Riding lawn mower will turn over but not start

Riding lawn mower will turn over but not start

I'd replace the starter solenoid the battery I've clean the carburetor I checked the fuel shut off and it works I change the spark plug I have fuel going to the carburetor still it turns over but will not start it's a Scott's 17 horsepower not sure what else to do please help and I also bypass the safety switch just to make sure that wasn't it