Hello guys and girls, I am new to the site and I am a Kawasaki cyclist owning a 2006 Kawasaki Vulcan 2000 and a 2006 Kawasaki EX250 Ninja (250R). I recently purchased my Ninja and after trial and error and 2 carbs later, I realized that I have either a cracked head or a blown head gasket. The bike was running well, despite this (in idle) and I rode the bike a couple times only to realize that there is no power leaving out of 1st trying to up shift into 2nd. After the last attempt to ride and sitting in idle, I noticed antifreeze dripping from a weep hold in the exhaust. The oil also had the tale tell sign of water being in the oil. I have a second motor available that I'm thinking about swapping out and the owner assures me that the engine only has about 3 miles on it and it appears to be in good shape; however, the top mount is wider and there are a few differences in the head i.e. the exhaust flanges and the timing chain tensioner sticks out rearward (horizontally) oppose to vertical one on the original motor. The top valve cover also has a case vent hole attachment with a hose attached; so, I coded the potential block out to a 2008 - 2012 250R using the block ID number. Does anyone have any suggestions or thoughts or willing to shed a little light on my predicament???