All American, me and my dad have been running MC-1 at 50:1 in 85&86 motors for five years now and have never had a single problem. I don't know if it is the oil and mix ratio or the fact those motors just won't die. They all have CT racing porting, FMF gold series pipes and smooth bored carbs to (Well I forgot what size). They have all ran extremely well with amazing longevity.

In my 92 I run H1-R at 50:1 but am going to 32:1 this summer.

Off topic I also run SI-7 in my 72 gt750 and would recommend it in any application that uses oil injection.