BMW R models 1970-1985 Engine Technical specs
Engine | Type: | Air - cooled horizontally - opposed transverse twin, with pushrod operated overhead valves | ||
Dimensions | Bore | Stroke | Capacity - Actual | |
R45 | 70.0mm (2.76") | 61.5mm (2.42") | 473.1cc (28.86 cu in) | |
R50 | 67.0mm (2.64") | 70.6mm (2.78") | 497.6cc (30.35 cu in) | |
R60 | 73.5mm (2.89") | 70.6mm (2.78") | 598.8cc (36.53 cu in) | |
R65, R65LS | 82.0mm (3.23") | 61.5mm (2.42") | 649.2cc (39.60 cu in) | |
R75 | 82.0mm (3.23") | 70.6mm (2.78") | 745.3cc (45.46 cu in) | |
All 800cc models | 84.8mm (3.34") | 70.6mm (2.78") | 797.1cc (48.62 cu in) | |
R90/6, R90S | 90.0mm (3.54") | 70.6mm (2.78") | 897.8cc (54.77 cu in) | |
All 1000cc models | 94.0mm (3.70") | 70.6mm (2.78") | 979.4cc (59.74 cu in) | |
Compression ratio(standard values quoted, some machines may have been fitted with compression plates to reduce compression ratio from standard) | ||||
R45 | 9.2 : 1 | |||
R50 | 8.6 : 1 | |||
R60 | 9.2 : 1 | |||
R65, R65LS | 9.2 : 1 | |||
R75 | 9.0 : 1 | |||
R80/7 - 40 kw version | 9.2 : 1 | |||
R80/7 - 37 kw version, all other 800cc models | 8.2 : 1 | |||
R90/6 | 9.0 : 1 | |||
R90S | 9.5 : 1 | |||
R100/7 | 9.0 : 1 | |||
R100 (UK) | 8.2 : 1 | |||
All other 1000cc models* | 9.5 : 1 | |||
| ||||
Recommended engine speeds - rpm: | ||||
| Idle | Max. permissible continuous | Max. permissible | |
R45 R65 R65LS | 800 - 1100 | 7300 | 7650 | |
R50 R60/5 R60/6 R75/5 R75/6 R90/6 | 600 - 800 | 6500 | 7000 | |
R60/7 | 800 - 1100 | 6500 | 7200 | |
R75/7 | 800 - 1100 | 6500 | 7400 | |
All 800cc models | 800 - 1100 | 7200 | 7400 | |
R90S | 600 - 800 | 7000 | 7300 | |
R100/7 | 800 - 1100 | 6800 | 7400 | |
All other 1000cc models - UK - all R100T R100S 1977,78 - US - all except below | 800 - 1100 | 7000 | 7400 | |
All other 1000cc models - UK - all except those above - US - R100RS 1977 | 800 - 1100 | 7200 | 7400 | |
Claimed engine output - DIN: |
| Max. power (kw/hp @ rpm) | Max. torque (Nm/lbf ft @ rpm) | |
R45 | 26/35 @ 7250 | 37.4/27.6 @ 5500 | ||
R50 | 24/32 @ 6400 | 38.3/28.3 @ 5000 | ||
R60 | 29/40 @ 6400 | 48.1/35.5 @ 5000 | ||
R65 1978 - 80 models* | 33/45 @ 7250 | 50.0/36.9 @ 5500 | ||
R65 1981 on models, R65LS* | 37/50 @ 7250 | 52.3/38.6 @ 6500 | ||
R75 | 37/50 @ 6200 | 58.8/43.4 @ 5000 | ||
R80/7 - high comp. version | 40/55 @ 7000 | 62.5/46.1 @ 5500 | ||
R80/7 - low comp. version | 37/50 @ 7250 | 56.6/41.8 @ 5500 | ||
R80G/S R80ST* | 37/50 @ 6500 | 56.7/41.9 @ 5000 | ||
R80RT 1983, 84 models* | 37/50 @ 6500 | 59.0/43.5 @ 3500 | ||
R80, R80RT 85 on models* | 37/50 @ 6500 | 58.0/42.8 @ 4000 | ||
R90/6 | 44/60 @ 6500 | 73.0/53.9 @ 5500 | ||
R90S | 49/67 @ 7000 | 76.0/56.1 @ 5500 | ||
R100/7 | 44/60 @ 6500 | 73.5/54.2 @ 4000 | ||
R100T - US* | 44/60 @ 6500 | 74.6/55.1 @ 5500 | ||
R100T - UK, R100S - UK '77, '78 R100S - US, R100RS - US '78, '79, R100RT - US* | 48/65 @ 6600 | 75.0/55.4 @ 5500 | ||
R100 - UK | 49/67 @ 7000 | 72.0/53.1 @ 5500 | ||
R100S - UK '79, '80, R100RS - UK '77 - '80, R100RT - UK '79, '80 R100RS - US '77* | 51/70 @ 7250 | 76.0/56.1 @ 5500 | ||
R100CS R100RS R100RT - UK models '81 on* | 51/70 @ 7000 | 76.0/56.1 @ 6000 | ||
| ||||
Direction of engine rotation | clockwise, looking from front of machine | |||
Compression pressure | R80G/S R80ST R80RT R80 '85 on | All other models | ||
Good | over 9.0bar (131psi) | over 10.0bar (145psi) | ||
Normal | 7.5 - 9.0bar (109 - 131psi) | 8.5 - 10.0bar (123 - 145psi) | ||
Poor | below 7.5bar (109psi) | below 8.5bar (123psi) | ||
Valve clearances - engine cold | Normal | First 1000km (600m) | ||
Inlet | Exhaust | Inlet | Exhaust | |
/5,/6 | 0.15mm (.006") | 0.20mm (.008") | N/Av | N/Av |
/7, R80G/S, R80ST, R80RT '83 - 84 | 0.10mm (.004") | 0.15mm (.006") | 0.15mm (.006") | 0.20mm (.008") |
R45, R65, R65LS, R80, R80RT '85 on | 0.10mm (.004") | 0.20mm (.008") | 0.25mm (.010") | |
Valve timing | with 2.0mm (.08") valve clearance, tolerance of + - 2.5 degrees. | |||
R50/5 R60/5 R60/6 up to 1975 | R60/6 '76 R60/7 '77 | R60/7 '78 | ||
Inlet opens | 40 deg ATDC | TDC | 6 deg BTDC | |
Inlet closes | 40 deg ABDC | 40 deg ABDC | 34 deg ABDC | |
Exhaust opens | 40 deg BBDC | 40 deg BBDC | 46 deg BBDC | |
Exhaust closes | 40 deg BTDC | TDC | 6 deg BTDC | |
All R75 & R90, R100/7 R100S R100RS '77 | R80/7 R100/7 R100S R100RS '78 | All other models | ||
Inlet opens | 10 deg BTDC | 16 deg BTDC | 16 deg BTDC | |
Inlet closes | 50 deg ABDC | 44 deg ABDC | 44 deg ABDC | |
Exhaust opens | 50 deg BBDC | 56 deg BBDC | 56 deg BBDC | |
Exhaust closes | 10 deg BTDC | 4 deg BTDC | 4 deg ATDC | |
Valves | ||||
Head diameter: | Inlet | Exhaust | ||
R45 R50 | 34mm (1.34") | 32mm (1.26") | ||
R60 R65 up to '80 | 38mm (1.50") | 34mm (1.34") | ||
R65 '81 on, R65LS | 40mm (1.58") | 36mm (1.42") | ||
R75, all 800cc models | 42mm (1.65") | 38mm (1.50") | ||
R90/6 R90S R100/7 | 42mm (1.65") | 40mm (1.58") | ||
All other 1000cc models | 44mm (1.73") | 40mm (1.58") | ||
Head rim minimum thickness: | ||||
/5 /6 /7 | 1.0mm (0.0394") | 1.0mm (0.0394") | ||
R80G/S R80ST R80RT '83 - '84 | 0.8mm (0.0315") | 0.8mm (0.0315") | ||
R45 R65 R65LS | 1.0 - 1.5mm (0.0394 - 0.0591") | 1.0 - 1.2mm (0.0394 - 0.0472") | ||
Head maximum runout: | ||||
/5 /6 /7 | 0.025mm (0.0010") | 0.025mm (0.0010") | ||
R80G/S R80ST R80RT '83 - 84 | 0.020mm (0.0008") | 0.020mm (0.0008") | ||
Overall length: | ||||
R50/5 | 102.6 - 103.0mm | 102.1 - 102.5mm | ||
(4.0394 - 4.0551") | (4.0197 - 4.0354") | |||
R45 R65 R65LS | 98.8 - 100.2mm | 99.1 - 99.5mm | ||
(3.8898 - 3.9449") | (3.9016 - 3.9173") | |||
R60/5 R60/6 | 98.2 - 98.5mm | 97.2 - 97.5mm | ||
(3.8661 - 3.8780") | (3.8268 - 3.8386") | |||
R60/7 | 99.2 - 99.5mm | 98.2 - 98.5mm | ||
(3.9055 - 3.9173") | (3.8661 - 3.8780") | |||
All other models | 98.4 - 98.8mm | 98.4 - 98.8mm | ||
(3.8740 - 3.8898") | (3.8740 - 3.8898") | |||
Valve Guides | ||||
Length overall: | ||||
/5 /6 except R90S | 54mm (2.1260") | |||
R90S, /7 | 48mm (1.8898") | |||
R45 R65 R65LS | 45mm (1.7717") | |||
R80G/S R80ST R80RT '83 - '84 | 44mm (1.7323") | |||
Outside diameter: | ||||
/5 /6 /7 R80G/S R80ST R80RT '83 - 84 | 14.050 - 14.061mm (0.5532 - 0.5536") | |||
R45 R65 R65LS | 14mm (0.5512") | |||
Inside diameter: | ||||
/5 /6 /7 | 8mm (0.3150") | |||
R45 R65 R65LS | 7mm (0.2756") | |||
R80G/S R80ST R80RT '83 - 84 | 8.000 - 8.015mm (0.3150 - 0.3156") | |||
Bore in cylinder head: | ||||
/5 /6 /7 R45 R65 R65LS | 14mm (0.5512") | |||
R80G/S R80ST R80RT '83 - 84 | 14.000 - 14.018mm (0.5512 - 0.5519") | |||
Interference fit in cylinder head: | ||||
/5 /6 /7 | 0.032 - 0.061mm (0.0013 - 0.0024") | |||
All other models | N/Av | |||
Oversizes available | 0.1 & 0.2mm (0.004 & 0.008") | |||
Valve stem / guide standard clearance: | Inlet | Exhaust | ||
R50/5 | 0.040 - 0.070mm | 0.050 - 0.080mm | ||
(0.0016 - 0.0028") | (0.0020 - 0.0032") | |||
R45 R65 R65LS | 0.025 - 0.055mm | 0.040 - 0.070mm | ||
(0.0010 - 0.0022") | (0.0016 - 0.0028") | |||
R60 | 0.050 - 0.080mm | 0.065 - 0.095mm | ||
(0.0020 - 0.0032") | (0.0026 - 0.0037") | |||
All other models | 0.050 - 0.080mm | 0.050 - 0.080mm | ||
(0.0020 - 0.0032") | (0.0020 - 0.0032") | |||
Inlet and exhaust valve stem / guide max. permissible clearance - measured at top of guide: | ||||
R45 R65 R65LS | 0.10mm (0.0039") | |||
All other models | 0.15mm (0.0059") | |||
Valve seats | ||||
Outside diameter: | Inlet | Exhaust | ||
R50/5 | 36.175 - 36.200mm | 36.140 - 36.150mm | ||
(1.4242 - 1.4252") | (1.4228 - 1.4232") | |||
R45 | 36.2mm (1.4252") | 36.2mm (1.4252") | ||
R60 | 39.175 - 39.200mm | 39.175 - 39.200mm | ||
(1.5423 - 1.5433") | (1.5423 - 1.5433") | |||
R65 R65LS | 39.2mm (1.5433") | 39.2mm (1.5433") | ||
R75/5 | 43.175 - 43.200mm | 43.140 - 43.150mm | ||
(1.6998 - 1.7008") | (1.6984 - 1.6988") | |||
R75/6 R90/6 R90S | 43.175 - 43.200mm | 43.175 - 43.200mm | ||
(1.6998 - 1.7008") | (1.6998 - 1.7008") | |||
R75/7 R80/7 R100/7 | 43.175 - 43.200m | 43.134 - 43.200mm | ||
(1.6998 - 1.7008") | (1.6982 - 1.7008") | |||
R80G/S R80ST R80RT '83 - 84 | 43.175 - 43.200m | 43.134 - 43.150mm | ||
(1.6998 - 1.7008") | (1.6982 - 1.6988") | |||
All other 1000cc models | 45.175 - 45.200mm | 45.175 - 45.200mm | ||
(1.7785 - 1.7795") | (1.7785 - 1.7795") | |||
Bore in cylinder head - inlet and exhaust: | ||||
R50/5 | 36.00 - 36.025mm (1.4173 - 1.4183") | |||
R45 | 36mm (1.4173") | |||
R60 | 39.00 - 39.025mm (1.5354 - 1.5364") | |||
R65, R65LS | 39mm (1.5354") | |||
All 745cc 800cc 900cc, R100/7 | 43.000 - 43.025mm (1.6929 - 1.6939") | |||
All other 1000cc models | 45.000 - 45.025mm (1.7717 - 1.7727") | |||
Interference fit in cylinder head: | Inlet | Exhaust | ||
R50/5 R75/5 | 0.150 - 0.200mm (0.0059 - 0.0079") | 0.115 - 0.150mm (0.0045 - 0.0059") | ||
R45 R65 R65LS | N/Av | N/Av | ||
R75/7 R80/7 R100/7 R80G/S R80ST | ||||
R80RT '83 - '84 | 0.150 - 0.200mm (0.0059 - 0.0079") | 0.109 - 0.150mm (0.0043 - 0.0059") | ||
All other models | 0.150 - 0.200mm (0.0059 - 0.0079") | 0.150 - 0.200mm (0.0059 - 0.0079") | ||
Seat angle: | ||||
Main seating face | 45 deg | |||
At combustion chamber | 15 deg | |||
At inlet/exhaust port | 75 deg | |||
Seat width: | ||||
Inlet | 1.5mm (0.0591") | |||
Exhaust | 2.0mm (0.0787") | |||
Seat oversizes available | 0.2 0.4mm (0.0079 0.0168") | |||
Valve springs | ||||
Wire thickness | 4.25mm (0.1673") | |||
Spring free length - approx: | ||||
Blue or green code | 43.5mm (1.7126") | |||
Brown code | 46.0mm (1.811") | |||
Spring force at test length: | ||||
At 37.6mm (1.4803") | 27.84 - 30.16 kp (61.30 - 66.5 lb) | |||
At 28.5mm (1.1221") | 70.00 - 72.80 kp (154.30 - 160.5 lb) | |||
Rocker gear | ||||
Arm ID - /5 | 18.032 - 18.059mm (0.7099 - 0.7110") | |||
Bush OD - /5 | 18.012 - 18.030mm (0.7091 - 0.7098") | |||
Arm/bush clearance - /5 | 0.002 - 0.047mm (0.00008 - 0.00185") | |||
Bush ID /5 | 14.532 - 14.559mm (0.5721 - 0.5732") | |||
Shaft OD /5 | 14.512 - 14.530mm (0.5713 - 0.5720") | |||
Bush / shaft clearance /5 | 0.002 - 0.047mm (0.00008 - 0.00185") | |||
Arm axial float: | ||||
R80 R80RT 1985 | 0.03 - 0.07mm (0.0012 - 0.0028") | |||
All other models | Nil, but arm must be free to move | |||
Camshaft drive chain | ||||
Type: | ||||
/5 /6 /7 up to 1978 | Duplex roller chain | |||
All other models | Single row chain | |||
Size | 3/8 x 7/32" | |||
Number of links | 50 | |||
Camshaft | ||||
Front (alternator end) bearing bore | 40.000 - 40.039mm (1.5748 - 1.5763") | |||
Front flange bearing OD | 39.984 - 40.000mm (1.5742 - 1.5748") | |||
Front flange bearing ID | 25.000 - 25.013mm (0.9843 - 0.9848") | |||
Camshaft front bearing journal OD | 24.967 - 24.980mm (0.9830 - 0.9835") | |||
Camshaft radial clearance - at front bearing | 0.020 - 0.046mm (0.0008 - 0.0018") | |||
Rear (flywheel end) bearing bore | 24.000 - 24.021mm (0.9449 - 0.9457") | |||
Camshaft rear bearing journal OD | 23.967 - 23.980mm (0.9436 - 0.9441") | |||
Camshart radial clearance - at rear bearing | 0.020 - 0.054mm (0.0008 - 0.0021") | |||
Camshaft end float | 0.080 - 0.120mm (0.0032 - 0.0047") | |||
Base circle | 28mm (1.1024") | |||
Cam lift: | ||||
R50/5 R60 | 6.198mm (0.2440") | |||
All other models | 6.756mm (0.2660") | |||
Maximum permissible runout of ATU shaft - /5 /6 /7 up to '78 | 0.02mm (0.0008") | |||
Cam followers and pushrods | ||||
OD | 21.955 - 21.975mm (0.8644 - 0.8652") | |||
Crankcase ID | 21.985 - 22.006mm (0.8656 - 0.8664") | |||
Follower / crankcase clearance: | ||||
Standard | 0.010 - 0.051mm (0.0004 - 0.0020") | |||
Service limit | 0.075mm (0.0030") | |||
Pushrod length: | ||||
R45 R65 R65LS /5 /6 up to '75 | N/Av | |||
All other models | 274.7 - 275.3mm (10.8149 - 10.8386") | |||
Crankshaft and main bearings | ||||
Journal dimensions | Basically the same, but tolerances vary according to model and year. | |||
Main bearing bushes dimensions and radial clearances. | Selective fit depending on journal | |||
Main bearing journal/bush clearance: | ||||
R45 (UK), R65 (UK), R65LS (UK), all /5 /6 /7 | 0.035 - 0.065mm (0.0014 - 0.0025") | |||
/7 '81 on, R80G/S, R80ST, R65 (US), R65LS (US) - red size bush | 0.017 - 0.066mm (0.0007 - 0.0026") | |||
/7 '81 on, R80G/S, R80ST, R65 (US), R65LS (US) - blue size bush | 0.019 - 0.067mm (0.0008 - 0.0026") | |||
Crankshaft regrind stages: | ||||
1st | 0.25mm (0.0100") | |||
2nd | 0.50mm (0.0200") | |||
3rd | 0.75mm (0.0300") | |||
Max. runout - at front main bearing journal | 0.02mm (0.0008") | |||
Max. lateral runout at flywheel | 0.10mm (0.0008") | |||
Crankshaft standard endfloat | 0.08 - 0.15mm (0.0032 - 0.0059") | |||
Thrust washer thickness: | ||||
Standard - red | 2.483 - 2.530mm (0.0978 - 0.0996") | |||
Standard - blue | 2.530 - 2.578mm (0.0996 - 0.1015") | |||
Standard - green | 2.578 - 2.626mm (0.1015 - 0.1034") | |||
Standard - yellow | 2.626 - 2.673mm (0.1034 - 0.1052") | |||
Wear limit - all | minus 0.20mm (0.0079") | |||
Connecting rods and bearings | ||||
Crankpin standard OD | 47.975 - 47.991mm (1.8888 - 1.8894") | |||
Crankpin regrind stages: | ||||
1st | 0.25mm (0.0100") | |||
2nd | 0.50mm (0.0200") | |||
3rd | 0.75mm (0.0300") | |||
Connecting rod big - end ID - less bearing shells: | ||||
/5, /6, /7 1977 | 52.000 - 52.010mm (2.0472 - 2.0476") | |||
All other models | 52.000 - 52.015mm (2.0472 - 2.0478") | |||
Con. rod radial clearance | 0.023 - 0.069mm (0.0009 - 0.0027") | |||
Con. rod big - end width | 21.883 - 21.935mm (0.8615 - 0.8636") | |||
Crankpin width | 22.065 - 22.149mm (0.8657 - 0.8720") | |||
Con. rod axial clearance (endfloat): | ||||
Standard | 0.130 - 0.266mm (0.0051 - 0.105") | |||
Max. permissible | 0.320mm (0.0126") | |||
Max. weight difference between con. rods: | ||||
/5, /6 | 6 grams (0.2116 oz) | |||
/7, R45, R65, R65LS | 3 grams (0.1058 oz) | |||
R80G/S, R80ST | 2 grams (0.0705 oz) | |||
Con. rod small - end ID - less bush | 24.000 - 24.021mm (0.9449 - 0.9457") | |||
Small - end bush OD | 24.060 - 24.100mm (0.9472 - 0.9488") | |||
Small - end bush ID: | ||||
Standard | 22.015 - 22.020mm (0.8667 - 0.8669") | |||
Max. permissible | 22.040mm (0.8677") | |||
Gudgeon pin/small - end bush clearance: | ||||
/5,/6,/7 up to '80 - white coded pin | 0.015 - 0.023mm (0.0006 - 0.0009") | |||
/5,/6,/7 up to '80 - black coded pin | 0.018 - 0.026mm (0.0007 - 0.0010") | |||
/7 '81 on, R80G/S, R80ST | 0.015 - 0.024mm (0.0006 - 0.0009") | |||
R45, R65, R65LS | 0.015 - 0.025mm (0.0006 - 0.0009") | |||
Gudgeon pin OD: | ||||
/5,/6,/7 up to '80 - white coded pin | 21.997 - 22.000mm (0.8660 - 0.8661") | |||
/5,/6,/7 up to '80 - black coded pin | 21.994 - 21.997mm (0.8659 - 0.8660") | |||
/7 '81 on, R80G/S, R80ST | 21.996 - 22.000mm (0.8659 - 0.8661") | |||
R45, R65, R65LS | 21.995 - 22.000mm (0.8659 - 0.8661") | |||
Gudgeon pin bore ID - in piston: | ||||
/5,/6,/7 up to '80 - white code (W stamped in piston crown) | 22.000 - 22.003mm (0.8661 - 0.8662") | |||
/5,/6,/7 up to '80 - black code (S stamped in piston crown) | 21.997 - 22.000mm (0.8660 - 0.8661") | |||
/7 '81 on, R80G/S, R80ST | 22.000 - 22.004mm (0.8661 - 0.8663") | |||
R45 | 22.002 - 22.007mm (0.8662 - 0.8664") | |||
R65, R65LS | 22.005 - 22.010mm (0.8663 - 0.8665") | |||
Gudgeon pin/piston clearance: | ||||
/5,/6,/7 up to '80 | 0.000 - 0.006mm (0.0000 - 0.0002") | |||
/7 '81 on, R80G/S, R80ST | 0.000 - 0.008mm (0.0000 - 0.0003") | |||
R45 | 0.002 - 0.012mm (0.0001 - 0.0005") | |||
R65, R65LS | 0.005 - 0.015mm (0.0002 - 0.0006") | |||
Cylinders | ||||
Type: | ||||
All models up to 1980 finned jacket by 'Al-Fin' process | Cast iron sleeve joined to aluminium alloy | |||
R45, R65, R65LS '81 on | Aluminium alloy barrel with 'Nikasil' plated bore | |||
1000cc and 800cc, '81 on | Aluminium alloy barrel with 'Galnikal' plated bore | |||
Cylinder standard bore ID - at specified bore size code: | ||||
A | B | C | ||
R50/5 | 67.000mm | 67.010mm | 67.020mm | |
(2.7368") | (2.6382") | (2.6386") | ||
R45 | 69.995 - 70.005mm | 70.005 - 70.015mm | 70.015 - 70.025mm | |
(2.7557 - 2.7561") (2.7561 - 2.7565") (2.7565 - 2.7569") | ||||
R60/5, R60/6 | 73.500mm | 73.510mm | 73.520mm | |
(2.8937") | (2.8941") | (2.8945") | ||
R60/7 | 73.500 - 73.510mm | 73.510 - 73.520mm | 73.520 - 73.530mm | |
(2.8937 - 2.8941") (2.8941 - 2.8945") (2.8945 - 2.8949") | ||||
R65, R65LS | 81.995 - 82.005mm | 82.005 - 82.015mm | 82.015 - 82.025mm | |
(3.2281 - 3.2285") (3.2285 - 3.2289") (3.2289 - 3.2293") | ||||
R75/5, R75/6 | 82.000mm (3.2283") | 82.010mm (3.2287") | 82.020mm (3.2291") | |
R75/7 | 82.005 - 82.015mm (3.2285 - 3.2289") | 82.015 - 82.025mm (3.2289 - 3.2293") | 82.025 - 82.035mm (3.2293 - 3.2297") | |
All 800cc models | 84.795 - 84.805mm (3.3384 - 3.3388") | 84.805 - 84.815mm (3.3388 - 3.3392") | 84.815 - 84.825mm (3.3392 - 3.3396") | |
R90/6, R90S | 90.000mm (3.5433") | 90.010mm (3.5437") | 90.020mm (3.5441") | |
All 1000cc models | 94.005 - 94.015mm (3.7010 - 3.7014") | 94.015 - 94.025mm (3.7014 - 3.7018") | 94.025 - 94.035mm (3.7018 - 3.7022") | |
Rebore sizes: | ||||
/5,/6, R60/7, R75/7 - 1st | 0.50mm (0.020") | |||
/5,/6, R60/7, R75/7 - 2nd | 1.00mm (0.040") | |||
R45 & R65 to '80, R80/7 - 1st | 0.25mm (0.010") | |||
R45 & R65 to '80, R80/7 - 2nd | 0.50mm (0.020") | |||
All 1000cc models to '80 | 0.25mm (0.010") | |||
All models '81 on | rebores not possible, pistons and cylinders must be renewed when excessively worn | |||
Maximum ovality: | ||||
R45, R65, R65LS | 0.005mm (0.0002") | |||
R80G/S, R80ST - 20mm (0.8") from top of bore | 0.005mm (0.0002") | |||
R80G/S, R80ST - 115mm (4.5") from top of bore | 0.010mm (0.0004") | |||
All other models | 0.010mm (0.0004") | |||
Maximum taper: | ||||
/5,/6 | 0.010mm (0.0004") | |||
All other models | 0.020mm (0.0008") | |||
Pistons | ||||
Standard OD - at specified size code: | ||||
| A | B | C | |
R50/5 | 66.960mm (2.6362") | 66.970mm (2.6366") | 66.980mm (2.6370") | |
R45 | 69.955 - 69.965mm (2.7541 - 2.7545") | 69.965 - 69.975mm (2.7545 - 2.7549") | 69.975 - 69.985mm (2.7549 - 2.7553") | |
R60/5, R60/6 | 73.460mm (2.8921") | 73.470mm (2.8925") | 73.480mm (2.8929") | |
R60/7 | 73.470mm (2.8925") | 73.480mm (2.8929") | 73.490mm (2.8933") | |
R65, R65LS | 81.955 - 81.965mm (3.2266 - 3.2270") | 81.965 - 81.975mm (3.2270 - 3.2274") | 81.975 - 81.985mm (3.2274 - 3.2278") | |
R75/5, R75/6 | 81.960mm (3.2268") | 81.970mm (3.2272") | 81.980mm (3.2276") | |
R75/7 | 81.965mm (3.2270") | 81.975mm (3.2274") | 81.985mm (3.2278") | |
All 800cc models | 84.765mm (3.3372") | 84.775mm (3.3376") | 84.785mm (3.3380") | |
R90/6, R90S | 89.960mm (3.5417") | 89.970mm (3.5421") | 89.980mm (3.5425") | |
All 1000cc models | 93.960mm (3.6992") | 93.970mm (3.6996") | 93.980mm (3.7000") | |
Standard piston/cylinder clearance: | ||||
/5,/6 | 0.035 - 0.045mm (0.0014 - 0.0018") | |||
R60/7 | 0.020 - 0.040mm (0.0008 - 0.0016") | |||
R75/7 | 0.019 - 0.041mm (0.0007 - 0.0016") | |||
R80/7 | 0.023 - 0.047mm (0.0009 - 0.0029") | |||
R45 & R65 up to '80 | 0.030 - 0.050mm (0.0012 - 0.0020") | |||
All 1000cc models up to '80 | 0.028 - 0.052mm (0.0011 - 0.0021") | |||
All models '81 on | 0.030 - 0.040mm (0.0012 - 0.0016") | |||
Maximum permissible piston/cylinder clearance: | ||||
/5,/6 | 0.120mm (0.0047") | |||
All other models | 0.080mm (0.0032") | |||
Piston weight group | + or - stamped in piston crown - both | |||
Pistons must be of the same weight group, i.e. carry the same marking. | ||||
Piston rings | ||||
Top: | ||||
Type | Plain, rectangular section | |||
Thickness: | ||||
/5,/6 | 1.790 - 1.810mm (0.705 - 0.0713") | |||
R45 | 1.478 - 1.490mm (0.582 - 0.0587") | |||
All other models | 1.728 - 1.740mm (0.0680 - 0.0685") | |||
End gap - installed: | ||||
R50, R60 | 0.25 - 0.40mm (0.0098 - 0.0158") | |||
R45 | 0.25 - 0.45mm (0.0098 - 0.0177") | |||
R75/5, R75/6, R90/6, R90S | 0.30 - 0.45mm (0.0118 - 0.0177") | |||
/7 '81 on | 0.40 - 0.65mm (0.0158 - 0.0256") | |||
All other models | 0.30 - 0.50mm (0.0118 - 0.0197") | |||
Side clearance: | ||||
/5,/6 | 0.060 - 0.070mm (0.0024 - 0.0028") | |||
/7 | 0.060 - 0.090mm (0.0024 - 0.0035") | |||
All other models | 0.050 - 0.082mm (0.0020 - 0.0032") | |||
Second: | ||||
Type | Plain, with stepped or tapered face | |||
Thickness | ||||
/5,/6 | 2.030 - 2.050mm (0.0799 - 0.0807") | |||
/7, R45 up to '80 | 2.010 - 2.022mm (0.0791 - 0.0796") | |||
All other models | 1.978 - 1.990mm (0.0779 - 0.0784") | |||
End gap - installed: | ||||
R50, R60 | 0.25 - 0.40mm (0.0098 - 0.0158") | |||
R45 | 0.25 - 0.45mm (0.0098 - 0.0177") | |||
R80G/S, R80ST | 0.30 - 0.50mm (0.0118 - 0.0197") | |||
/7 '81 on | 0.40 - 0.65mm (0.0158 - 0.0256") | |||
All other models | 0.30 - 0.45mm (0.0118 - 0.0177") | |||
Side clearance: | ||||
/5,/6 | 0.050 - 0.060mm (0.0020 - 0.0024") | |||
All other models | 0.040 - 0.072mm (0.0016 - 0.0028") | |||
Oil scraper: | ||||
Type | One piece | |||
Thickness: | ||||
/5,/6 | 4.010 - 4.030mm (0.1579 - 0.1587") | |||
/7 | 4.010 - 4.022mm (0.1579 - 0.1584") | |||
R80G/S, R80ST, R45 '81 on | 3.478 - 3.490mm (0.1369 - 0.1374") | |||
R45 up to '80 | 3.510 - 3.522mm (0.1382 - 0.1387") | |||
R65, R65LS | 3.978 - 3.990mm (0.1566 - 0.1571") | |||
End gap - installed: | ||||
R50/5, R60/5 | 0.20 - 0.35mm (0.0079 - 0.0138") | |||
R60/6, R60/7 | 0.25 - 0.35mm (0.0098 - 0.0138") | |||
R45 | 0.25 - 0.45mm (0.0098 - 0.0177") | |||
All other models | 0.25 - 0.40mm (0.0098 - 0.0158") | |||
Side clearance: | ||||
/5,/6 | 0.030 - 0.040mm (0.0012 - 0.0016") | |||
R60/7 | 0.020 - 0.050mm (0.0008 - 0.0020") | |||
All other models | 0.030 - 0.062mm (0.0012 - 0.0024") | |||
Torque wrench settings | ||||
Component: | Nm | lb/ft | ||
Rocker cover cap nut - R8, R80RT '85 on | 20 | 15 | ||
Spark plugs | 20 - 30 | 15 - 22 | ||
Valve adjuster locknuts | 18 - 23 | 13.5 - 17 | ||
Cylinder head retaining nuts - all models up to '80: | ||||
1st stage | 15 | 11 | ||
2nd stage | 35 | 26 | ||
3rd stage | 40 | 29.5 | ||
Standard setting | 38 - 42 | 28 - 31 | ||
Cylinder head retaining nuts - all models '81 on: | ||||
1st stage | 15 | 11 | ||
2nd stage | 25 | 18.5 | ||
3rd stage | 35 | 26 | ||
Standard setting | 35 - 39 | 26 - 29 | ||
Exhaust pipe finned nuts: | ||||
R80, R80RT '85 on | 160 | 118 | ||
R45 & R65 '79 - '80,/7 up to '80 | 140 - 180 | 103 - 133 | ||
All other models | 200 - 220 | 148 - 162 | ||
Connecting rod bolts | 48 - 52 | 35.5 - 38 | ||
Flywheel mounting bolts: | ||||
/5 | 58 - 62 | 43 - 46 | ||
R60/6 & R75/6 up to 9/74 - 10mm bolts | 60 - 65 | 44 - 48 | ||
R90/6 & R90S up to 9/74 - 10mm bolts | 70 - 75 | 52 - 55 | ||
/6 '75 on and all other models - 11mm bolts | 100 - 105 | 74 - 77.5 | ||
Oil pump pickup mounting bolts | 9 | 6.5 | ||
Camshaft flange bearing - all models '79 on | 15 - 18 | 11 - 13.5 | ||
Sump mounting bolts | 9 - 12 | 6.5 - 9 | ||
Alternator rotor retaining bolt | 23 - 27 | 17 - 20 | ||
Starter motor mounting bolts | 47.5 | 35 | ||
ATU retaining nut: | ||||
/5,/6 | 6 - 7 | 4.5 - 5 | ||
/7 up to '78 | 5 - 6 | 4 - 4.5 | ||
All other models | N/App | N/App | ||
Oil filter inner cover retaining bolt - /5,/6 only | 41 | 30 | ||
Engine oil drain plug: | ||||
Models up to '80 | N/Av | N/Av | ||
All models '81 on | 41 | 30 | ||
Oil filter cover mounting bolts | 10 | 7.5 | ||
Engine mounting nuts: | ||||
R80, R80RT '85 on | 54.2 | 40 | ||
All other models | 70 - 77 | 52 - 57 | ||
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