I think mazz 60mm longstroke cranke broke my inlet port...please help!

hi anyone’s expert advise is very much appreciated ,just installed a 60mm longstroke mazz crank with all the necessary gaskets and had a mild test run and after few minutes it went on bogging and runs very poorly,its sound like a loose compression engine cant go more than 20kms/hr,check the plug,so oily,when i took off the block i found out scratches marks on the crank and its on the inlet port side,im so worried it damage the inlet port of the case and thinking its the cause of the blowby because it had leak,would that be the possible cause? if not what could be the other cause of the problem? please i need your advise…many thanks.

set up
-210 malossi
-match ported crankcase
-jim lomas left hand pipe
-24mm stock carb 130 main jet
-cyl head 69-d sip
-reinforced clutch basket
-and the newly installed mazz 60mm longstroke