Is it ok to tip over a riding lawnmower?

It is ok to tip the mower over if you need to wash the mower deck of change the blades, however if you do let it sit for half an hour after you right it to let any oil that may have seeped into the cyclinder to move back into the sump. Also these machines can be very heavy so ensure you get help and use proper lifting techniques so you do not injure your self in the process.