    ---Alan
    
2500.9NOVA::FISHERDEC Rdb/DinosaurFri Feb 26 1993 09:221
    i dunno but it's not "up"
2500.10WRACK::ZIELONKOFri Feb 26 1993 11:128
>    RE: "Italian fixed cup"

thanks for the info. i thought *all* fixed cups were reverse threaded for
the reason you cited. obviously i've never owned a bike with an italian BB as i
regularly break the whole thing down and have never had the "Paxton dilemma".

i'll pencil in a note in my circa 1975 "Glenn's Bicycle Repair Manual" section
on BB overhaul. gee, maybe it's time to get a new bike repair manual.
2500.11FRIPP::HARRISAll this plus a whammy barFri Feb 26 1993 13:2825
To add to .2 ...

When you put everything back together, you should try to get
the axle flanges and bearing races as close together as possible
without binding them.  This keeps you from crumbling your
bearings over time, and makes the axel spin nicely. 

A neat trick to 'tuning' this is to assemble the bottom bracket
with the adjustable cup screwed in well enough so that the axle 
spins, but doesn't shimmy from side to side.  Screw on the lock
ring, but don't tighten it.  Then, attach the right crank.
With the crank attached, line it up with the chain stay, and,
holding the crank by the pedal end, see if you can move it back
and forth from the stay.  If it moves, then you need to screw
the adjustable cup in just a bit.  If not, then start screwing
down the lock ring. You'll need to try it a few times before
you get just the right setting.

By checking for movement at the end of the crank, you get a more
accurate feel of how well the bearings fit against the axle flange
and cup races.  A friend of mine at a bike shop showed me this.

Hope this helps,

Jim
2500.12Italian or French?IDEFIX::HEMMINGSLanterne RougeMon Mar 01 1993 04:1410
I have a horrible suspicion that it's French brackets that are Right-handed,
but I could be wrong - the whole thing is a farce, anyway.  I have an Alan frame
ostensibly Italian but French threaded - this means that the bracket is RH both
sides and is 35mm x ?mm pitch, instead of the well-known English or BSA 1,375 in.
x ??tpi.  Not only is the outside diameter of the thread slightly bigger, the
pitch is different and so is the thread form!!!

PS The headset is 25mm x 1mm as well, but you just ask for "French threaded".
PPS Add to the old saw "Know thyself" - "know thy velo as well".
PPPS Once you find out - mark the cups appropriately.
2500.13Sealed BB hasslesJURA::PELAZ::MACFADYENI wish to register a complaintMon Mar 01 1993 05:1323
I have slightly different BB hassles (not woes). When I got the Stronglight
chainset last August I coughed up for the Stronglight sealed BB unit too,
not that cheap at around Fr300. This BB is a sealed cylinder threaded
along its entire length, with two lockrings to secure it in place in the
BB shell of the frame.

The main problem I had was turning the damn thing to screw it in (the thread 
engages with one side of the BB shell). Once the unit is well into place,
there's a lot of friction between it and the BB shell. It's very hard
to get a grip on the unit that doesn't damage the threading. 

And of course I didn't realise till later that really the ends of the frame
BB shell should be chamfered to allow the also-chamfered lockrings to locate
the BB unit perfectly. But I've found that keeping the lockrings done up tight
seems to work fine.

Operationally no problems! But I'm not looking forward to ever taking the
thing out. My opinion is that this unit is a problem to install without
special tools (are there things for gripping threads without damaging them?),
and the requirement to do metalwork on the frame isn't that attractive either.


Rod
2500.14NOVA::FISHERDEC Rdb/DinosaurMon Mar 01 1993 08:044
    .12:  French BB's may also be right hand threaded but Italian's
    certainly are.
    
    ed, who still rides his Gueci�tti, Ci�cc and Masi.
2500.15Er , well , yes...IDEFIX::HEMMINGSLanterne RougeMon Mar 01 1993 08:588
Am I confused?  My frames all seem to be different - come to think of it, the
Vitus is French but has BSA (British) threadings, LH thread on fixed cup.  My old
training Raleigh is British throughout, except that you have to buy it a French
handlebar stem, the others are too big.....  I don't think ANY of the seatpins
are the same either.  It's a hard life.

Rod, the Vitus is ready chamfered, but what would you expect coming from the land
of Mavic and Stronglight cassette brackets?
2500.16NOVA::FISHERDEC Rdb/DinosaurThu Mar 04 1993 08:5811
    It just occurred to me to look in my Sutherland's which for
    some reason is in my office and not next to my bikes.
    
    Italian and French and some Swiss bottom brackets have right
    handed fixed cups, except for Motobecanes which follow the
    left handed Swiss Standard.
    
    And then there's a note on how to tell if the bottom bracket for
    a French cottered crank is left or right and blah blah blah...
    
    ed
2500.17What to use for degreaser??KYOA::BOYLEDirty Jobs Done Dirt CheapFri Mar 05 1993 09:446
    What is it that you guys clean this stuff with?  Is there any grease
    cutting liquid I should avoid?
    
    Thanks in advance,
    
    Jack Boyle  dtn 323-4448
2500.18NOVA::FISHERDEC Rdb/DinosaurFri Mar 05 1993 13:164
    Avoid gasoline!  Kerosene's pretty good.  Lately I've been using
    the citrus degreasers which are supposedly environmentally friendly.
    
    ed
2500.19LACQUER THINNER= NASTYWMOIS::GIROUARD_CFri Mar 05 1993 13:535
     I use lacquer thinner. I like it because it blows grease away and then
    evaporates in minutes. It's tough on the skin and very hostile to the
    environment.
    
     Chip
2500.20WRACK::ZIELONKOFri Mar 05 1993 19:3919
to clean the grease off the spindle and the cups just use a paper towel. no
solutions are needed.

if the spindle is hollow you can clean out the middle with a pipe cleaner.

if your bearings are in retainers. just put them roller side down onto some
news paper and roll them around until they leave no trace on the paper.

if you're cleaning your chainrings while you're at it, you can (carefully)
scrape the gunk that accumulates under the chainring teeth with an old screw
driver. then use whatever solution you choose (i use the vetta citrus cleaner
and it works *really well*.) to get the rest of the yuk off. it's easiest if you
take the chain rings off the crank arm. then you can soak them in an old baking
pan in only a small amount of solution. scrubbing with a tooth brush works well
for me.

when reinstalling the cranks on the spindle you want to make sure that the
tapered part of the spindle onto which the cranks fit is free of grease the idea
being that grease on the spindle allows you to overtighten the crank arms.
2500.21PAKORA::GGOODMANSat Mar 06 1993 06:207
    
    
    A mixture of petrol (whatever you foreigners want to call it...) and
    paraffin (or any other silly name that "you lot" have got to use to be
    different...)  :*)
    
    Graham.
2500.22JURA::PELAZ::MACFADYENyou can't fool weMon Mar 08 1993 06:0218
.13>  I have slightly different BB hassles (not woes). 

Did I say that? They're woes now. On Saturday I happened to notice that what
looked like a rubber seal around the BB spindle seemed to have worked out
of place, so I pushed it back in with the tip of a screwdriver. In doing
this the lockring wobbled. Wobbled? A lockring? Shome mishtake shurely.
Further investigation showed that the shell of the BB was badly cracked and
that a ring of it, with lockring attached, was virtually hanging off the
rest of the BB. So I took the bike to the shop where I bought the BB and
the guy there is replacing it with a Mavic sealed unit instead, and this
time he'll chamfer the BB shell, so it should be a good installation.

Anyway, this sort of work may provoke may into doing the gearing and wheel
upgrade I've been meaning to do. It's only money after all, I can stick it
on plastic and pretend I haven't really spent anything.


Rod
2500.23NOVA::FISHERDEC Rdb/DinosaurMon Mar 08 1993 07:019
    "the shell of the BB is cracked"
    
    That's like, ahhh, part of the cast shell that attached to the down
    tube and seat tube, right?  Or is it something else?
    
    If the former, I'd be sending it off to Norm Flye to see if he could
    fix it.
    
    ed
2500.24JURA::PELAZ::MACFADYENyou can't fool weMon Mar 08 1993 07:127
Bad wording on my part; nothing that drastic. The Stronglight sealed BB is
a sealed unit and in appearance is a metal cyclinder, threaded along its
length. It's this shell that is cracked, not part of the frame, so we're
only talking about BB replacement, not frame replacement.


Rod
2500.25NOVA::FISHERDEC Rdb/DinosaurMon Mar 08 1993 11:025
    whew...
    
    :-)
    
    ed
2500.26ROWLET::AINSLEYDCU Board of Directors CandidateMon May 06 1996 11:1821
    This is simply a question of curiosity as the repair will be covered
    under warranty...
    
    I was riding my new (1 month old and < 200 miles) Trek 1220 Saturday
    night when I started hearing a clicking noise from the crank area.  I
    stopped and didn't see anything wrong, so I continued on towards home.
    A few miles later, it seemed like the cleats in my pedals were coming
    loose or something as my feet were changing directions with each pedal
    stroke.  I stopped and couldn't see anything wrong with the
    pedals/cleats, but noticed that my crank seemed to be a bit loose in
    the bottom bracket.  As I continued on home, it became difficult to
    pedal properly and I could see the chain rings wobbling back and forth
    with my pedal stroke.  I managed to finish riding home slowly and will
    be dropping the bike off at the shop tonight after work.  All this
    happened in about 10 miles.
    
    Any idea what happened?
    
    Thanks,
    
    Bob
2500.27PCBUOA::KRATZMon May 06 1996 11:356
    New Trek's should have a one piece bottom bracket cartridge that really
    shouldn't do this.  If it's an old style bottom bracket, then perhaps
    the retainer ring got loose and one of the side cups started to work
    itself out.  Course, it could have nothing to do with the bottom
    bracket and just be caused by a loose crank; in that case a simple
    tightening of the crank bolt should work.  .02 K
2500.28loose bottom bracketSMURF::LARRYMon Oct 07 1996 11:1024
2500.29CONSLT::MCBRIDEIdleness, the holiday of foolsMon Oct 07 1996 11:194
2500.30SMURF::LARRYMon Oct 07 1996 11:285
2500.31WMOIS::GIROUARD_CMon Oct 07 1996 12:467
2500.32WRKSYS::FRANTZBurma!Mon Oct 07 1996 13:428
2500.33WMOIS::GIROUARD_CMon Oct 07 1996 15:223
2500.34BUSY::SLABWould you like a McDolphin, sir?Mon Oct 07 1996 15:324
2500.35WMOIS::GIROUARD_CTue Oct 08 1996 06:583