© Copyright, 2014, R. Fleischer
Read http://bmwmotorcycletech.info/torquespecs&problems.htm if you have not previously, before using this part 71B.
Torque values between systems of measurement:
Bolt head sizes----Caution!
BMW is now shipping SOME 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, perhaps you order a bolt & 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 & new sizes of wrenches, if you are careful & knowledgeable...and, ....now you ARE!
Nuts, bolts: grading systems & standard torque values:
Fittings from Germany are specified by a grading system that is different from what is 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 the German DIN system FOR BOLTS & SCREWS are, in increasing order of strength: 5.6; 6.8; 6.9; 8.8; 10.9; and 12.9. 8.8 is a fairly strong metal, & is quite common on BMW's. While 8.8 is commonly available now in American hardware stores, many such stores carry INFERIOR bolts, often unmarked...and in SOME instances you can NOT depend on any markings it may have. BE CAREFULL! Nuts are a bit different....see later, herein.
BMW uses 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....
DIN (German standards) system, bolts & nuts are assumed to be phosphate
treated, no after-treatment, not galvanized. Separate or included in the same tables may be information if the steel parts are cadmium plated, or otherwise treated; ~30% less torque is recommended for cadmium plated parts. 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. FIRST check this article, and see if I have a value for you!
YES....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 any need, so far. What would then concern me is if YOU used such charts/table values, and not what is in the lower part of this article. The tables can be WAY wrong, for specific items, that BMW has specified the torque for.
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 when they were cadmium plated, assuming the original specs used are in Nm. Unfortunately, there is no information on any of this, NOR any values to use if the parts are removed and reinstalled, which DOES have an effect, sometimes a goodly one, on repeated fastening torque values. Until this is straightened-out (perhaps never), I suggest you use a faint trace of antiseize compound and reinstall at original torque values. 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 and even in the SAME box...SO ASK.
SOME of these parts may need anti-seize, so be cautious.
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, the Universal Joint at the rear of the transmission, and some other places.
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 of words (millimeter should be metric Nm
for instance; and 'from now on'). What all this REALLY means:
There have been NUMEROUS 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 U-Joint bolts usually requires an adaptor, and BMW AND OTHERS sell adaptors...which 'can' add
to the working-length of the torque wrench, thereby INcreasing the true bolt
value from that set on the torque wrench......unless the adaptor is used at 90°.
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. That means: 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 to a value LESS than the specified value.
See article 71A on how to calculate this.
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 some old literature. I do NOT consider it safe to torque higher than a TRUE 27 foot-pounds on ANY model, & that is with a KNOWN GOOD, CALIBRATED torque wrench. The 4 rocker arm nut threads are to be oily, & 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, 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 ~14 to 15 foot-pounds. For 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, I DISLIKE that, is being used, I suggest using not over 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 10/12 mm 1/2" reach bottom plugs, use less & 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 (if it even 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 unusual to find that someone has over-torqued this nut; yet the camshaft threaded stub end is not yet broken (& maybe not yet visibly cracked). Thus, the threads could already be weakened. Be very cautious. I always torque this nut with 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; 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 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 in the head are not engaged by the stud, you must decide if to remove the stud & 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 particular 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 /5 & early /6 type bolts, all of which were 10 mm diameter:
/5: 44 foot-pounds, clean and dry threads, which means they can/should have a faint glaze of oil from your cleaning solvent. Replace with NEW bolts, every time.
1974: Two specs, 45 ftlbs for R60 & R75, then 53 ftlbs on R90 series, but I use 52-55 foot-pounds for all these models for 1974 with 10 mm bolts. REPLACE with new bolts, every time.
1975 & later: 11 mm bolts: 80 foot-pounds is my personal maximum. For this, I have the threads, male & female, clean & appearing dry, but with a faint sheen from very slight oiliness. See 1981 & later, just below, regarding replacing bolts.
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 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. For whatever reason, BMW did not mention much earlier model details.
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. Recheck overnight. Do not let outer hose be in contact with the fairing if you have a fairing. Fairing movement and fairing vibration might loosen the banjo. Lower hose ends fittings should not contact anything except the cover fitment area. HOLD the hose banjo bolt METAL while tightening the banjo bolt using a 17 mm socket and torque 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 engine startup. If you use the aluminum 'gaskets/washers'....they are to be replaced EACH TIME you unfasten the associated banjo, one on each side. If you use the copper ones, I recommend the same, although they can be re-annealed (careful heating) to be softer and mate up OK.
Following numbers have been used:
07-11-9-963-151, A12 x 17-cu These are copper, and note the 17 mm outer diameter.
07-11-9-963-132, A12 x 16-cu These are copper, and note the 16 mm outer diameter.
07-11-9-963-130, A12 x 15, 5al These are the stock aluminum washers, note the 15 mm outer diameter.
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 and starting at a LOW TORQUE. Do tightening very evenly. NO GOO on gasket! Put the lettered side UP. There is supposedly a heat-activated glue on the gaskets. 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/pulling-out threads, note which ones, so you can fix the threads with a Helicoil, after the pan is removed.
Engine oil pan drain plug: 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, as I believe the spec is much too high. Tighten them in stages, evenly, back and forth. NO NEED to have them too tight! USE LOCKWASHERS....either waverly or star type.
Oil canister central pipe: Install with Loctite, quite tightly, using a custom-made or commercially-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 fully 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), Permatex Form-A-Gasket.
Oil PUMP cover: 88 INCH-pounds; probably 72 is enough. LOCTITE BLUE. If you have Phillips screws; replace the cover with the updated version, with a new O-ring, and new proper bolts. It is not just a bolts change, the cover groove dimensions are also changed. More information at: http://bmwmotorcycletech.info/FlywheelRemoval.htm
Camshaft flange bearing & front main bearing: 11-13 foot-pounds, but some models from about 1985 are 18 foot-pounds.
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. http://bmwmotorcycletech.info/boschvaleostarter.htm covers several other brands too). Especially read the last area of that article, with the photos of interferences. VERY particularly see that article if you have ever had a nose cone break, or other mechanical fitment problems. DO IT!
Alternator rotor allen bolt: book value is 16.6-19.5 foot-pounds, I suggest ~14 as a maximum. The rotor is a taper fit to the crankshaft. The male and female mating surfaces must be absolutely clean & free from any contamination, including oil; I even clean off fingerprints. Do NOT use gasoline when cleaning the tapers.
Section 13/16-Carburetors & associated air & fuel inlet parts:
Top covers: These can have Phillips OR OTHER similar (sort-of) cross slot screws. See http://bmwmotorcycletech.info/tools.htm & also the cv carburetor's articles about these screws regarding removal,.... for the particular screwdrivers needed, and removal techniques if frozen, coating of the threads and underside of the screws, ETC.
Cylinder head stubs: I have removed the specification because I do not believe in it. Use Loctite RED. I never do this installation by torque wrench. I do this by feel, & the torque I use is VERY TIGHT, using a strap wrench or homemade tool. To prepare: Heat the head quite hot (at least to water sizzle) & 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, a YEARLY maintenance item!
If, in loosening a finned nut, it suddenly binds-up, then do NOT go further trying to loosen with more force. By using heat, & then 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! I use a mixture of acetone and Kerosene, and then ~~50% ATF oil.....as this mixture is slower to evaporate and thus does a better job, over-all, and you do not have to apply it but once a day. Try SLIGHT tightening & loosening, as appropriate, flooding the threads as best possible. Heating the nut/port area before applying the mixture, will help, as the threads may draw-in a small amount of the fluid as the area 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. Failure to loosen these nuts & to clean the threads & to use fresh anti-seize compound on the threads yearly may eventually cause you a lot of anguish. Clean and coat the rings. When cleaning the rings, clean the gap in the split ring, if you can. I use an old very thin feeler gauge for that. 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.
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+. Problems include INcorrect conversion of Nm to Ftlbs in the literature. The proper figure is 160 Nm, which is 118 ftlbs. 90 is fine, if you want to measure. I NEVER MEASURE.
There is NO GOOD REASON to have these nuts so tight as the official specifications. There are steel split rings (do clean the gap) that clamp nicely inside the
finned nut, on the pipe, so there is NO REASON for such tightness.
don't know how tight I put them, but I suspect it is not over 90 ftlbs. I also clean the pipe if crusty/rough with deposits. 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.
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 & very tight' from a common 6" 12 point box end wrench is probably OK. I always use a torque wrench. 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. Male and female tapers must be absolutely clean and dry. 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
Selector fork/cam bracket: 18 foot-pounds (from 1981, 14 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): /5, 14 ftlbs. /6, /7 through 1980: 16 or 17 foot-pounds. From 1981 with the new style clutch, 15-16 ftlbs.
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 unless you have custom-modified a socket. I have not yet decided on a torque setting. If I did decide, and forgot to put it here, you would find it here:
Section 26-Driveshaft & swing arm:
Driveshaft drain & fill: 10 MAXIMUM foot-pounds is Snowbum's suggestion.
4 Driveshaft U-joint bolts: 26 foot pounds MAX, NO lockwashers (R100GS use 29 foot-pounds). Both bolt & flange threads must be clean and dry before the bolt is installed. Apply 1 drop of Loctite BLUE on the bolt threads. If you have lock-washers, get rid of them, & use the very slightly shorter later bolts.
Early models like the /5, etc., 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.
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 4 U-joint 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°. 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.
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 (use 27 mm or 1-1/16" socket) lock nuts (STEEL nuts): 72-77 foot-pounds. Use a properly squared off & proper outside diameter socket. See http://bmwmotorcycletech.info/tools.htm
Preloading the pivot pins: 15 foot-pounds, then, back off, then retighten to 7.5 foot-pounds; locknuts to 75-80 foot-pounds
Left-hand bearing pivot stub: 80 foot-pounds
Right-hand bearing pivot shaft: 3.5 foot-pounds
Right-hand bearing pivot shaft lock nut: 77 foot-pounds
BMW specifies using exceptionally strong Loctite locking compounds on the stubs and nuts. See my other articles for what I think about that, and which to use. I personally use a less strong Loctite, so they remove easier, but I add witness paint markings.
Section 31/32-Steering, forks, bars, controls on bars:
Fork drain nut: 16.6-18.6 foot pounds. Probably one should just use 17 foot pounds for all to 1980.
Fork drain BOLT (SIDE BOLT style as on later models): 6 to 7 foot-pounds (8 to 10 Nm).
Top cap nut, center tube, also called Crown Nut and Centering Nut: approximately 80-95 foot-pounds; some books say 88-96 foot-pounds.
Top 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 Be sure you know what this is.
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!... spec: 7-1/2 Nm, or 5.5 ftlbs, MAXIMUM. Fresh washer! I do it by feel, being 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. I use LESS than spec on torque.
Rear drive to driveshaft housing: 35 ft-lbs is what I use on these 4 nuts on the twin shock models. There are differing specifications for them in the various literature. The Monoshock G/S & ST in some books are shown as 65 Nm (48 foot-pounds). For all the other monoshock (non-Paralever) models I use about 40 ftlbs. 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 retainer compound, this is NOT a solvent drying goo, instead it is a Loctite product, and need not be the exact type BMW specifies, IMO! Also, IMO, BMW uses such a product to avoid 'walking' of the surfaces. I have successfully used several types of Loctite bearing retainer compounds, and I prefer the slightly thicker ones....I think it applies and seals a bit better.
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.
The threaded ring that surrounds that input gear: 75+ foot-pounds, threads Hylomar'd.
Bevel drive pinion retaining nut, R80GS, R80R, R100GS, R100R: 150 foot-pounds
Cover housing, left side cover plate: 14 - 15 foot-pounds
Oil filler/level plug: 17 foot-pounds...I use somewhat less.
Oil drain plug: 17 foot-pounds...I use somewhat less.
Torque arm, front to frame: 32 foot-pounds
Torque arm, rear to housing: 25 foot-pounds
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):
Axle nut: 25 (35 maximum) foot-pounds. For the /5 and /6, I suggest using exactly 30 ftlbs.
Axle, late models, that use an allen bolt and not a nut: 25 foot-pounds
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, late R100RT, etc):
REAR WHEEL BOLTS.
Both three & four bolts/nuts are used on these various motorcycles. NEVER EVER oil NOR antiseize these threads; NEVER!....ONLY clean & dry threads. Use 63 foot-pounds for the R80ST, & a bit more, 77 ftlbs for the G/S & 1985+ models. Values for YOUR bike are in YOUR Rider's Handbook.
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 was the early original value range. I suggest you use 18 ftlbs. This applies to both the early hex head bolt and the later tapered allen head bolt.
For the carburetor band clamps, BMW DOES use screw type clamps, and moderately tight is correct.
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; or, 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 versions of clamps 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.
What is posted in this article above IS believed correct, but no guarantees as to that!
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
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.
02/29/2016: Add line to section 31/32...adding information on the side-bolt oil drain.
04/14/2016 : Begin to update article. Metacodes; format; horizontal lines; fonts & colors; layout....
08/21/2016: Minor correction to subframe mounting bolts in section 46.
© Copyright, 2014, R. Fleischer
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Last edit of THIS page: Sunday, August 21, 2016