After 4 years and 2 YZF 's , I'm back into 2-strokes. Got a new YZ 250 and I love it. I always used 100-1 amsoil with great results but when i finally ran out, i was told by an amsoil dealer that the new 50-1 oil was better. I didn't get an explanation. Anybody out there using this? Are there any amsoil retailers that sell for less? What is wc-3 protection? Thanks from this 1st-time poster.