Tiger Cub T20 1963 - on
Although the styling remained virtually unchanged from the previous couple of years, oil changes became far easier with the fitting of a drain plug at the bottom of the oil tank, thankfully accessible without the need to remove the right-hand side panel.
Yet again there was a number of engine changes and improvements and with another new design crankcase, gone was the distinctive top-mounted points housing, replaced by a side-mounted assembly containing the contact breaker and auto-advance unit operated from the end of the camshaft. As a result, far more accurate ignition timing could be achieved.
To go with the new crankcase were new inner and outer timing side covers, the outer one having an extra hole in it to give easy access to the end of the clutch cable. A rubber 'plug' sealed the hole whilst such access was not required.
Along with giving a change in position of the points assembly, the new crankcase also had a redesigned oil collection chamber allowing better drainage for the oil pump scavenge pick up.
To go with the new crankcase were new inner and outer timing side covers, the outer one having an extra hole in it to give easy access to the end of the clutch cable. A rubber 'plug' sealed the hole whilst such access was not required.
Along with giving a change in position of the points assembly, the new crankcase also had a redesigned oil collection chamber allowing better drainage for the oil pump scavenge pick up.
|
New 'finned' alloy rocker covers replaced the old pressed steel ones that had been a continual source of leaks due to the ease with which they could be over-tightened and distorted.
The arrival of the side-points engine also gave the factory the opportunity to replace the combined ignition and lighting switch with two separate items, one for ignition and a separate one for the lights. The main advantage being less cluttered wiring in the Nacelle, which was redesigned to not only accept the switches but a new grey-faced speedometer and cable. The gear indicator being relocated to the top of the gearbox until disappearing altogether in 1965. Also in 1965, the 'square' head and barrel appeared. The square profile, even though the barrel had just eight fins as opposed to nine on the oval item, gave an increase in fin area. Completing the changes was the fitting of a new slider-block driven oil pump and needle roller big end. Colours for 1963 were Flame, Silver Sheen and black (UK and export markets) and Flamboyant Ruby Red, Silver Sheen and black (USA). 1964-on it was Scarlet, Silver Sheen and black (UK and export markets) and Flamboyant Scarlet, Silver Sheen and black (USA). |
|
Specifications for 1963-on T20 model
Engine
Type: Single-cylinder OHV, unit construction
Capacity: 199cc (12.1 cu in)
Bore/Stroke: 63mm (2.480in) x 64mm (2.520in)
Compression: 7:1
Power: 10bhp (7.5 kW or 10.1 PS) @ 6000 rpm
Carburettor: Amal 32/1, 11/16 inch choke size
Camshaft: Standard - valve clearances In & Ex 0.010in (cold)
Clutch: Wet multiplate
Gears: 4
Cycle Parts
Front Suspension: Telescopic forks, hydraulic damped
Rear Suspension: Swing-arm
Front Wheel: 17 inch (WM2 rim)
Rear Wheel: 17 inch (WM2 rim)
Front Tyre: 3.25 x 17
Rear Tyre: 3.25 x 17
Brakes: 5.5 in dia. Single leading shoe drum front and rear
Petrol Tank: 3 gallons (13.5 litres)
Oil tank - 2 3/4 pints
Gearbox - 1/3 pint
Primary chaincase - 1/3 pint
Front Fork - 1/8 pint
Electrics
Type: Lucas Ignition Coil
Voltage: 6
Charging Type: Alternator / Rectifier
Ignition Timing: 8 degrees BTDC static. 32 degrees fully advanced
Points Gap: 0.014in - 0.016in
Spark Plug: Champion L7 or equivalent
Spark Plug Gap: 0.025in
Engine
Type: Single-cylinder OHV, unit construction
Capacity: 199cc (12.1 cu in)
Bore/Stroke: 63mm (2.480in) x 64mm (2.520in)
Compression: 7:1
Power: 10bhp (7.5 kW or 10.1 PS) @ 6000 rpm
Carburettor: Amal 32/1, 11/16 inch choke size
Camshaft: Standard - valve clearances In & Ex 0.010in (cold)
Clutch: Wet multiplate
Gears: 4
Cycle Parts
Front Suspension: Telescopic forks, hydraulic damped
Rear Suspension: Swing-arm
Front Wheel: 17 inch (WM2 rim)
Rear Wheel: 17 inch (WM2 rim)
Front Tyre: 3.25 x 17
Rear Tyre: 3.25 x 17
Brakes: 5.5 in dia. Single leading shoe drum front and rear
Petrol Tank: 3 gallons (13.5 litres)
Oil tank - 2 3/4 pints
Gearbox - 1/3 pint
Primary chaincase - 1/3 pint
Front Fork - 1/8 pint
Electrics
Type: Lucas Ignition Coil
Voltage: 6
Charging Type: Alternator / Rectifier
Ignition Timing: 8 degrees BTDC static. 32 degrees fully advanced
Points Gap: 0.014in - 0.016in
Spark Plug: Champion L7 or equivalent
Spark Plug Gap: 0.025in