Rocket Man, Just tell me this. Why is the SRM warranty voided if you use superior multi grade oil and an oil filter? If you value your engine you would not omit to fit a filter or use non detergent mono or multi grade oil in your newly built engine. Relying on a centrifugal tube which gradually fills up and blocks the oil supply from reaching the big ends is bizzare to say the least. Technology has moved on, and in their final years BSA were recommending multi grade oil. I have to doubt the wisdom of advocating the use of mono grade oil which contains no detergent, when clearly the sensible thing to do is to remove the muck with a good filtration system. When the Rocket 3 was released it was fitted with a full flow oil filter which can be retro fitted to the A10. I am not sure either what fuels the paranoia about anti wet sumping valves. The principle employed by these valves was incorporated into the Veloctte lubrication system, and I am not aware of a plague of Velocette engines being wrecked due to this component. The problem of wet sumping is a by product of the laws of physics: gravity cannot be circumnavigated. All, and I do mean all A10s will wet sump no matter how new or pristine your oil pump is. The only negotionable variable will be how long it takes to do it. But rest assured it is not a case of if, but when. Here is something else to consider. I have read many times that one of the benefits of using mono grade oils is that the engine is less likely to leak, well that might be so, but I remain to be convinced. The other side of the argument which is much more compelling, is the fact that mono grade oil is much slower to circulate when cold, and your engine is deprived of oil at the very time that it really needs it, that is to say on start up. If you want to get decent life from your engine run it on synthetic oil with a filter, and always put Redex in your petrol. One final thought, if BSA were advocating the use multi grade oil that should be reason enough to use it. We longer turn mirrors to face the wall when lighting is about, or do we? some of us?