T5 Specification

In standard form the T5 is still something special in comparison with a normal PX type Vespa, here is information which shows you clearly what makes a T5 special.

Also we have shown you what can be achieved performance wise with a little modification.

Standard T5 125

Ignition: Electronic

Spark Plug: NGK B9ES

Top Speed: 62mph

Gearing:

4 Speed Constant mesh

Clutch 20tooth
Primary gear 68tooth

Primary shaft to rear axle

1st Gear = 12:58
2nd Gear = 13:42
3rd Gear = 17:38
4th Gear = 21:36

Gear oil: SAE 30

Dynamo: 12V/90W

Rims: 2.10" wide, 10" diameter

Tyres: 3.50-10

Lubrication: 50:1 (2%)

Dry weight: 108kg

Bore x stroke: 55mm x 52mm (123,5cm³)

Compression: 11,3:1

Power: 9kW/12BHP at 6700rpm (about 10BHP at the wheel)

Timing: 16° BTDC

Carburator: Dell´Orto SI24/24G

Jets:

Main jet calibrator 120
Mixer tube BE4
Main jet 112 (110 with autolube)
Slow running jet with air enlarged filter hole(s): 100/100
Slow running jet with standard air filter hole: 50/100 (default)
Starter jet 60

T5 with Malossi 172cc kit

Spark Plug: NGK B9ES

Top Speed: 75mph (average)

Gearing:

4 Speed Constant mesh

Clutch 20tooth (sometimes exchanged for a 21tooth)
Primary gear 68tooth

Primary shaft to rear axle

1st Gear = 12:58
2nd Gear = 13:42
3rd Gear = 17:38
4th Gear = 21:36

Lubrication: 50:1 (2%)

Bore x stroke: 65mm x 52mm (170cm³)

Compression: 11:1

Power: 15bhp at the wheel (based on an average depending on exhaust used)

Timing: 16° BTDC

Carburator: Dell´Orto SI24/24G (most popular choice)

Jets:

Main jet calibrator 120
Mixer tube BE4
Main jet 125 (based on a average)
Slow running jet with air enlarged filter hole(s): 100/100
Slow running jet with standard air filter hole: 50/100 (default)
Starter jet 60

Malossi 172cc & Reed Valve conversion

Spark Plug: NGK B9ES

Top Speed: 80-90mph (average)

Gearing:

4 Speed Constant mesh

Clutch 20 tooth (sometimes exchanged for a 21 tooth or even a 22 tooth)
Primary gear 68 tooth

Primary shaft to rear axle

1st Gear = 12:58
2nd Gear = 13:42
3rd Gear = 17:38
4th Gear = 21:36

Lubrication: 50:1 (2%)

Bore x stroke: 65mm x 52mm (170cm³)

Compression: 11:1

Power: 17bhp-20+bhp

Timing: 16° BTDC

Carburator and reed: for carb usually a minimum or 30mm bore used too many combinations of reed and carb to list

average Jetting:

Main: 130+

Idle: 55+

for dellorto

atomiser: usually a 264 or above