I am definately a fan of the Z1 and KZ Kawasaki. Probably the last best practically indestructible aircooled inline 4 ever made. Without opening the motor of a KZ1000 you can coax 125 horses out of it and that's without boost or NOS. Under boost you can pretty easily make 200, but more than that and you better crack the case and weld the crank and put some good pistons swinging on those stock rods. Now you can make in excess of 300 HP and put it on a slick and run in the 8's or go 200 miles an hour and still ride it around on the streets. This from a motor designed in the 70's!!! What more can you ask for, by the way, that stock clutch will hang in there through all that too along with the tranny. So now what? Step it up to 1500 and put her on race gas and go top fuel racing, now what other motor with a factory case and head can you do all that with? NONE! That's why I LOVE KZ'S.