I have a 2017 390 Race Edition (which I love) and it of course has the closed chamber Sachs forks up front.
I think im going to switch to Spectro Golden ultra light. Even 40C is a very high starting temp, so viscosity may be even thicker when I begin riding. Well, according to the manual the bike comes with Motul Factory Line light 5 and it has a centistoke of 18!!! And then, since it has a low VI of 138, it thins down to 4.20 IF you can even warm it up to 100C, not likely. Dont get me wrong, i LOVE the bike but it feels a bit stiff when I start riding and then loosens up after an hour or so. This all explains a lot to me with my Xtrainer. A higher number in the column Recaculated Viscosity Index (VI) means the oil will be more stable. Reported cSt (centiStokes) This is how it really flows (when the temp is 40C) And THEN it may change to a thinner viscosity when it gets warmer/longer riding. I was looking around the interwebs and found this.Įven though fork oil products list 5w, 10w etc on the bottle, the REAL viscosity is in the second column from the left, next to nominal weight.
