Just bought a Lazer Z 27/60. I love the mower but the ride it gives is rough compared to my LZHP52 and my 97 Lazer Z 25/60. This new mower has new no air front tires and lower profile rear tires. Would this cause a poor ride ? Does the ROPS change the ride? What can I change to take the back ache out of this mower? The rear tires had 23lbs when I got it and i changed them to 13lbs. It helped but this rides rough. I dont want to purchase a new seat as I think a newer mower should be better in all respects and not need immediate and costly upgrades to ride better than seven year old mower. Any one else have a problem like this?