As this is likely a 4 cycle B&S engine, 30W for summer use will work fine,
while 10W-30 is better for colder weather. There are 2 cycles, such as
motorcycles that do have a crankcase which requires oil changes as well as
require a fuel/oil mix.
"Scudo" wrote in message
o.uk...
Have had lawn mower for a year now and going to change oil, its a briggs &
stratton machine, 2 stroke. What type of oil do I use as I have plenty of
20/50 that I use for motorbikes, should I use a special one for the mower?

thanks