The Decompression feature reduces compression during the starting procedure, which means that up to 70 % less effort is needed to pull the starter cord, the ignition spark is stronger and a better air-fuel mixture is produced. The result is a fast and reliable start. Pressing the blue HappyStart button opens up the valve. On the upstroke of the piston (compression stroke) a precisely metered portion of the combustion air escapes, reducing the effort needed to start the engine. However there is still sufficient compression to ignite the mixture. The high combustion pressure generated by the first power stroke automatically shuts the valve. Maximum compression is restored.
