With the noose of emission norms getting tighter by the day, motorcycle manufacturers have started moving away from two-stroke powertrains and adopting more efficient four-stroke engines. However earlier this year, KTM pleasantly surprised us with their announcement of a new fuel-injected two-stroke powertrain. Called Transfer Port Injection or TPI, this technology can lead to the resurgence of two-stroke motorcycles in the dirt bike segment. The KTM 300 EXC TPI and the 250 EXC TPI are the first motorcycle to be armed with TPI, here is a detailed photo gallery of these bikes –
TPI involves twin fuel injectors firing directly into the transfer port, smoothing out the power delivery and reducing fuel consumption.
The engine also gets a new engine management system and ECU which use sensors to determine the perfect ignition and injection timing.
With TPI, riders no longer have to worry about adjusting the jetting on the carburettor for different environments.
Powering the 300 EXC TPI and 250 EXC TPI is a single-cylinder engine mated to a six-speed transmission, displacing 293cc and 249cc respectively.
Updates for the EXC bikes aren’t restricted to TPI, they also get a redesigned air filter box, oil pump and fuel tank.
The lightweight chrome molybdenum frame has been adapted to house the oil filler cap and the hose for the oil tank.
Both these bikes ride on 21-inch front and 18-inch rear wheels with fully adjustable WP suspension. Braking hardware has been supplied by Brembo.