One of my Bunton mowers has this problem I cant seem to get rid of. It's obviously a walk-behind and one side seems to be ok as far as pulling it's own weight but, the other side(my right side) is awful. I have changed belts $50.00 a side-Ouch! and no better! The other thing is it never feels like it has the strength of my other walk-behinds as far as going up inclines. I don't know what else to do! Some days it doesn't even have enought to get up the trailer. What am I not thinking to do here?