Hi everyone I am new on here and a new z400 owner. I am building a z400 for my son to race in NYC for 2022 season. I was wanting to know 1st of the cylinder has BDFAG stamped on the right side of the cylinder I was wondering if it may be a big bore cylinder? I don't want to take the off lead off to check and can't seem to find any info it is factory stamped into it. Any info would be great.