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Torque values; BMW Airhead Motorcycles
Copyright, 2014, R. Fleischer
torquevalues.htm-71B

Be sure to read part 71A, if you have not previously,
before using this part 71B.


Torque values between systems of measurement:
    Nm x 0.7378 = foot-pounds
    foot-pounds x 1.356 = Nm
    Mkp x 7.23 = foot-pounds
    inch-ounces = 141.6 x Nm    
    Mkp x 9.81 = Nm
    Foot-pounds x 192 = inch-ounces

    ONE inch-pound is the same as 1.1525 CmKg, or 0.1129 Nm
    ONE Ncm is 0.0885 inch-pound.


 

Bolt head sizes----Caution!
In some circumstances BMW is now shipping bolts with ONE wrench size smaller
heads, using the ORIGINAL part numbers.  A dealership MIGHT have BOTH sizes
in the same box on their shelves; or, you order a bolt and get one with a different
head size than you expected.  You likely do not have 18 & 16 mm wrenches in
your Airhead tool kit! I have seen 18 mm being substituted for 19 mm; 16 mm for
17 mm.  K bikes don't generally have this problem...most started with the even
numbered sizes.  Later model BMW motorcycles are using the smaller heads.
There is no need to carry extra and new sizes of wrenches, if you are careful
and knowledgeable...and, now you ARE!


Nuts, bolts: grading systems & standard torque values:
Fittings from Germany are specified by a different grading system from that
used in the U.S. (for American SAE items).   Fittings from Germany are Metric;
bolts are marked on the heads by a number that corresponds to the over-all
strength rating. 

Ratings (grades) used in this DIN system FOR BOLTS & SCREWS are, in
increasing order of strength:  5.6; 6.8; 6.9; 8.8; 10.9; and 12.9.  The 8.8 is a
fairly strong metal, & is quite common on BMW's.  Whilst 8.8 is commonly
available now in hardware stores, many such stores carry INFERIOR bolts,
often unmarked...and in SOME instances you can NOT depend on any
markings it may have.   BMW uses some bolts rated even stronger than 8.8
in SOME PLACES....shock absorber mounts, brakes, rods, crankshaft-to-
flywheel...etc.   I suggest using BMW-supplied parts!  In some instances
BMW uses specially made/treated/ETC items. Don't even think about using
non-BMW fasteners for the driveshaft U-joint, flywheel, rods....

There are standardized tables for recommended tightening torque for fasteners.
Once in a while those tables need to be consulted.  The tables have the size
of the fastener (M6, M8, M12, etc.) & optimum tightening torque for the grade.
BMW put pages containing the tables, into its Factory Service Manuals. In the
DIN (German standards) system, bolts & nuts are assumed to be phosphate
treated, no after-treatment, not galvanized.
   There is, or may be, information
on oiled versus not oiled.  Separate or included in the same tables may be
information if the steel parts are cadmium plated, or otherwise treated.
(approx. 30% less is the recommended torque for cadmium plating).  Cadmium
plated parts are hardly available anymore in/from Europe.  Tables are different
for NUTS; nuts are rated as 8, 10, & 12 in strength....with the same sort of
variances for plating, lubrication, etc.  Thus, a nut & bolt may have slightly
different ratings.   As a general rule, there are some sort of standards for all
he various types of headed screws, bolts, etc.  
If no specification by BMW
for your specific fastener/location, you use standard table values.
 

I DO HAVE the BMW factory manual TABLES for "common hardware" torque
values, strengths, etc.  These are specific to types & sizes and 'treatments' of
such as bolts, but NOT specific for any place on your bike they are used at.  I
have thought about copying the charts and making them available by link in this
article, but haven't found a real need so far.

 

Cadmium plating:
BMW is shipping parts that are NO LONGER cadmium plated due to European
environmental rules.  These non-plated parts tend to RUST!   These parts are
treated & nearly always OK at the original specified torque as used with them
when they were cadmium plated, assuming the original specs used are in Nm. 
Try to obtain old original parts...in most instances (?) the part numbers are the
same, & the dealership might have the cadmium plated ones under the SAME
part number, or, sometimes, so will be or might be in the SAME box...ASK.  
 
SOME of these parts may need anti-seize, so be cautious.

LOCTITE:
With clean & dry threads MOST types of Loctite cause UP TO ~15% increase
in actual torque as Loctite acts as a very mild lubricant>>> this is typically the
maximum effect. Because of the safety factor of parts strengths & typical
usages, this effect of Loctite is usually ignored, as far as torque wrench
settings are concerned. 


ANTISEIZE COMPOUND: 
When using antiseize compound...you
should
, and in many instances such as spark plug threads MUST, allow for the
change in effective torque (18-30% with antiseize compound). USUALLY the
only place on your Airhead you need to reduce the torque for, if the item has
antiseize compound on it, is at the spark plugs.  I am a bit more anal about the
subject, and tend to reduce torque some, with anti-seize compound, at such
as the bolts/studs that hold the transmission to the engine, and some other
places.  
Never-ever use any antiseize product at the wheel bolts,
nuts, cone fittings, etc., that hold the REAR wheel to the rear drive. 
This means the Monolever and Paralever bikes!!

 


BMW/Clymers/Haynes/ETC... literature errors
for torque values when listed in foot-pounds:
(BMW original errors are often carried forward into Clymers & Haynes books)

BMW of North America published a Service Bulletin, Volume II, NO. 23, Dated 3/82.    
I will quote some from that bulletin:
"May we advise you that from now on, any published BMW conversions found in brackets
immediately behind the millimeter figures in all service literature (riders manuals, shop
manuals, etc.)
should not be used.  Recent experience has shown that use of these
figures has caused some major, expense errors by either a dealer service department,
a customer, or an independent machine shop.   Please inform all customers upon
purchase of a shop manual, and also those customers that you are aware
of that have one in their possession."   This was signed by Herb Neas, National
Service Manager.

There are errors above if you are a strict interpreter (millimeter should be metric Nm
for instance).  
What all this REALLY means:
When BMW has a published torque figure, it is 'usually' OK as shown in Nm,
(I say
'usually' because sometimes I think BMW torque values at SOME PLACES
are somewhat too high) but do
NOT use BMW's foot-pounds figures.
  I
suggest that you calculate those yourself (Nm x 0.74 is foot-pounds). 
Clymers, Haynes, etc., have used BMW's figures for Nm & foot-pounds & thus MAY
have continued to carry forward the errors!....so be cautious.   I personally know of
errors in even the Factory Workshop Manuals.....see article on this website: 
http://bmwmotorcycletech.info/torquespecs&problems.htm

Torque figures in the rest of this article, below, are values
Snowbum uses, & believed to be best/proper... & safe.
 


There have been instances in which someone has questioned just what BMW
means by its torque figures.  This question usually arises because using a
torque wrench at the limited clearance area of the driveshaft bolts requires
an adaptor, and BMW does sell their version of this adaptor...which 'can' add
to the working-length of the torque wrench, thereby INcreasing the true bolt
torque value, from that set on the torque wrench......unless the adaptor is used
at 90.  When this question comes up, it almost always is in regards to the
tightening method for the 4 driveshaft bolts, that hold the U-joint flange to
the transmission output flange.  I know of no instances, on any BMW motorcycle,
where the factory specification for torque is anything other that the ACTUAL
torque on the fastener.   The torque figure is the value on the bolt itself. This
is standard for industry & applies unless specifically noted to be different.  

The torque to be applied to the bolt is the factory specified torque, and you
MUST calculate the adjustment factor for the torque wrench, if the adaptor
is not used at 90 to the torque wrench.
  In every instance, except at 90, the
torque wrench will need to be set at a value LESS than the value of the actual
torque applied to the bolt head.   Be sure you understand this, & CHECK the
torque applied in several ways. 
 See article 71A on how to do this.


Section 11-Engine:

    Cylinder heads:  Evenly cross-torque, staging at ~10, ~18, & then CAREFULLY to a final
    value of 25ftlbs. I ALWAYS use a final value target of 25 foot-pounds for ALL models...even
    though I know PRE-Nikasil models were specified at 29-31 foot-pounds in old literature.   I
    do NOT consider it safe to torque higher than a TRUE 25 foot-pounds on ANY model, & 
    that is with a KNOWN GOOD, CALIBRATED torque wrench.   The 4 rocker arm nut threads
    are to be oily, and if they squeak, remove nut, oil immediately, & immediately re-tighten.  
    After the first torqueing after the heads have been off, for each later re-torqueing, back off
    the
2 head nuts only a very small amount, a tiny fraction of one turn, one nut at a time, &
    re-torque. Do same for all 4 rocker nuts, back off about 1/4 to bit more of a turn, one at a
    time unless doing end play work (then do both nuts of ONE rocker at one time).   The idea
    is that you will not have more than one or two of the nuts loose, in comparison to the others,
    for very long.   Time is involved, as I think the metal will move some over time, so don't leave
    things unbalanced and loose.

 
   Spark plugs:  the BMW specification is 16-18 foot-pounds for clean & dry threads for the
    3/4 inch reach stock top plugs. SOME old manuals will show values as high as 21.7.  
DO
    NOT
use such high values!!    When using (or if previously used) anti-seize compound,
    reduce the 16-18 foot-pound figures; I use about 14-15 foot-pounds.  For those with
    dual-plug conversions, you might have short 1/2" reach or the 3/4" reach plugs at the bottom,
    depending on if a spacer is being used; or welding/machining was done; & what size plug
    was installed.  For 3/4" reach 14 mm bottom plugs which must be used with welding &
    threading, use the same values as for the top plugs.  If an untheaded 1/4" spacer is being
    used, I suggest using ~14 ftlbs. For bottom 1/2" reach
14 mm plugs, use 12-14 foot-pounds
    on clean and dry threads....be very cautious, & use about 10-12 foot-pounds if anti-seize
    is used; you may have to increase this SLIGHTLY to get a good contact/crush on the crush
    washer.  If you have
12 mm 1/2" reach bottom plugs, use a bit less and with anti-seize compound. 

    Anti-seize compound works into metal, so be cautious if you install spark plugs without such
    compound if the compound was used previously.   Doing it by feel on a fresh crush washer
    works adequately, provided you are not ham-fisted. I always recommend a torque wrench.
    

    M6 nut on the end of the automatic advance unit on models up through 1978: 
    4 foot-pounds, which is 48 inch-pounds.  Be careful! 
DO NOT USE NOR DEPEND on the
    accuracy of a 75 or 100 foot pound clicker wrench at such a low setting (even if it can be
    set that low).  DO NOT USE SUCH A FOOT-POUND WRENCH.  Use EXPERIENCED
    hand feel, or do it with an INCH-POUND or equivalent low torque values wrench.  Going
    over 48 INCH-pounds is not necessary.  It is good to use a FRESH waverly
    washer. It is not terribly UNusual to find that someone has over-torqued this nut; yet the
    camshaft threaded stub end is not yet broken (& maybe not yet cracked).  Thus, the
    threads could already be weakened.    
Be very cautious.  I always torque this nut by my
    experienced hand, with a very small 4 (max 6) inch wrench. If you do not have a good
    feel for torque, especially torque that breaks things, use a torque wrench.
  Use
    30 INCH-pounds to start with, and preferably a fresh waverly washer.  My personal 
    limit as shown is 5 foot pounds; and when that is multiplied by 12 that means 60
    INCH-pounds. I recommend 48 INCH-pounds maximum, as shown above.  If you have an
    INCH-OUNCE wrench, guess how you calculate inch-ounces?   Yes, the conversion
    factor is near the top of this page.    Your day is ruined if you snap off the tip! 
    SO: be very careful!!!   See cams article:  http://bmwmotorcycletech.info/cams.htm


    Rocker arm adjustment lock nut: 13-16 foot-pounds (some say 12, & I agree)

    Valve cover center acorn nut: 14 foot-pounds (I am cautious, & do it by feel). LOOK
    at the far inner end of this associated stud.  It is next to the spark plug. If ALL the
    threads of the head are not engaged by the stud, you must decide if to remove the stud
    and reset it deeper (if the acorn nut will still have enough threads engaged); or, install
    BMW's LONGER stud, which BMW supplies just for this purpose
    (see:  http://bmwmotorcycletech.info/hardware.htm)

    Outer cover, front of engine:  about 5.5 foot-pounds

    Engine to frame:  55 foot-pounds is reasonable, all models, although there are
    differences on the books, with much lower in places, down into the thirties. 
    I prefer 55 foot-lbs..

    Crankshaft rod bolts:  ALWAYS use new ones; 36 foot-pounds.  Special tri-tool needed,
    see tools article:  http://bmwmotorcycletech.info/tools.htm
    R80GS, R80R, R100GS, R100R:  15 foot-pounds, then 40 degrees more.

    Flywheel bolts:  ALWAYS new ones are recommended, but NEVER reuse the early
                                  smaller /5 & early /6 type bolts
, all of which were 10 mm diameter:
 
                           /5       44 foot-pounds, clean and dry threads, which means they can
                                      have a faint glaze of oil from your cleaning solvent.

                         
1974:  Two specs, 45 ftlbs for R60 & R75, then 53 ftlbs on R90 series, 
                                       but I simply use 52-55 foot-pounds for all these models for 1974 with
                                      10 mm bolts.


                  All values except for the 10 mm bolts, above, can be clean & dry, or,
                  lightly oiled.  Both ways are safe, for the models BELOW, using 11 mm bolts        

                         

                         
                          1975:  & later, 11 mm bolts:  80 foot-pounds is my personal maximum. For this,
                                      I have the threads, male & female, clean & appearing dry, but there
                                      could be a faint sheen from very slight oiliness. 

                                    For just the 1981 & later:
                                    BMW's last specification change is in S.I. 11-049-91 (2495); this can
                                    also be seen on the 12/92 fiche on page 3, illustration G23.  The SI
                                    stated that while the flywheel bolts were previously at ~75 foot-pounds
                                    (100 Nm), they were now to be at 90 foot-pounds (125 Nm), cleaned
                                    threads, & the threads were then to be OILED!  BMW specifically said
                                    that the bolt limits would NOT reach their limit of elasticity at that torque,
                                    & could be REUSED!
I will NOT tighten them that tight.  Makes me very
                                    nervous!  However, some Pro's do, & I have heard of no problems reported.
                                    It is YOUR CHOICE.  NOTE also that this is in regards to the 11 mm bolts,
                                    & applies to 1981+ models....certainly not the smaller /5 & early /6  10 mm bolts
                                    which need replacement upon each use, which un-stretched 11 mm do not, &
                                    those 10 mm bolts in the /5 & early /6 are absolutely not to be torqued to such
                                    high values.  

                                    There have been a lot of different specifications on flywheel bolts over the
                                     years.  I use about 80 ftlbs, clean and dry threads, or, I might have a faint
                                     oily sheen residue from oily solvent. Am I OK with 75-80 ftlbs on well-oiled         
                                   
 bolts: YES.

    Oil cooler hoses 17 mm banjo nuts (located at the oil filter outer cover:  absolute
                                     maximum 14.5 foot-pounds.  I suggest 13 foot-pounds, rechecked overnight. 
                                     HINT:  do not let outer hose be in contact with the fairing if you have a fairing.
                                     Vibration might loosen the banjo.  Lower hose ends fittings should not contact
                                     anything except the thermostat fitment area.   HOLD the hose banjo bolt
                                     METAL end while tightening the banjo bolt (by a 17 mm socket or can be box
                                     end wrench), so that the banjo assembly does not rotate during tightening &
                                     touch what it shouldn't.  
ALWAYS new 4 brand-new gasket-washers!  BE
                                     SURE to check for leaks after next engine startup.


    Oil pan mounting bolts:  book values 6.5-8 ftlbs (some books show to 8.5). I suggest LESS,
                                     perhaps 5.5-6.  Carefully tighten in a staggered cross-pattern, starting at the
                                     center ones.  Do tightening very evenly. NO GOO!  Put the lettered side UP.
                                    There is supposedly a heat-activated glue on these.  The old cork gaskets are
                                    NLA.  I sometimes do these bolts BY HAND using a 4 or 6 inch wrench & not
                                    a torque wrench.   MOST torque wrenches of the type that have a range of
                                    maybe 5 to 75 foot-pounds, can
NOT be used for this, as their low-setting
                                    accuracy is NOT good, NOR is the FEEL OR SOUND for the click. If you
                                    use a torque wrench, use an INCH-pound or other more sensitive wrench.
                                    I recommend 66 to 72 INCH-pounds.
HINT! Before removing the pan,
                                    TIGHTEN all the bolts to about 80 INCH-POUNDS.  If they tighten properly,
                                    good.  If they show signs of bad threads, note which ones, so you can fix
                                   
the threads with a Helicoil, after the pan is removed.


    Engine oil pan drain:  20-22 foot-pounds (book values have been variously from 20-25).  I
                                             use the low side of specification for this pan drain bolt.


    Oil filter inner cap bolt: 15-20 foot-pounds (some books may say 30, I think that is too high).

    Oil filter outer cover plate:  no matter if thermostat or GS or plain:  not over 7.5 foot-pounds.
                                             I always do these by FEEL, not a torque wrench.  Tighten them in stages,
                                             evenly, back and forth.  NO NEED to have them too tight! USE
                                             LOCKWASHERS.

    Oil canister central pipe:  Install with Loctite, quite tightly, using a custom-made mandrel or
                                             carefully ground very broad thick tipped screwdriver.  On the cooler
                                             models, leave the end 3 mm proud of the engine outside wall surface. 
                                             Allow the Loctite a day or two to cure.  

    Oil pressure sending switch:  no specification on early models, later models from about
                                             1985 or so specify 25 Nm, or 18 foot-pounds.  Use 12 point deep
                                              socket, moderately tight by feel.  Do NOT over-tighten. DO NOT
                                              use anything but a socket, or you can distort the switch case, and
                                              it MIGHT then leak/weep oil.

    Oil pickup bolts:  6.5 foot-pounds, Loctite BLUE.  I use a sealant at the gasket(s).

    Oil PUMP cover:   88 INCH-pounds; probably 72 is enough.   LOCTITE BLUE.  If you have
                                     Phillips screws replace the cover with the updated version, same for bolts.
                                          Read about that at FlywheelRemoval.htm

    Camshaft flange bearing & front main bearing:  11-13 foot-pounds, but some models
                                                                                            from about 1985 are 18 foot-pounds.

    Chain cover:  5.2-5.9 foot-pounds (62-71 INCH-pounds).  I may go a bit higher.
        
    
Section 12-Engine electrics:

   
Spark plugs:  see Section 11, above.

   
Centrifugal advance: old style, single M6 nut on end of camshaft, see section 11.

   
Starter motor bolts:  35 foot-pounds is the published specification, but this is probably
                                    excessive. 
Be very cautious that the starter is solidly &
                                    squarely in place as you tighten.   Read:
                                    http://bmwmotorcycletech.info/boschvaleostarter.htm
                                            (which covers several other brands too).
  Especially
                                    read the last area of that article, with the photos of interferences.

   
Alternator rotor allen bolt:
  book value is 16.6-19.5 foot-pounds, I suggest ~14 as a maximum.
                                               The rotor-to-engine-crankshaft are taper-fits. The mating surfaces must
                                               be absolutely clean & free from any contamination, including oil, even
                                               fingerprints. Do NOT use gasoline in cleaning the tapers.

    

Section 13/16-Carburetors & associated air & fuel inlet parts:
  
Top covers: These can have Phillips OR OTHER similar cross slot screws.  See tools
                             and also the carburetor's articles about these screws, for removal, for
                             the particular screwdrivers needed, and removal techniques if frozen.


   
Cylinder head stubs:   10 foot-pounds, Loctite RED. NOTE:  I do this by feel, & the torque I use is
                                        likely rather higher than 9, although I have never measured it.  Heat the head,
                                        & freeze the stub.  At assembly time: add Loctite RED.  Use a
                                        strap wrench or other tool, and QUITE TIGHT! 



Section 18-Exhaust system:

     Exhaust pipe finned nuts:
  Prior to 1981 the specification was 101-130 foot-pounds, later
                                                 went to 145-159 foot-pounds.   I have seen even higher published
                                                 figures for 1981+.  
There is NO GOOD REASON to have these
                                               
nuts so tight.  There are steel split rings that clamp nicely inside the
                                                finned nut, on the pipe, so there is NO REASON for such tightness.
                                                I don't know how tight I put them, but I suspect it is not over 90 ftlbs.  I
                                                never use a torque wrench, I always do it by feel, a decent grunt,
                                                using a proper finned wrench.  NOT too tight, & I ALWAYS use a LOT
                                                of anti-seize compound.  Failure to loosen these nuts & to clean the
                                                threads & to
use fresh anti-seize compound on the threads yearly will
                                                eventually cause you a lot of anguish.  Clean and coat the rings too.
                                                Rings should have their splits towards the head, that is, the tapers should
                                                face each other.  I use a brass brush to clean the threads, rather than a
                                                steel brush.

                                               
If, in loosening a finned nut, it suddenly binds-up, then do NOT
                                                go further trying to loosen with more force.  By using heat, & a
                                                penetrating oil (acetone & ATF automatic transmission fluid
                                                50-50, shake before using), several times, maybe over a week's
                                                time, you may be able to remove the nuts withOUT cutting them!
                                                Try SLIGHT tightening & loosening, as appropriate, flooding the
                                                threads as best possible. Heating the nut/port area before
                                                applying the acetone/ATF fluid, will help, as it may draw-in
                                                the fluid as it cools.

                                                If the finned nut will not come off, after all the above is tried, Do
                                                NOT FORCE IT.  CUT the nut off!  The nut is MUCH CHEAPER
                                                than replacing the port threads! Having to cut off the finned nut,
                                                or forcibly loosening & thereby ruining the port threads, will NOT
                                                happen if you REGULARLY maintain them, and
do not
                                                over-tighten them!  There is an article on this website,

                                               
http://bmwmotorcycletech.info/exhaustnuts.htm
.  LOTS more
                                                information in that article.  Use of a considerable amount of
                                                an anti-seize compound is MANDATORY!!!   Cutting the nuts
                                                off requires a
special technique.

      Exhaust system 'clips'....pre-silencer (1985+):  15 foot-pounds
    


Section 21-23 Clutch & transmission:

   
Transmission drain:  14-18.5 foot pounds, I suggest the lower figure.

    
Transmission fill:   20-22 foot pounds, I suggest the lower figure.

   
Transmission to engine:  about 15 foot-pounds, somewhat more is OK.  Books values from
                                            14-24 depending on the book (1981+ is 24 foot-pounds)....and some
                                             confused Nm with foot-pounds.

   
Transmission shifter lever:  13 foot-pounds

   
Transmission cover screws:  6  foot-pounds

   
Transmission output flange-to-U-joint:  26 foot-pounds.  Requires an adapter tool. Bolts
                                                                   are sturdy & strong, & a feeling of 'good & tight' from a
                                                                   common 6" 12 point box end wrench is probably OK.
                                                                   DO NOT use the split lockwashers that were supplied
                                                                   on earlier models except in emergency if you don't have the
                                                                   shorter replacement bolts. This website has the number for
                                                                   the proper slightly shorter bolts, which are NOT used with
                                                                   washers.  Install the proper bolts clean, dry, &
1 drop of
                                                                   Loctite BLUE on the threads before assembly.
                                                                   
SEE section 26, below, for expanded information.

   
Transmission output flange center large nut:  148-173 foot-pounds, probably OK to even 190.
                                                                   absolutely clean & dry (this is a taper fit). Do not clean with
                                                                   gasoline.  I use 160 ftlbs.

       
   
Kickstarter models cotter nut/crank:  15 foot-pounds

   
4 speed transmission shift fork bolts: 17 foot-pounds

   
Clutch lever adjusting screw locknut:  15 foot-pounds is the spec. I DO NOT go that high.

   
Clutch bolts (to flywheel, early models):  16 or 17 foot-pounds is specs up to 1980.  The /5
                                                                     had 14.  From 1981 with the new style clutch, 15-16 ftlbs.

   
Selector fork/cam bracket:  18 foot-pounds (from 1981, 14 foot-pounds)

   
Neutral switch on 5 speed transmissions:   This is not specified. Use a DEEP socket to install
                                                except when your switch has side facing terminals, which prevent
                                                that.    I have not yet decided on a torque setting.
                                                 If I did decide, and forgot to put it here, you would find it here:           
                                                        http://bmwmotorcycletech.info/neutralswitch.htm



Section 26-Driveshaft & swing arm:

   
Driveshaft drain & fill:  10 MAXIMUM foot-pounds is snowbum's suggestion.
        

   
4 Driveshaft U-joint bolts, non-Paralever models:  26 foot pounds MAX, NO lockwashers
                        Use 1 drop of Loctite
BLUE on clean & dry threads.  If you have lock-washers,
                        get rid of them, & use the very slightly shorter later bolts.
   Early models like
                        the /5 were specified at 18 foot-pounds, that was with the longer bolts with split
                        lock-washers.  NO bike should have those long bolts NOR any lock-washers, the
                        18 foot-pounds is listed here as a no-use reference ONLY.  
If one of those old
                        lock-washers breaks, its bolt WILL loosen, the rest soon will & MAY destroy the
                        back side of the the transmission.  If your BMW dealer insists that BMW has
                        gone back to using lock-washers, ignore that WRONG advice; use the
                        shorter, later, bolts!!!!  Do NOT use substitute bolts!  Do NOT use
                        hardware store bolts!     Use 25 foot-pounds as a target value. An adapter
                        is required for your torque wrench, see my tools article & my torque wrench
                        article  http://bmwmotorcycletech.info/torquespecs&problems.htm.

I am adding this note because there have been instances in which someone has
questioned just what BMW means by its torque figures.  This question usually arises
because using a torque wrench at the limited clearance area of the driveshaft bolts
requires an adaptor, which can add to the working-length of the torque wrench,
INcreasing the torque value from that set on the torque wrench...unless the adaptor
is used at 90.   When this question comes up, it almost always is in regards to the
tightening method for the 4 driveshaft bolts, that hold the U-joint flange to the
transmission output flange.   The torque figure is the value on the bolt itself,
whether or not you use an adaptor from the torque wrench to the bolt.
 This is
standard for industry, and applies unless specifically noted to be different.
http://bmwmotorcycletech.info/drvshftboltstoolstorque.htm
http://bmwmotorcycletech.info/IncTorqWr.htm

    Driveshaft coupling nut (bell gear):  180 foot-pounds is the maximum and probably 150 is OK.

   
Swing arm allen-recess adjusters:  These large threaded pins with the allen center hole are
                                                             to be preloaded to 15 foot-pounds, then backed off slightly,
                                                             then finished in only the tightening direction, leaving them at
                                                             7.5 (9 max) foot-pounds.  At the same time you must end up
                                                             such that spacing from swing arm to frame point is equal,
                                                             within ~.015" is best.

   
Swing arm adjuster 27 mm (or 1-1/16") lock nuts (STEEL nuts):
  72-77 foot-pounds. 
                                                            Use a properly squared off & proper outside diameter socket.  
                                                            See http://bmwmotorcycletech.info/tools.htm

   
Paralever:
       
Preloading the pivot shafts:  15 foot-pounds, then, back off, then retighten to 7.5 foot-pounds;
                                                               locknuts to 75-80 foot-pounds

        
Left-hand bearing pivot stub:    110 foot-pounds

       
Right-hand bearing pivot shaft:  5.5 foot-pounds

       
Right-hand bearing pivot shaft lock nut: 
77 foot-pounds

       
BMW specifies using locking compounds on the stubs and nuts.  See my other articles for what I
            think about that, and which to use.

          

 
Section 31/32-Steering, forks, bars, controls on bars:

    Fork drain nuts:  16.6-18.6 foot pounds.  Probably one should just use 17 foot pounds for all to 1980.

   
Top cap nut, center tube, also called Crown Nut and Centering Nut:  approximately 80-95
                                                   foot-pounds; some books say 88-96 foot-pounds.
  
    T
op of fork tubes 'nut' and top spring retainer:  ~80 foot-pounds.

   
R80R, R100R, GS, top sleeve/locknut: 48 foot-pounds

   
M8 x 1 nut at the bottom of some forks, that holds the damper:  ~15-17 foot-pounds.
  
   
Lower fork yoke stanchion clamp (lower triple clamp):  25 foot-pounds.  Some variances, see your book.

   
Bottom caps on the lowers:  specifications have varied, some say 59-73 foot-pounds; others say
                                                  87-93 foot-pounds, I do it by feel.

   
Damper (rod retainer nut):  early bikes 17 foot-pounds; 1981 and later 25 foot-pounds

   
Piston plugs:  18 foot-pounds

   
Damper slider tube, and force brace, 1985+:  11 foot-pounds

   
Axle clamp bolts (pinch bolts):  about 10-12 foot-pounds

   
Axle nut:  25 (35 maximum) foot-pounds

   
Axle, late models, that use an allen bolt and not a nut:  25 foot-pounds

   
Clamp ring bolt:  8 foot-pounds

   
Fender brace upper:  16 foot-pounds

   
Fender brace, lower: 1.5-1.8 foot-pounds

   
Fork brace, GS:  13 foot-pounds

   
Fork filler plugs:   Varies with models: 6.5-10 foot-pounds

   
Handlebar nuts: 
15 foot-pounds
    

    Steering bearing preload adjustment:  This should be done by road test, per my instructions
                                                 elsewhere's on this site.  But, there IS a specification, and it is 30 (+-2)
                                                
INCH
-pounds.  This is the force to continue moving the entire fork, after
                                                 once started moving.  If you INSIST on using a torque wrench for this,
                                                 ask me how to modify your existing tool tray dogbone tool.

    


Section 33-Rear Drive and rear shock absorbers:

   
Rear drive drain: 23 Nm max.  I use a somewhat lower value.

   
Rear drive fill:  20 Nm max. I use a somewhat lower value.

   
Later models rear drive oil level inspection plug:  This is only found on late models, & is
                                 a small 10 mm hex bolt located half-way up/down the REAR arc of the rear
                                 drive. BE CAREFULL!...   7-1/2 Nm, or 5.5 ftlbs, MAXIMUM.  Fresh washer! 
                                 Do it by feel, be careful.  If using a torque wrench, use an accurate sensitive
                                 wrench, such as an inch-pound wrench.
                                 Some never remove this plug, fearing they will strip the threads.
                                
I almost never actually use a torque wrench on this inspection hole
                                 bolt/plug; doing it by educated feel.  I have NEVER stripped one.


   
Rear drive to driveshaft housing:  35 foot-pounds is what I use on these 4 nuts.   There
                                are differing specifications for them in the various literature.  Up through 1984,
                                but excluding the G/S and ST, 47 Nm (35 foot-pounds).  The G/S & ST in some
                                books are shown as 65 Nm (48 foot-pounds). Generally, the books show most
                                1985 (some from 1986) models to use 55 Nm (40.5 foot-pounds). ASK ON
                                THE AIRHEADS LIST ABOUT 'GOO', because most of the early models used
                                paper gaskets, but much later models did NOT use gaskets, instead using a
                                sealant.  The sealant was a retainer compound, rather than a drying goo, &
                                BMW used an uncommon Loctite...although several Loctite types will do OK.
                                

   
Shock absorbers:  25 foot-pounds.  I use that for all of them, except as below.
   
Shock units, Paralever:  26 foot-pounds
   
Shock units, Monolever before 1987:  34 foot-pounds; then 21 +-3 foot-pounds on later
                                                 Monolever models

   
Input gear (pinion) large nut, Loctite blue: /5/6  75 foot-pounds.  After /6, use 110-115 ftlbs.
       
Bevel drive pinion retaining nut, R80GS, R80R, R100GS, R100R:   150 foot-pounds
         
 cover housing: 15 foot-pounds
       
   oil filler/level plug:   17 foot-pounds...I use less.
       
   oil drain plug:  17 foot-pounds...I use less.
 
   
The threaded ring that surrounds that input gear:  75+ foot-pounds, threads Hylomar'd.

    Left side cover plate on the rear drive:  14 foot-pounds

   
Torque arm, front to frame:   32 foot-pounds

   
Torque arm, rear to housing:
   25 foot-pounds
 


Section 34-Brakes:

   
Brake caliper plugs (plugs on the bottom of the swinging ATE calipers 1974-1980):  
              43.3-46.6 foot-pounds.  The 'book' says that the ATE swinging caliper caps are to be 45
              foot-pounds for the /6 and only 30 for the /7.  Why?
   
   
Brembo calipers (& ATE that are NON-swinging):  Book says 22-23 foot-pounds except
                that the ST & G/S should be 26 ftlbs.   These values are for the bolts that mount the
                caliper to the fork legs.  

   
Brake caliper joining bolts, R80R, R100R:  inner 22 foot-pounds, outer 7 foot-pounds

   
Brake lines (pipes):  6 to 7 foot-pounds (11 maximum from 1981, I think that too high).  
                        I suggest you be careful and not over-torque these.

   
Disc brake mounting nuts/bolts:
  17 foot-pounds.   For R80GS, R80R, R100GS, R100R
                                                                  use  24 ftlbs.
                                                


Section 36-Wheels and axles (& see section 31/32, above):

    
Front and rear axle nuts:   in most books as 32.5-34.5 foot pounds.  I use 30 ftlbs

   
Axle pinch bolts: front 11-12 foot pounds, rear 11-13 foot pounds; late 1984+ use 17 foot pounds
                                on both pinch bolts; but I do not use quite that much.
 
   
Mono-lever models (& Paralever, including R80ST, R80 G/S, R100GS, etc); rear wheel bolts:
         
                  Models have been made for both three & four bolts/nuts.  

                          
NEVER EVER oil NOR antiseize these threads...NEVER!
....ONLY clean & dry
                           threads.   Use 63 foot-pounds for the R80ST, & a bit more, perhaps 75-77
                           for the G/S & 85+ models.  Pay attention to what your particular bike's
                           torque specifications are, some are higher.  USE BMW's Owner's Book values!!!

                          
Section 46-to ?   Frame, fenders, braces, saddlebag bracketry, fairings,
                              special lighting equipment, battery bracketry, instruments
                              pods, centerstands, etc.:

   
Center-stand:  25-26 foot pounds (I suggest closer to 31 on 1985+ models). There are variances,
                            as the type of bolt/nut, etc., has varied.  Check your owners booklet.  Many late
                            models used 17 mm bolt/nuts & 29 Nm torque.

   
Side-stand center pin, from 1981:  13 foot-pounds

   
Rear subframe:
  11-18 foot-pounds



BAND-CLAMPS, NON-BMW:
    It is NOT commonly known that screw-type band-clamps have torque values.  The type of band-clamps
    I am referring to here are NOT the type that BMW used to use at the U-joint rubber bellows (small
    screw, very fine threads); whether screw or clamp pliers types.  What I am referring to here are the
    AFTERMARKET band clamps that have multiple cross-wise small slots almost all the way around, that
    you may be tempted to purchase for various things, & substitute for the original types.  The standard
    torque setting for these aftermarket clamps depends on the width of the band.  Frankly, there are no
    places on BMW motorcycles for these types of clamps, but I know some of you will use them anyway.
        5/16" width band:  14 to 16 INCHpounds
        1/2" width band:  25 to 35 INCHpounds
        9/16" width band: 30 to 40 INCHpounds

    There are special clamp versions used for high pressure fuel injection hose clamps, for you
    K bike owners, and you really should use those Oetiker types.   When the liquid flowing inside the
    hose is under a goodly pressure, you can have a LEAK at the hose-to-metal-pipe junction, if you
    use regular aftermarket band-clamps, because they tend to distort the hose as you tighten the clamp.
   
    For the carburetor band clamps, BMW DOES use screw type clamps, and moderately tight is correct.

 



    
What is posted in this article above IS believed correct, but no guarantees as to that!

Revisions:
Initial edit and release:  07/05/2004
12/16/2004:  Clarify torqueing cylinder head nuts in section 11
02/26/2005:  layout, url, copyright, hyperlink
07/16/2006:  add note on calibrating the wrench
08/20/2006:  editing for clarity
01/09/2009:  Updated
04/25/2009:  clarify crankshaft bolt torques, to eliminate any chance of misunderstandings.
07/15/2009:  clarify rear drive to driveshaft nut tightness; minor other typos or unimportant
                       clarifications
10/24/2009:  clean up the article
10/15/2012:  Add QR code, add language button, update Google Ad-Sense code
04/23/2013:  Change cover from 5.0 foot-pounds.
09/25/2013:  Clean up cam tip nut torque wording.
03/10/2014:  Clarify, condense
10/02/2014:  Prep for smaller devices, and clean up some.
10/25/2014:  Add note #1 near top of page, and later in section 26.
08/15/2015:  Clarify and expand a small amount here and there....and more on 08/16/2015, with some corrections.
10/11/2015:  Add additional comment & cautions to oil cooler hose banjo bolts. Font size increased. Narrow the
                    article. Update Meta-codes, clean up article and clarify a few things.

 

Copyright, 2014, R. Fleischer

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