C15 oil

[TIGERJ]

Now engine has run a few hundred miles thinking about oil change.
So probably use 20/50 again ?
Also
I think I read in Rupert Ratio gear box oil recommend 90s grade
Anyone used this.
Regards
          Tim

[om15]

I use 50 grade in both engine and gearbox with no problems, interested to see if this is normal practice