It boasts “four-channel technology”, designed to optimise fuel consumption and give sufficient reserves of power to tackle big timber. The result is that the unburned fuel emissions emitted to the environment with the exhaust, due to the scavenging losses typical of two-stroke engines, are a thing of the past. “Stratified scavenging technology” is the term for the layer of air that separates the spent charge in the combustion chamber from the fresh working fluid that follows in the crankcase. What escapes as the scavenging loss with the exhaust emissions is therefore not fresh fuel but the fuel-free air barrier.
We are not sure if this sounds a bit like Efco’s Compression Wave Technology but, technicalities aside, the exhaust contains fewer pollutants and the strict requirements of the future EU exhaust emission directive (stage II) are met. On the ground, it converts to a smell-free test. If it wasn’t for the noise and the sawdust, nobody would know we are using two-stroke chainsaws. What’s more, Stihl assures us that this technology reduces fuel consumption by up to 20 per cent compared with a conventional two-stroke engine.
Another technical detail that puts this saw in the premier league is the long-life air filter system. It uses centrifugal force and a three-dimensional air flow to remove larger, heavier particles of dirt and route them away from the intake air. The largely particle-free air is then directed to the filter via a pre-separation channel, thus relieving the downstream filter elements. It’s easy to understand how that would provide a long-life system with extended intervals between filter cleaning.
The saw also has a new anti-vibration system. It uses a combination of Cellasto AV elements and springs between the engine unit and handles. You can literally feel the lack of vibration. By combining the rubber-like elements and springs, Stihl scores 2.1m/s2 on the left handle and 2.6m/s2 on the right (factory measurements). Vibration is further reduced — and guiding behaviour improved — by the RSC saw chain.
Controls are simplified into a single-lever master control. Starting, with no kickback, is assisted by a microprocessor-controlled ignition system that also monitors running for a smooth performance. And there is a host of useful features such as ElastoStart starter grip to buffer the jerks when firing up and a see-through fuel tank for at-a-glance information on the fuel level.
You need to dig into your wallet for such a powerful saw packed with technology — but we reckon it’s worth it.
Have you registered with us yet?
Register now to enjoy more articles and free email bulletinsSign up now