I acknowledge that it may be a flywheel issue, if you are trying to run it with a light flywheel and with no drive to the blade plates. B&S warn us against doing that, and it seems the obvious cause of the problem you are having. Is it the wrong engine for the mower (i.e. one that is made for a direct drive push-type mower, and hence has a light flywheel, but you are running it on a ride-on, which starts with the blade plates declutched)?

Last edited by grumpy; 09/03/10 01:17 PM.