Okay as some of you may know from my other thread, i have been having a on going issue with my Next gen lazer not having enough power when bagging. The motor looses power in thick grass and while going up the slightest grade. I started out with a 52" 23 kohler Next gen Lazer Z advantage series X. Then Exmark was gonna get me a new mower, but we decided to get the regular Lazer Z 52 with the 27HP Kohler. We still have the same problem with this new mower. When u take the ultra vac off the problem is gone. I was wondering if the new pump system is robbing too much power and i have told this to my dealer. Second i compared the engine spec's of the 27hp kohler and the 24hp kawi that exmark offers for the Lazer Z 52's. The kawi is pretty much equal in torque and c.u.'s. I know Toro offers a 23hp and 27hp Kawi as well as a 23, 25 and 27 hp kohler for the're 52's. My dealer has been in contact with Kohler. Kohler wants them to do a leak down test and vacum test on the mower. I think they wont find anything wrong. I wanna know how many of you guys have a Next Gen Lazer 52 or a Toro G3 52" with the Ultra vac?