Hey ya'll, I hope some of you can offer some advice, qadsan, borynack, you guys out there?! Some of you may remember I picked up an 01 XR650R a month back or so and I started tearing into it at my friends shop with his help. we took off the forks and swingarm to lube and service. I am also adding a bunch of aftermarket goodies. Well today when I stopped by the shop we ran a leakdown test on the bike. I wanted to do this to see what kind of shape the engine was in. When I bought it I looked it over a bit and it appeared the bike had been well maintained. It started easy, no steam or smoke on start up, made decent, if not good power. Well when we run the leakdown it reads 12%, which in itself is not bad...BUT...we are hearing a gargaling noise when air is applied! The wise old man at the shop seems to think it is the coolant bubbling, you can allmost feel it a little in the hose that comes off the head. It is definatly there and noticeable! Does this mean a cracked head or blown head gasket!! The coolant looks fine, the oil is not milky, could it just be pushing air past the rings in teh crankcase and what we hear is oil gugrling?? The bike is an 01 that is uncorked, as far as I know it was never seriously overheated but I just dont know its whole history. I would hate to tear into the engine at this point but do not want to ride it if its screwed up! Any advice on what to do guys? I am at a loss at what to do at this point!!