The Rotax Max 125 Engine is a two-stroke engine designed by Rotax, part of Bombardier Recreational Products (BRP), to provide cost-effective but high speed kart racing. Built in Austria, the engine is liquid cooled, equipped with a balance shaft, integrated water pump, electric starter and centrifugal clutch. Its combination of onboard electric starter and centrifugal clutch simplifies its operation. This concept is called TaG (Touch-and-go). The Rotax Max was introduced to karting in 1998, easy to use and very reliable, it almost immediately began to gain market share from other slower or more expensive classes. The engine is offered in different performance configurations. Engine versions There are several different versions of the engine. The original has a power valve and produces around , and is used by racers aged 15 or older. The DD2 is another fully powered version which has two gears and is direct drive in that the axle goes through the engine without need for a chain. 125 MAX "base" configuration: at 11,500 rpm Maximum rpm 14,000 rpm. recommended as of 16 years has a cylinder with exhaust valve 125 Junior MAX configuration: at 8,500 rpm Maxiumum rpm 14,000 rpm recommended for juniors from 13 to 16 years has a cylinder without exhaust valve 125 Mini MAX engine configuration: at 8,500 rpm Maximum rpm 12,500 rpm recommended for children from 10 to 13 years has a cylinder without exhaust valve, and intake and exhaust restrictors 125 Micro MAX engine configuration: at 6,500 rpm Maxiumum rpm 12,000 rpm recommended for kids from 8 to 10 years same as previous with a different exhaust and radiator, No inlet restrictor, and acceleration stop sleeve, fitting smaller chassis adapted to kids size Based on an evolution concept, each of the above configurations can be upgraded or downgraded to any of the other configurations by replacing various accessories and components. 125 MAX DD2 engine configuration: at 11,750 rpm Maxium rpm 14,000 rpm recommended as of 16 years has a two-speed gearbox operated by shift paddle from the steering wheel, and a chainless drive system Rotax Max Challenge BRP-Powertrain has introduced a single (engine) brand race series for the MAX engine concept - called Rotax Max Challenge . This race series is organized in various classes (125 Micro MAX, 125 Mini MAX, 125 Junior MAX, 125 MAX and 125 MAX DD2) in around 60 countries. Competitors from the national Rotax Max Challenges in