A compression release works to ease the starting of internal combustion engines that have higher than normal combustion compression ratios by allowing them to spin up to starting speed without having to work against the pumping action of the pistons. It does this through a release valve that is incorporated within the cylinder head that vents the cylinder pressure to the outside atmosphere until the engine has sufficient momentum to overcome it. At that point the valve closes and the ignition is engaged. For those of you building or installing a High Performance Engine, K and G Cycles (www.kandgcycles.com) is your source for Compression Releases for your bike. What you may not know is there are different types of Releases available.
Early large displacement motorcycles provided riders with a manual control for this when kick starters were used while later models linked them to the kick lever through a cable for automatic operation. Though it only uses electric start, not kick start, the 2012 Ducati 1199 uses a compression release, which is automatically activated at low engine speed by a centrifugal flyweight on each exhaust cam. This reduces the work of cranking the high 12.5:1 compression ratio engine, allowing a smaller battery and smaller starter motor, for a total weight savings of 3.3 kilograms (7.3 lb).
Whether it is a manual compression release such as Stampedes 36mm x 10mm unit (Part # STCR692) an electric version such as S & S’s (SS904914), or you can even opt for Automatic Compresion Releases – ACR’s – where you simply start the motor as you normally would and the valves regulate themselves based on cylinder compression. When it comes to your ability to start your high HP engine, and start it easily, compression releases minimize the stress placed on the battery and starter. Contact K and G Cycles(www.kandgcycles.com) today to experience the difference.