Identification
Parts that are different for each version are listed here.
10 versions have 10 quantity columns. The quantity is
0 if the part is never on that version.
1 if the part is always on that version.
1 if the part is sometimes on that version.
E N G I N E V E R S I O N S
01010 12345 67890 Engines ’74-75 6 volt
52341 00010 00000 engine #4 variator 25 mph
01010 12345 67890 Engines ’76-77 6 volt
53444 10000 00000 engine #1 Dimoby 20 mph
53949 01000 00000 engine #2 Dimoby 25 mph
53744 00100 00000 engine #3 Dimoby 30 mph
52341 00010 00000 engine #4 variator 25 mph
53745 00001 00000 engine #5 variator 30 mph
01010 12345 67890 Engines ’78-80 12 volt
54146 00000 10000 engine #6 Dimoby 20 mph
54147 00000 01000 engine #7 Dimoby 25 mph
54149 00000 00100 engine #8 Dimoby 30 mph
54148 00000 00010 engine #9 variator 25 mph
54844 00000 00001 engine #0 variator 30 mph
01010 12345 67890 Cylinders
22335 00100 00000 cyl. says 581051, FB2 47
23460 00001 01111 cyl. says 682051, most say nothing
53505 10000 10000 cyl. says 681051, TUM207
54328 01010 00000 cyl. S25682051, TUM207
01010 12345 67890 Exhausts
21103 11100 00000 exhaust
22872 11111 11111 exhaust
01010 12345 67890 Intakes
16673 00010 00010 intake center ∅16 x 10
16619 00001 00000 intake center ∅17 x 12
21201 01100 01100 intake side ∅19 x 12
22899 00001 00001 intake side ∅19 x 13?
53496 10000 10000 intake side ∅19 x 10
01010 12345 67890 Intake Gaskets
52646 10000 10000 intake gasket round hole
17073 01111 01111 intake gasket rectangle hole
01010 12345 67890 Carburetors
20026 00001 00000 carb AR2-12-705 center ∅17
22160 01100 00000 carb AR2-12-729 side-5 ∅19
22160 00000 01100 carb AR2-12-729 side-6 ∅19
52175 00010 00000 carb AR2-10-737 center ∅16
52175 00010 00000 carb AR2-10-759 center ∅16
52175 00000 00010 carb AR2-10-991 center ∅16
54115 10000 00000 carb AR2-10-910 side-5 ∅19
54115 00000 10000 carb AR2-10-910 side-6 ∅19
54973 00001 00000 carb AR2-12-873 side-5 ∅19
54973 00000 00001 carb AR2-12-873 side-6 ∅19
54973 00000 00001 carb AR2-12-978 side-6 ∅19
01010 12345 67890 Model 50, 50V Chains
18368 10000 10000 chain 99L+1 for 12 x 48T
17693 01000 01000 chain 96L+1 for 11 x 44T
18427 00100 00100 chain 97L+1 for 13 x 44T
17785 00011 00011 chain 102L+1 for 11 x 54T
01010 12345 67890 Model 40 Chains
18429 10000 10000 chain 93L+1 for 12 x 48T
20766 01000 01000 chain 90L+1 for 11 x 44T
53874 00100 00100 chain 91L+1 for 13 x 44T
AV7 Dc and AV7 Vc Engine Parts
# part# qty price description 1. Gaskets, bolts
02 18568 1 $15.0 case bolt set 2 #2.1, 2 #2.2, 3 #2.3
2.1 15276 1 $0.90 bolt M7-1.25 x 45 flange (10 hex)
2.2 14936 1 $0.80 bolt M7-1.00 x 33 (10 hex)
2.3 00366 1 $0.90 bolt M7-1.00 x 48 (10 hex)
2.4 00366.1 1 $1.50 bolt M7-1.00 x 40 (set has 48)
2.5 00366 1 $0.90 bolt M7-1.00 x 48 (10 hex)
2.6 14936 1 $0.80 bolt M7-1.00 x 33 (10 hex)
2.7 15276 1 $0.90 bolt M7-1.25 x 45 flange (10 hex)
2.8 00011 5 $0.50 nut M7 (10 hex)
03 14854 1 $7.00 gasket cylinder head
04 14895 1 $6.00 gasket cylinder base
05 16910 1 $3.00 gasket crankcase
06 52646 1 N/A gasket intake restricted (20mph)
06 17073 1 $3.00 gasket intake (25 and 30mph)
07 16912 1 $15.0 gasket kit 3, 4, 5, 6
# part# qty price description 2. Engine mounts
01 19886 1 $6.00 bolt engine mount M8-1.00 x 140
01 20453 1 N/A bolt for up-exhaust M8-1.00 x 145?
02 20534 1 $4.00 spacer tube ∅8 x ∅14 x 18
03 17994 1 $11.0 R Flexibloc ∅8.0 ∅32.0 x 23
03a 17994a 1 $8.00 R red rubber ∅9.7 ∅28.8 x 18
03b 17994b 1 $8.00 R center tube ∅11.3 ∅8.0 x 23
04 19888 1 $3.00 ground cable, engine-to-frame
05 21014 2 $3.00 step spacer ∅8 x ∅12-17 x 10.5
06 20789 1 $11.0 L Flexibloc ∅11.0 ∅32.0 x 23
06a 20789a 1 $8.00 L red rubber ∅12.4 ∅28.8 x 18
06b 20789b 1 $8.00 L center tube ∅14.0 ∅11.0 x 23
07 17523 1 $2.50 nut locking M8-1.00
08 16541 1 $0.20 washer ∅8
09 20790 1 $6.00 plastic tube ∅8.0 ∅11.0 x 23
10 17661 1 $3.00 bracket for variator cover
11 00011 4 $0.50 nut M7 (10 hex)
12 01527 7 $0.50 lock washer ∅7
13 15276 2 $0.90 bolt M7-1.25 x 45 flange (10 hex)
14 14936 2 $0.80 case bolt
15 01526 2 $0.50 nut M6 special?
16 01172 2 $0.20 washer Ø6
17 17120 1 $5.00 bracket spring retainer variator
17 21282 1 $6.00 bracket spring retainer 1-speed
18 00968 2 $0.70 bolt M6 x ??
19 15933 2 $7.00 belt tension springs (each)
20 00366 2 $0.90 case bolt M7-1.00 x 48 (10 hex)
21 00010 2 $0.30 nut M6
22 15934 1 $9.00 Flexibloc lower Ø6 x Ø?? x ??
23 00050 1 $0.70 bolt M6 x 25?
24 21709 1 $4.00 lower engine mount plate right
25 21710 1 $5.00 lower engine mount plate left
26 17354 1 $3.00 bracket variator cover
Motor Mount Bushings (Flexiblocs)
top: #2 tube, #6 left Flexibloc, #3 right Flexibloc
bottom: #6a red rubber, #3a red rubber
The red rubbers replace just the old black rubber part. The old bushing metal shell and metal center tube are re-used. The shell is not removed from the frame so no special press tool is needed. Instead the black rubber is removed with a knife.
But the red rubber holes 9.7 and 12.4 are too small for the center tubes 11.3 and 14.0. The small hole must be widened by drilling. The large hole is a very tight fit without drilling. Drilling is recommended for both.
# part# qty price description 3. Cylinder and head
01 53505 1 $140. cylinder E with piston J (20 mph)
01 53505 1 $140. higher top deck, lower compression
01 23460 1 $180. cylinder AA w/piston AA (25 & 30)
01 23460 1 $180. cylinder AA w/piston AA (25 & 30)
01 23460 1 $180. cylinder C with piston C (25 & 30)
01 23460 1 $180. cylinder C with piston C (25 & 30)
01 23460 1 $180. cylinder C with piston C (25 & 30)
01 23460 1 $180. cylinder E with piston E (25 & 30)
01 23460 1 $140. cylinder C with piston C good-used
01 23460 1 $140. cylinder C with piston E good-used
02 14721 1 $12.0 decomp valve kit
03 14821 2 $10.0 piston ring (pre-6/76) Ø39 x 2.0 FG
03 22148 2 $12.0 piston ring (6/76-on) Ø39 x 2.0 GI
04 15094 1 $12.0 piston pin Ø13 x 30
05 00658 2 $2.00 piston pin clip Ø13
07 19885 1 $35.0 cylinder head complete
08 00053 2 $1.00 rivet for ID plate
09 21294 1 N/A engine ID plate
10 00059 1 $1.00 spark plug gasket ring
11 01547 1 $3.50 spark plug NGK BR6HS
12 15025 1 $8.00 decomp valve bare
13 14919 1 $7.00 mounting lug
14 14855 1 $7.00 guide
15 14897 1 $7.00 gasket
16 14987 1 $4.00 washer
17 15007 1 $4.00 spring
18 15099 1 $6.00 valve link
19 00018 1 N/A cottor pin, use small bent nail
21 22156 1 $3.00 wire guide
Piston (at skirt) to cylinder clearance: new is 0.005 to 0.01 mm (0.0002 to 0.0004″), max is 0.05 mm (0.002″).
This is a very small clearance, measured at the bottom of the piston, allowed by the all-aluminum cylinder.
Usually pistons are measured at the bottom skirt, called “lower” below, because when cold, that is the widest part.
The bottom is slightly wider than the top, because there is less material, and therefore less thermal expansion.
When the piston is hot, the bottom and top are the same. The whole piston expands, as does the cylinder.
Motobecane measures just below the rings, called “upper” below. On these pistons lower is 0.02 mm bigger.
Motobecane original pistons have no marks on top, listed below as “(M)”. Inside has the M logo (some also AJ3).
< Some original replacement pistons have this logo stamped on top, listed as “(Θ)”. Inside says FRANCE.
They also have a size letter stamped on top. These were original replacements from Motobecane USA.
Other vintage aftermarket have no logo on top, listed below as “(O)”.
# part# price description x skirt 4. Piston
73 22273 $70 piston W 38.92 for 38.93 cyl
74 22274 $70 piston AA 38.93 for 38.94 cyl
75 22275 $70 piston A 38.94 for 38.95 cyl
76 22276 n.a. piston C 38.95 for 38.96 cyl
77 22277 $75 piston E 38.96 for 38.97 cyl
78 22278 n.a. piston G 38.97 for 38.98 cyl
79 22279 n.a. piston J 38.98 for 38.99 cyl
80 22280 n.a. piston L 38.99 for 39.00 cyl
81 22281 $75 piston N 39.00 for 39.01 cyl
82 22435 $75 piston P 39.01 for 39.02 cyl
82 22435.1 $75 piston O 39.11 for very worn
# part# qty price description 5. Intake pipe
01 16673 1 N/A intake (variator 25mph) Ø16 x 10
01 16619 1 $33.0 intake (var 30 pre-3/77) Ø17 x 12
01 00000 1 $21.0 intake Malossi 022066B Ø19 x 15
02 01176 3 $0.90 lock nut M6
03 01172 3 $0.25 lock washer Ø6
04 52646 1 N/A intake gasket restricted (20mph)
04 17073 1 $7.00 intake gasket (25 & 30 mph)
05 00796 2 $2.50 stud M6 x 31
06 53496 1 N/A intake pipe thin long (1-sp 20mph) Ø19
06 21201 1 $13.0 intake pipe long (1sp 25&30mph) Ø19
06 22899 1 $16.0 intake pipe long (var. 30 3/77-on) Ø19
07 21202 1 $6.00 support bracket
08 23018 1 $1.50 carriage bolt M6
# part# qty price description 6. Crank and case
01 19608 1 N/A crankcase with seals (25 & 30)
1.1 19608.1 1 $15.0 left case half bare (25 & 30)
1.2 19608.2 1 $15.0 right case half bare (25 & 30)
1.3 19608.3 1 N/A crankcase (20mph) with a ridge that
1.3 19608.3 1 N/A only allows a 20mph cylinder to fit
02 00011 4 $0.50 head nut M7-1.0 thick, 10hex
03 18921 4 $0.30 washer M7
04 14716 4 $4.00 cylinder stud
05 19089 2 $7.00 crank seal Ø15 x Ø21 x 4
06 54977 2 $14.0 special crank bearing 6302QR
07 15855 1 $15.0 needle bearing Ø13 x Ø16 x 14(13.6)
08 19609 1 $150. crankshaft Ø16 Ø15 pre-’80 for 6302QR
08 19609 1 $150. less threads for dome square-hole nut
8.1 19609.1 1 $150. crankshaft Ø16 Ø15 ’80-on for 6302QR
8.1 19609.1 1 $150. more threads for large hex flywheel nut
8.2 19609.2 1 $150. crankshaft Ø15 Ø15 ’80-on for 6302
8.2 19609.2 1 $150. machined to take regular bearings
09
10
11
12
13
Crankshafts: top 19609, bottom 19609.2
Motobecane Crankshafts: are the same for variator and non-variator pulley-clutches.
Top is used, pre-1980, shorter right side threads. Takes special 16mm bearings 6302QR 16x42x13.
Bottom is new 1980-later original, machined to 15mm at bearings, to take ordinary bearings 6302 15x42x13.
Myrons offers new pre-1980 crankshafts, that take special 6302QR bearings.
Myrons offers a new original 1980-later crankshaft that has been machined from 16mm to 15mm at the center where the bearings press on. The press fit is precise and correct. The piston pin and needle bearing are new, included, and factory sealed in wax, that peels off. Two 6302 bearings, and two 15x21x4 seals are included. Price is $180.
It is long enough to take the 1980-later hex nut, sold separately at $10. But it will also take the pre-1980 square-hole nut, if the extra threads are ground off.
# qty part# price 7. Variable Pulley-Clutch
01 1 23695
01 1 24659
02 1 16845
03 1 17797
04 1 19262
05 1 20638
05 1 23398
06 3 16723
07 4 15356
08 2 22401
09 1 16842
10 2 14562
10 x 14931
10 x 14932
10 x 14933
11 1 14561 $2.00 external circlip 15 x 1.0
12 1 22925
13 1 17455
14 1 14587
14 1 22896
15 1 20683
16 1 21946
17 1 22924
18 2 22402
19 1 15187
20 2 20456 $0.00 rivet post
21 1 14712 $0.00 needle bearing
22 1 14563 $2.00 internal circlip 22 x 1.0
23 1 15349 none o-ring 2.5 x 20 (25od)
24 1 19851
25 1 17426
26 1 17425
Pedal and Pulley Parts
# qty MB#
5 1 14158 circlip external 16 x 1
6 1 15998 washer 16-26 x 1.0
7 2 14179 pedal shaft bushing 16-24 x 19
8 1 16566 circlip inverted external 16 x 1
9 1 14863 shim washer 16-30 x 0.1
9 1 14865 shim washer 16-30 x 0.3
9 1 15001 shim washer 16-30 x 0.75
11 1 14153 washer 16-27 x 2.0
15 1 00006 pedal pin 9.0
16 1 20738 spacer 16-20 x 13
17 2 20697 pedal cap for original pedal