Question for all the tribologists

[ChrisG]

2006 Breva 1100. The paper “Use + Maintenance Book” dated March 2006, and a pdf version of the same dated May 2005 both specify 85-140 weight oil for the gear box.  Every other Moto Guzzi produced reference I have says 85-90 weight. (And this is reflected in threads here on this forum.) 

At some point I decided 85-140 was right, I bought some Motul 75-140 synthetic and have just poured it in.  I suspect I should go with 85-90 or thereabouts, but in the meantime, any issues with the 75-140 stuff (at least during the summer)?

[jrt]

It will be just fine. In fact, it might be an advantage- the 75 is a bit more free-flowing in the cold than the 85 and they should be the same viscosity (more or less) when hot.

[MotoG5]

As a retired tribologist you are good to go. Your chosen oil easily exceeds the manufacturers specified lubricant. From a balanced preventive maintenance program perspective using products that exceed the manufactures spec can affect your costs but in this case I dont see it as an issue.   

[normzone]

Darn - I was looking forward to meeting some other folks who like tribolites.