Engines.

Model MOV

Model MAC

Model MSS

Type

One Cylinder OHV - 4 stroke

One Cylinder OHV - 4 stroke

One Cylinder OHV - 4 stroke

Bore and Stroke  

68 mm. x 68.25 mm.

68 mm. x 96 mm.

81 mm. X 96 mm.

Cubic Capacity (Swept Volume)      

248 c.c.

349 c.c.

495 c.c.

Rated Horse-Power (A.C.U. Rating)

2.5 H.P.

3.5 H.P.

5 H.P.

Tappet Clearances (For Running) 

Inlet .003-in. Exhaust .006-in.

See Page 66.

Inlet .005-in. Exhaust .010-in.

Tappet Clearances (For Timing)

Inlet .010-in. Exhaust .015-in.

 

Inlet .025-in. Exhaust .025-in.

Position of Engine Serial Number

Stamped (following the serial Letters) on near side of Crankcase below Cylinder. See page 43, Fig. 20.

Gearboxes

4 speeds. Operated by Right-hand Pedal on all three Models. Downward movement of Pedal engages higher gear. Pre-war Models and some war-time machines operate the opposite way.

Ratios : With Standard Sprocket

Top:

6.35 to 1

Top:

5.5 to 1

Top Solo:

4.9 to 1

 

Third:

8.45 to 1

Third:

7.3 to 1

Third:

5.91 to 1

 

Second:

11.1 to 1

Second:

9.6 to 1

Second:

7.76 to 1

 

First:

16.1 to 1

First:

14  to 1§

First:

11.25 to 1

Position of Gearbox Serial No.

Stamped on rear of housing.

 § 16.8 on WD /MAC., 18.17 on MAF.

 

Tanks.

Fuel Capacity

2.5 gallons

11.35 litres

2.5 gallons

11.35 litres

3.5 gallons

15.9 litres

 

Oil Capacity

½ gall.

2.27 litres

½ gall.

2.27 litres

½ gall.

2.27 litres

 

Sprockets

Primary Drive - driver

19 teeth

22 teeth

23 teeth

Primary Drive - driven 

44

44

44

Final Drive - driver

19

19

Solo 18T. 

S/C 16T.

Final Drive - driven

52

52

46 teeth

Chains

Primary Pitch & Width .5-in. x .305-in. .5-in. x .305-in. .5-in. x .305-in.

 - Roller Diameter

.335-in.

.335-in.

.335-in.

 - No. of Pitches

74

75

68

Rear  - Pitch & Width

.5-in. x .305-in.

.5-in. x .305-in.

.625-in. X .380-in.

 - Roller Diameter

.335-in.

.335-in.

.4-in.

 - No. of Pitches . .

108

108

99

 

Height to Top of Saddle

27.5-in.

27.5-in.

28-in.

Wheel Base

52.25-in.

52.25-in.

55-in.

Width over Handlebars

27.5-in.

27.5-in.

29-in.

Wheels:   Rims

WM2 x 19

WM2 x 19

WM3 x 19

Tyres:               Front

26-in. X 3.25-in.

26-in. X 3.25-in.

26-in. X 3.5-in.

                        Rear

26-in. X 3.25-in.

26-in. X 3.25-in.

27-in. X 4-in.