I’ve not been happy with my Shinko 244’s. It’s been less than 2000 miles, and I’ve lost several center knobs. See pictures below showing three missing center knobbies. I’ve now counted 6 lost knobs in all.
There is also a discussion on SBR here and I can find tons of links online pointing to problems with Shinko’s. I’m going to take this up with motorcycle superstore (where I bought the tires), but more importantly, I’m staying away from Shinko’s.