Ok..took a trip with 3 Qts.Delo 15-40 and 7.5 ozs of VEP in a '90 HD Evo motor..had @ 1000 miles on the oil before we left..at @ 1500 miles I was down 1/2 Qt..did not add any oil..everything worked very well..oil pressure at 22# hot @ 60 mph..remember that I have a S&S oil pump..well..got to the Vicksburg battleground and started to putt around the park..90*+ outside..everything going good till we get in a traffic jam..at idle(1000 RPM) the oil light came on..so I knew the oil was very thin..the engine sounded normal (proably the VEP helping here)..so out of the park I go down to the local Wally World..the only thing I could find to thicken the oil was ..now don't passout.. was Bardahl No Smoke..in goes 8 ozs..fire up bike and watch the oil pressure go to 25# then settle down to 22#..ran great all the way home..@ 2500 miles total on the oil..so when I got home I drained the oil and put in 25-60 RevTech oil with 7.5 ozs VEP ( anybody know anything about this stuff??) Took @ 150 mile 90* ride today and it seems to work very well.. no heat issues..25# on the gauge..15# at idle..so there you have it..run at least 20-50 in the summer ..I'm going back to the 15-40 in the winter..love the VEP in whatever grade of oil..I'll be gone for the next week (work) so I won't be able to answer any questions ..that's this post is long..
see ya