Are you refering to the split fire plug? If so they work just fine. But the old origional plugs do also. So I really don't see any advantage of using them. I do use them in my sons dirt bike, they seem not to foul out as often when he mixes it to rich.
As far as the engine cleaner, do you mean inside the engine? If you need an engine cleaner inside the engine its time to freashen it up with an overhaul.
If you are talking about outside of the engine, I use Castrol Super Clean, I buy it by the gallon and use it straight. (no water mix) It will remove most any petroleum product, will clean the kitchen floor, removes all wax, and is biodegradeable. Cleans white wall tires with out scrubbing also.
