I got Shinko 712's to replace my ancient original stock tires on my '86.  I've put a little more than a hundred miles on them so far and thought I'd offer up a review.  I went with the standard size for the front and a 140/90-15 on the rear.

After hearing how slick new tires can be, I was a bit nervous taking her out which probably made me a bit hypersensitive to the changed profile of the rear tire.  The stock IRC has a flatter profile compared to the entirely round Shinko.  The first couple of turns really felt like the bike was tipping quite a bit.  I quickly got used to it though.  The new tires were definitely stiffer than the old worn out rubber I had, and I noticed a huge change in the ride & handling of the bike - much crisper with better grip in the turns.  The downside is a bit more vibration communicating to the handlebars and bumps to my tailbone, but I'll take that in exchange for the overall improvement.  It even feels like the bike is accelerating a bit faster.  

I'll have to see how they wear, but as of right now I'd offer up a very positive review of the Shinko's.  Good grip, handling and performance.  And they look good, too.  

I got them from Motorcycle Superstore for about $100 with free ground shipping.  BikeBandit had a slightly better price but charged for shipping.  I had a local shop mount them for me for $75, but pulled them myself in my apartment parking lot with a car jack and a cinder-block - that was a real treat.  

Thanks again to all who helped me figure out that I needed new rubber.

Those are the EXACT same tires I put on my 05 back last fall. I was also impressed with the improvement over the stock IRC tires. I've still only got about 400 miles or so on them and they feel great! Only wear issue I've had so far is I added saddlebag brackets over the winter and I've got the brake side rubbing occasionally, but I noticed that one of the bolts holding the rear fender on the frame is missing causing some flex/twist in the rear fender. Once I get a replacement bolt in there I think I should be free and clear again.

I put a set of the Shinko 230 "tourmasters" on my wife's bike and I have nothing but positive things to say about them- plenty of traction, responsive, good comfort, excellent price. I also run  Shinkos on my GSXR and I have never had any traction problems or quality issues on them either (and I run that bike hard). As far as performance/$$$ I think you'd be hard pressed to find a better tire out there.