T6 has always sheared quite a bit in any shared sump bike. ITs not just T6 either, that will happen with any 5/40/ Spread is too great.
Kind of odd with the foam and think ZeeOsix has a point with the oil being cold. I used to have a star 1300 tourer with the glass site window, I never saw such foaming, then again never used T6 but quite a few others have with no issues.
Just a shot in the dark here but are you sure your crankcase wasnt overfilled just a bit?
The 20/50 M1 VTWIN will actually thicken up in a non shared sump bike, Amsoil behaves in much the same way. So for shared sumps I think the 20/50 is more suited then non shared sumps, in a non shared sump you can be pushing close to a 60 weight after 5000 miles, something I personally wouldnt care for but in a shared sump will stay stable and according to others maintain shift quality. If these weren't considered high quality oils, in the old days they would be accused of "oxidizing" !
Well, I got the new tire on the back of the Road King installed the other day by an indy shop. All set for a ride up to Maggie Valley for a few nights, Of course, I cant get that perfect weather forecast (last couple years been dicey weather wise though we normally get lucky) and why I was in a rush for the new rear tire before we left. Thankfully found a Dunlop American Elite with very recent date code on it. Normally I prefer the Harley Dunlops, they got us through so many storms over the years, dealers all out of stock (covid related and think we are at the point they are catching up with production and why I ever found this one) ... always been curious about this Dunlop anyway.
Think we are going to get wet the first two days... but maybe we will get lucky ... odds not in our favor at 40 to 60% chance of storms though...
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