This treadmill (I bought thinking it has a 5.0 hp motor) has a 4.5 hp motor. I found 3 ads, same treadmill all with different motor horsepower. I opened up the unit and the motor had no horsepower listed ( motors made in USA have the hp on the unit, CHINA DOES NOT LIST HP). I copied down all the manufacturers amp/serial number, used a Chinese guide book and found my motor is 4.5hp even though I bought a 5.0 hp. The same company sells 5.1 hp (higher price) bottom line is the average customer won't do the research I did. The increase hp also means the cost of the treadmill is more. I weigh 190lbs, I wanted a 5.0 hp but got a 4.5hp. Works good, so far. I bought the extended warranty just in case. Shame on sellers, knowing the motor cannot be identified, selling it at any hp to make more money!!! 3 stars for lying about the hp.