Hi Mike:

I have a ZDZ80 that I'm breaking in. I ran two gallons of 40:1 using the Penzoil petroleum based oil I ordered from RCS. I am now running 40:1 synthetic. I'm using some stuff called Silkolene that I picked up from my LHS.

When I was running the Penzoil I was getting good RPM's of 6600 +-. Now that I've gone to the 40:1 synthetic the best I'm getting is 6150.

So the question is will performance, RPM wise, get better when I go to 50:1 synthetic or does oil mixture have anything to do with RPM's ?

Or is it possible that I need to change my plug?

Thanks.