First, those that choose to run Amsoil have also chosen not to listen to those that have hundreds of hours of use experience with the stuff. But it IS your engine and you can do whatever you want with it. Second, there is not one person that can provide a vaild or suitable answer for mixing oil at 100-1. The only benefit is keeping a lazy person lazy by minimizing the clean up on a plane. It can't cool, It provides minimal lubrication, and leaves zero excess for carrying away combustion and ingested debris. From my perspective it's only a reversed status symbol. If the only reason you go out to the field is to show off a clean and well polished plane, why bother going at all? Take a picture with you instead of the plane and pass it around. Saves a lot of work and you can use a smaller mode of transport.

If you're not racing at high rpm and high heat loads, 25 and 30-1 mixes only causes the development of sludge. The engine will not maintain a cht high enough to alter the viscosity of the oil to any great degree. Hence the syrup all over your plane. It's straight oil with a lot of unburned gasoline. The black stuff will be largely high levels of carbon rather than fine metal particles from the ring seating process. Seating the ring IS NOT the most important part of a break in, it's truly only a very small part. Keeping the engine cold by using a rich mix actually hinders the break in process by preventing the proper thermal cycling of a cast engine case and cylinder head. THAT'S the most important part of a break in, and the part that requires the most time.

Ultra rich oil mixes suggested by manufacturers are there to protect the manufacturer from you, the end user. They are well aware that many people will tune an engine too lean for maximum rpm and fail to consider air flow and cht's, cooking off the engine on the first or second run. They also know that a lot of people will bench run them for extended periods of time at maximum rpm and think that the prop is providing all the airflow the engine needs. Then there's the group that will run them at max rpm on a cowled airplane while sitting over the hot asphalt at the club field for extended periods of time. They KNOW this (they read these forums and still get lot's of returned engines) and so provide instructions to protect themselves from the ignorant. Flood an engine with enough oil and it can be nearly impossible to keep it running, especially at lower rpm counts. Our carbureators are not jetted for these kinds of mixtures and require user modifications to do so effectively. As the oil content in the fuel is increased, the requirement for more oxygen also increases to provide a combustible mix. Straight gas requires an air-gas ratio of 14.7-1 to burn. A two stroke mix runs around 16-1, air-gas-oil, and goes up as the oil increases.

If you break in an engine at ratios from 32-50/1, and tune the engine to avoid a peak or lean of peak rpm, provide adequate cooling, and thermal cycle the engine using normal flight methods the engine will last for a very long time. Avoid hovering, torque rolls, and harriers for the first few tanks. After about 3 hours of running time (notice number of gallons was not used) the engine is as broken in as it will ever be. A little before that is true in the vast majority of engines, but three hours covers them all. You can start doing the fun stuff after about the 5th or 6th tank, but don't over do it, and keep engine cooling forefront in your thoughts when doing so.