Torque Specifications

Every number in this chapter is a compromise between two failures. Too little and the joint works loose under vibration that never stops; too much and you stretch a stud, pull a thread out of the forty-year-old aluminium crankcase the long cylinder studs are threaded into, or warp a head that was flat when you started. BMW published figures for all of it. Some of those figures are wrong.

That is not a slur — it is documented. In March 1982 BMW issued a service bulletin telling its own dealers to stop trusting the foot-pound conversions printed in the workshop manuals, because they contained errors. Those errors were copied forward into Clymer and Haynes, and they are still being quoted in forum threads today. Convert from Newton-metres yourself, every time.

Where this reference disagrees with the factory book, it says so and explains why. The values marked with a warning are the ones airheads do not forgive.

Every figure on this page resolves to one model and year in the book. Pick your bike and the rows that apply to it come forward, with the rest marked.

Open this chapter in the book

11 · Engine

Component	ft-lb	Nm	Prep	Applies	Notes
Cylinder head / stud nuts (6) — BMW factory	25.8–28.8	35–39	Non-lubricated or oiled	/7 range, documented	BMW-WSM7 In three stages: 15 → 35 → 39 N·m, cross-pattern. This is what the workshop manual prints, identically on the 12.77 and 11.78 sheets. Earlier revisions of this guide published 25 ft-lb / 34 N·m and told you never to exceed 26 — that is below BMW's own minimum, and the instruction to stay under 26 contradicted the factory manual. Corrected. Rocker studs oily; re-oil if squeaking.
Connecting rod bolts	35.4–38.4	48–52	—	/7 range · factory	BMW-WSM7 Factory figure, 12.77 and 11.78 sheets.
Oil sump at crankcase	6.6–8.1	9–11	—	/7 range · factory	BMW-WSM7 Low, and into aluminium — a common place to strip threads with a big wrench.
Carburettor threaded stub pipe	8.8 + 1.5	12 + 2	—	/7 range · factory	BMW-WSM7 Into the head. Gentle.
Cylinder head / stud nuts — the specialist deviation	25	34	shop practice, not factory	high-mileage engines	Snowbum holds 25 ft-lb for all models and warns against anything above ~26, on the grounds that these studs thread into a fifty-year-old aluminium crankcase that may already have been over-torqued by someone else. That is a considered position about aged hardware, not a reading of the factory figure — and it is a deliberate 4 N·m below BMW's minimum. Both numbers are published here because the choice is yours to make knowingly: the factory value on a known-good crankcase, the conservative value if the thread history is unknown. What you must not do is take 25 as the factory spec, which is what this guide previously implied.
Rocker adjuster lock nut	13.3–17.0	18–23	—	All · factory	BMW-WSM7 BMW prints “nuts for valve adjustment screw 18…23 N·m”. The 18–22 this guide carried was very close; the range is corrected to the factory one. 12 ft-lb is acceptable shop practice and gentler on threads.
Valve cover acorn nut	14	19	New washer	All	Don't run to full spec. Check stud thread engagement near plug.
Auto-advance M6 nut (cam tip)	4 MAX (48 in-lb)	5.4	New wave washer	thru '78	Snaps the cam tip. Start 24–30 in-lb, tiny wrench, by feel.
Engine to frame	55	75	—	All
Crankshaft rod bolts	36	49	NEW bolts, oiled	All except R80GS/R80R/R100GS/R100R	Always new. Tri-tool needed. Applies to twin-shock and monolever (R80, R80RT, R65 etc.), not just twin-shock.
Crankshaft rod bolts	15 + 40°	20 + 40°	NEW bolts, oiled	R80GS · R80R · R100GS · R100R	Torque-angle method — not a plain torque figure. Do not substitute 36 ft-lb.
Crank front bearing carrier	17	23	—	All
Flywheel on crankshaft (5 × 11 mm)	73.7–77.4	100–105	Faint oil	1975+ · factory	BMW-WSM7 Factory figure, printed identically on the 12.77 and 11.78 sheets. Neither number in circulation was right: this guide previously published 102–108 N·m (top end 3 N·m high) and the widely-seen “100 ± 5” runs 5 N·m low at the bottom. The ’81+ bulletin claim of 90 ft-lb / 125 N·m oiled and reusable appears nowhere in this manual, whose latest bound-in sheet is 3.82 — treat it as unverified until the bulletin itself is read. 10 mm bolts: ’73− = 42–45, 1974 = 52–55 (the 1974 10 mm bolts are the ones with a shearing reputation — 1975 went to 11 mm).
Clutch bolts (6)	14.5–16	20–22	Blue Loctite, new star washers	'80/81+ carrier clutch	/5 = 14 · /6–/7 thru '80 = 16–17 (the 1978 factory chart says 7.5 — see Sources & Conflicts).
Clutch bolts (6) — small airhead	7.3 (88 in-lb)	10	Blue Loctite, new star washers	R45 / R65, old-style clutch	Roughly half the large-airhead figure. Using the 14.5–16 row here is ~2× spec.
Oil pan drain plug	20–22	27–30	New washer	All	Use low side.
Oil pan bolts	5.5–6 (66–72 in-lb)	7.5–8	Dry, no sealant	All	Cross-pattern centre-out, staged, inch-lb wrench. Book 6.5–8.5 is high.
Oil pickup bolts	6.5	9	Blue Loctite	All
Oil pump cover	7.3 (88 in-lb)	10	Blue Loctite	All	Replace Phillips-screw covers with updated version.
Oil filter outer cover (3)	60–71 in-lb	6.8–8	Star/wave washers	Cooler models	Spec 10 Nm is high. Staged, even.
Oil filter inner cap bolt	15	20	New washer	Early bikes, no oil cooler	Haynes shows 41 N·m / 30 ft-lb for /5–/6; Snowbum calls that vastly too high. 20 N·m is the working figure.
Oil cooler banjo nuts (17 mm)	13 (14.5 MAX)	18	4 NEW washers	Cooler models	Hold banjo body; re-check after 2 h+.
Cam flange / front main brg	11–13	15–18	—	All ('85+ = 18)
Timing chain cover	62–71 in-lb	7–8	—	All	Staged, alternating.

12 · Engine Electrics

Component	ft-lb	Nm	Prep	Applies	Notes
Spark plugs — BMW factory, 12.77 sheet	17.0–22.1	23–30	dry threads	/7 range	BMW-WSM7 BMW then lowered it — see the row below. The “25 N·m ±3” this guide used to print is not a figure BMW published for these machines.
Spark plugs — BMW factory, '79 and 1981 sheets	14.7 + 3.7	20 + 5	dry threads	'79 onward	BMW-WSM7 20–25 N·m — the later factory figure, printed identically on the 11.78 and 3.82 sheets. Alloy head; go by feel rather than chasing the top. Note where this leaves the shop practice below: 13.5–15 ft-lb with anti-seize sits just under BMW's own dry minimum of 14.7, which is about what you would expect once the thread is lubricated.
Spark plugs — with anti-seize (not factory)	13.5–15	18–20	shop practice	All	Anti-seize lubricates the thread, so the same wrench reading produces materially more clamp load. Shops that use it reduce the torque by roughly a quarter, and the figures here are that practice — BMW does not specify anti-seize on the plug thread and publishes no reduced value for it. Use one condition or the other; do not mix a dry torque with a lubricated thread.
Starter motor bolts	35	47	—	All	Published spec likely excessive; seat starter squarely first.
Alternator rotor bolt	14 MAX	19	Taper spotless	All	Book 16.6–19.5. Taper fit — clean, nick-free, no gasoline.

18 · Exhaust

Component	ft-lb	Nm	Prep	Applies	Notes
Exhaust finned nuts	118	160	Hi-temp anti-seize YEARLY	All	Lit shows up to 159 ft-lb from bad conversions — 160 Nm is the real figure. If seized: penetrant + heat, or cut the nut, never force the port threads.

21–23 · Clutch & Transmission

Component	ft-lb	Nm	Prep	Applies	Notes
Trans drain / fill plugs	14–18.5 / 20–22	19–25 / 27–30	New washers	All	Low side of both. Fill to the bottom of the filler threads with the bike on the centre stand — not leaned, not on a lift.
Transmission to engine — early	14–16.5	19–22	Anti-seize the studs	/5 · /6 · early /7	Canonical row lives in Transmission & Final Drive; this is the same value.
Transmission to engine — /7 and 1981+	24	33	—	/7 and 1981+	The single “20 N·m for all” row this table used to carry conflicted with the chapter figure. Both values are now stated once, split at the same breakpoint. R45/R65 factory data is not verified here — check the 248-series manual.
Shift lever central bolt	5 (60 in-lb)	6.8	—	All	M6 × 80, 5 mm allen. The "13 ft-lb" in books is a confusion.
Output flange → U-joint (4)	25–29	34–39	Blue Loctite, NO lockwashers	All	Short bolts only. Adapter tool at 90°.
Output flange centre nut	148–173	201–235	Taper clean & dry	All	160 works. No gasoline on tapers.
Selector fork / cam bracket	18 ('81+: 14)	24 / 19	—	by year

26 · Driveshaft & Swing Arm

Component	ft-lb	Nm	Prep	Applies	Notes
U-joint bolts (4)	25–26 (29 MAX)	34–39	Dry + drop of Blue Loctite	All	NEVER lockwashers — they crack, bolts loosen, trans case dies. R100GS = 29.
Driveshaft coupling nut	150–180	203–244	—	All
Swing arm pivot pins	preload 15 → 7.5–9	20 → 10–12	—	Twin-shock	Equalise side gaps within ~0.02".
Swing arm 27 mm locknuts	74–88	100 + 20	—	Twin-shock · 3.82	BMW-RA382 Factory 3.82: 100+20 N·m, and the pivot pins themselves are set to a 10+2 N·m preload first — a two-stage procedure this guide did not previously mention. Modified thin-wall socket.
Driveshaft drain / fill	10	14	New washer	All	Located on rear-drive nose.

31–32 · Forks & Steering

Component	ft-lb	Nm	Prep	Applies	Notes
Top crown / centring nut	88–96	120–130	—	twin-shock large twins	BMW-WSM7 §31/§32 Factory: cap nut for telescopic fork 120–130 N·m (12.77 and ’79 sheets); 1981 sheet: 120 N·m (88), and the slotted adjusting nut beneath it is set to zero play, never to a torque. Steering-bearing friction 350 ±20 Ncm. Bearing preload road check: bars fall left on the centre stand. NOT VERIFIED for R45/R65 or the later GS / R100R front ends.
Fork tube top nuts	80	108	—	All
Fork drain (bottom nut)	~17	23	New wave washer	thru '80	Side-bolt type on late models: 6 MAX.
M8×1 damper nut	15–17 ('81+: 25)	20–23 / 34	—	by year
Slider base screw (bottom of leg)	59–74	80–100	—	’79 on	BMW-WSM7 §31 ’79 sheet. Holds the damper assembly into the slider.
Damper retaining bolt in slider	26	35	—	1981-on fork	BMW-WSM7 §31 1981 sheet.
Fork oil drain / filling plugs	5.9 / 6.6	8 / 9	—	1981-on fork	BMW-WSM7 §31 1981 sheet. Small threads into castings — gentle.
End plug, damper tube · spring support top	18.4	25	—	’79 on	BMW-WSM7 §31 ’79 sheet.
Lower fork bridge clamp bolts	26–29	35–40	—	large twins	BMW-WSM7 §31 ’79 sheet: 35–40 N·m; 1981 sheet: 40 N·m (29). The flat 25 ft-lb previously here sat just under the factory band.
Handlebar nuts	15	20	—	All

33 · Rear Drive & Shocks

Component	ft-lb	Nm	Prep	Applies	Notes
Rear drive → driveshaft housing (4)	35	47	Paper gasket, dry	Twin-shock	BMW-WSM7 §33 1981 sheet: “twelve-sided nut for final drive housing / swinging fork mounting, 47 N·m (35)” — the 12.77 sheet’s lower “nuts on drive housing” line is the cover nuts (18 N·m), a different fastener. Mono models: no gasket, Loctite retainer instead.
Shock mounts	25	34	Grease bushings	All twin-shock
Shock mount — monolever	34	46	Grease bushings	Monolever pre-1987	From 1987 the figure drops to 21 ±3 ft-lb (28 ±4 N·m) — a materially different number on the same bolt.
Shock mount — monolever	21 ±3	28 ±4	Grease bushings	Monolever 1987+
Shock mount — paralever	19	26	Grease bushings	Paralever
Paralever pivot pins	11 → back off → 5.5	15 → back off → 7.5	Clean threads	Paralever	Set 15 N·m, back off, re-set 7.5 N·m. Locknuts 75–80 ft-lb. LH pivot stub 80 ft-lb. RH pivot shaft 3.5 ft-lb with lock nut 77 — the low figure is not a typo.
Input pinion nut	122	165	Blue Loctite	after /6 · 3.82 · except GS/R below	BMW-WSM7 §33 Now page-verified: the 12.77 sheet prints 150 +15 N·m (111 +11); the 1981 sheet prints 165 N·m (122), and the R45/R65 book (5.82) the same 165. The 149–156 figure this guide used to carry traces to earlier print. Known trouble spot — always Loctite. /5–/6: 75 ft-lb.
Input pinion nut	150	203	Blue Loctite	R80GS · R80R · R100GS · R100R	Materially higher than the 165 N·m used on the twin-shocks, and both are right. The 3.82 Reparaturanleitung predates the GS and Paralever, so its 165 N·m does not cover them — this figure comes from the later literature for those models. Same known trouble spot; always Loctite.
Rear drive drain / fill	17 / 15 max	23 / 20	New washers	All
Rear drive oil-level inspection plug	7.4	10	New washer	’81+ twin-shock, mono, paralever	BMW-WSM7 §33 1981 sheet: level check screw 10 N·m (7.4 ft-lb). This guide previously capped it at 5.5 ft-lb as shop caution; the factory figure is a touch higher — but this is still the plug that gets stripped because people reach for the 17 ft-lb drain figure above it. Approach the number, don’t attack it.
Rear drive → driveshaft housing	48	65	Loctite retainer, no gasket	R80G/S · R80ST	Other monoshock models ~40 N·m / 30 ft-lb.
Torque arm front / rear	32 / 25	43 / 34	—	All

34 · Brakes

Component	ft-lb	Nm	Prep	Applies	Notes
Brembo caliper mounts	22–23	30–31	—	Brembo / fixed ATE	ST/GS: 26.
Brake lines / banjos — hose banjo bolt	6–7	8–9.5	New sealing washers, every time	banjo unions only	'81+ book allows 11 N·m — too high for these threads. Gentle, and stop at the first sign of the washer crushing out. This row covers the hose-to-caliper / hose-to-master banjo bolt only. Rigid pipe-to-master and pipe-to-caliper flare unions, and the later brake systems, are different connections with their own figures — the single “All” value this table used to carry conflated all of them. Take the number for the exact joint from the manual for that brake generation.
Brake pipe → brake hose union	8.8 +2.2	12 +3	—	1981-on	BMW-WSM7 §34 1981 sheet, printed as a range starting at the nominal.
Brake pipe → master cylinder · pipe → caliper	5.9 +1.5	8 +2	—	flare unions	BMW-WSM7 §34 12.77 and ’79 sheets: 8 +3 N·m; 1981 sheet: 8 +2. Rigid-pipe flare nuts — not the hose banjo above.
ATE swinging caliper — bottom plugs (end caps)	29.5–33.2	40–45	—	ATE swinging, 1974–1980	BMW-WSM7 §34 Factory “end cap” 40–45 N·m, printed identically on the 12.77 and ’79 sheets. The widely-circulated “43–47 ft-lb” matches the factory figure only if read as N·m — a units mix-up in the secondary sources this guide previously followed. At an actual 43–47 ft-lb you are 40% over.
Disc mounting bolts	17	23	—	All (GS/R: 24)

36 · Wheels & Axles

Component	ft-lb	Nm	Prep	Applies	Notes
Axle nut	35	48	Light grease on axle	large twins — see note	BMW-WSM7 §36 Factory, by sheet: 12.77 and ’79 print 45–50 N·m (33.2–36.8 ft-lb) for the quick-release axle front and rear; the 1981 sheet prints 48 N·m (35 ft-lb). Wheel-bearing friction check at this torque: 15–30 Ncm. The 25 ft-lb this guide carried earlier traced to secondary tables and is withdrawn. NOT VERIFIED for R45/R65 — the small twins use different axle hardware; use the 248-series book.
Axle pinch bolts	11 ±1.5 (’81+: 12.5)	15 ±2 / 17	New wave washers	by year	BMW-WSM7 §31/§36 ’79 sheet: 15 ±2 N·m. 1981 sheet: 17 N·m (12.5). The step up came with the 1981 fork, not in ’84 as previously printed here.
REAR WHEEL bolts — Mono/Paralever	63 ST · 77 GS/'85+	85 / 104	CLEAN & DRY ONLY	Mono / Para	Never oil or anti-seize — wheel can depart the bike. Scrub off any found.

46 · Frame

Component	ft-lb	Nm	Prep	Applies	Notes
Centre stand	32–35	43–48	—	/5–’84 twin-shock	BMW-WSM7 §46 Factory 12.77: centre-stand securing bolts 43–48 N·m (32–35 ft-lb). The 25–26 ft-lb previously printed here traced to secondary tables and was about 25% low — these bolts loosen, and a stand that drops at speed is not a small failure. The ’85+ monolever figure remains unverified here.
Side stand pin	13	18	—	'81+
Rear subframe bolts	18	24	—	All	Hex or later tapered allen head.

Torque Specifications

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