It is thought the engine was originally developed as the Victory Freedom V2 engine before Polaris axed the brand.
So what’s happening with the current air/oil-cooled Thunderstroke in the Chief, Roadmaster and Springfield models?
According to the latest patent filings in the US, the Thunderstroke will be updated with variable valve timing, most likely to meet stringent Euro 5 emissions targets being introduced from January 2020.
Variable valve timing has been around for ages in cars and is known as VVT-i and VVTL-i in Toyota, MIVEC in Mitsubishi, VVL in Nissan and VANOS by Ford, BMW, Ferrari and Lamborghini.
Honda was the first to introduce it to motorcycles and it is now being progressively introduced to other Japanese and European motorcycles such as BMW, Ducati, Suzuki and Yamaha.
Already many of our popular motorcycle models have been axed because they can’t meet the Euro 4 requirements and more are likely to be axed next year under Euro 5.
One of the solutions to the tighter emissions laws could be variable valve timing which makes the engine more flexible in different conditions, resulting in increased fuel economy, lower emissions and improved performance, particularly torque.