Very random question - why don't modern bikes, especially large V twins, need decompressors? This question was asked by the 90 year old petrol head I do some gardening for. He is mostly into American cars but as a lad had a lot of brit bikes, all kick start, all with decompressors to aid starting. He can't see how a modern bike, with a tiny battery can develop enough ooomph to start. I told him some of the bigger bore new Harleys do have electronic decompressors and possibly in general modern bikes have lower compression ratios, lighter smaller engine internals etc but he is not convinced. Any additional thoughts?
i have three old British singles all with decompressors , their objective is to aid getting the piston just over the top of the stroke then with a complete length kick start should make it easier to fire the bike into life. The older singles remember had very long strokes as opposed to the modern day bikes.
On an old M900 you need to keep the connection lead connections clean and the battery well charged or it won’t! On the newer Ducatis it may have something to do with better efficiency of electronic ignition and fuel injection at low revs?
That's just what I was going to ask. I've a 1098 and when the Panigales were introduced I questioned the even smaller battery. Was told by the dealer that there was a decompressor built into the bike to allow the small battery to spin the engine over during starting
I don't believe that the Desmosedici had a decompressor but first Panigale certainly did, but then again, what do I know.
I'm probably confusing it with a memory I have of watching a video of the centrifugal decompressor when the Panigale first came out Chris.
