I bought some of that synthetic 140 wt from Graingers, but it's pretty runny stuff. It was all on the garage floor in a week. 90 wt hypoid gear oil seems a lot more viscous. I made a mix of 50 wt engine oil and STP for the 850's swingarm. It took several weeks to leak out.
kommando, where did you hear about the 100C temperature thing? I've been using Redline GL-4 rated oil in the gearbox mainly because of the GL-5 controversy, but it's hard to find locally. If GL-5 is really ok, I'd rather switch to it as it is much easier to obtain.
Debby