Suzuki 2 Strokes

Hi Guys,have I blown a head gasket? NO water leak,temperature normal,just seems to be making a funny (louder than usual) noise around 3,000rpm..cylinder block/head appears to be getting dirty (black sooty coating)around the centre cylinder block face/head & a little left & right of it,NOT a leaking exhaust port gasket...as it's a dry black dust covering,I can wipe it clean...then dirty again after 50 miles or so....I don't think it can be road grime,after such a sort run ?
Cheers,
GT750Battleship.

Just like an exhaust leak. A blown head gasket would make a motor knock considerably. It should be fairly obvious as to the sound. It would be distinctively loud. Take five minutes to perform a compression test. You can borrow a gauge. Some larger automotive stores have borrowed tool programs that a compression gauge would fall under that guideline if you don't have one of your own. Advanced Auto, Autozone, etc. One way to eliminate the exhaust port grime is to go around the gaps between the exhaust flanges and cylinder ports with Ultra Gray or Ultra Black gasket sealant. It works extremely nice, especially on these 2 stokes. Eliminates all of the oil contaminating the exterior of the front of the motor. Helps to keep it clean. If the soot still remains, you can narrow it down to the head gasket.