The Polini Air and Polini H2O are two names from the pocket-bike range of Polini Motori, the Italian company from Alzano Lombardo. In the minimoto class the naming follows the cooling system, and cooling is what separates the slowest and the fastest machines of the category.
Polini Air at a glance
| Maker | Polini Motori, Alzano Lombardo (BG), Italy |
|---|---|
| Models | Polini Air, Polini H2O |
| Class | minimoto (pocket bike) |
| Air-cooled use | Junior categories, with limited power |
| Water-cooled use | all other categories |
| Air-cooled output | 2–3 hp (Chinese kits), 6–7 hp (Italian kits) |
| Liquid-cooled output | 11 hp (Chinese kits), 14–15 hp (Italian kits) |
| Top championship output | up to 18 hp |
| Engines used in the class | 39 or 50 cc two-stroke, 90 cc four-stroke |
| Model specifications | not published |
No published specifications for the Air or H2O were found. The power and cooling figures are those of the minimoto class from the Italian Wikipedia article on minimoto, and are not claimed as measured outputs of these models.
History of the Polini Air
Polini Motori began in 1945 in Alzano Lombardo, near Bergamo, as a bicycle workshop run by Battista Polini; when Vespa and Lambretta scooters arrived in the late 1940s the firm switched to tuning parts and has stayed in that trade, now selling in 64 countries. Minimoto production started in the 1990s and gave the company a second, racing-oriented line alongside its cylinders, variators and exhausts.
Cooling is the great dividing line within the class. Junior categories use air-cooled engines with power deliberately limited, while almost every other minimoto is liquid-cooled. The difference in output is large: air-cooled cylinder kits deliver about 2–3 hp when they come from Chinese suppliers and 6–7 hp from Italian ones, whereas liquid-cooled kits reach 11 hp from Chinese suppliers and 14–15 hp from Italian ones, and machines built for major championships can produce up to 18 hp.
A typical minimoto measures about one metre in length and sixty centimetres in height, with a seat a little over forty centimetres from the ground and a total weight of just over twenty kilos. Engines are almost always two-stroke units of 39 or 50 cc, with four-stroke 90 cc engines also used. These machines run on circuits, private land and woodland, not on the public road.
Design and features
- Naming by cooling: the Air and H2O names refer to the air- and water-cooled sides of the range.
- Air-cooled Junior class: lower output and simpler maintenance.
- Liquid cooling: more than twice the power of an Italian air-cooled kit.
- Polini tuning background: the maker’s main products are performance cylinder kits and exhausts.
Polini Air versions
- Polini Air: the air-cooled designation.
- Polini H2O: the water-cooled designation.
- Junior specification: air-cooled and power-limited, as in the class rules.
- Championship specification: liquid-cooled, up to 18 hp.
Other Polini pocket bikes are the Polini 910, the Polini X and the road-legal Polini XP. More in the Polini collection.
Sources
- Minimoto, Italian Wikipedia: cooling systems, power figures, dimensions, engines
- Polini, Italian Wikipedia: company history and minimoto production
- Polini, English Wikipedia: company history and products
