For the benefit of the collective, I decided to make some actual comparisons of counter sprockets.  Here are 3 options side by side for easy evaluation:

 

 

 

 

The stock OEM 13 tooth is in the middle.  On the left is a JT 12 tooth.  On the right is a Sidewinder Ti-2 (13 tooth titanium).

 

Here are a couple of shots of them all stacked on top of each other:

 

 

 

 

 

 

And finally, a head to head of the Stock vs. Titanium Sidewinder:

 

 

 

Conclusions:  There's really not that much difference in size and shape of these three sprockets (besides 13 tooth vs. 12 tooth count).  Tooth length and spacing was very similar.  Tooth width was about same for Stock vs. JT, while the Ti-2 is a little thicker (wider) in the tooth.  

 

These aftermarket counter sprockets are definitely not a lot deeper (taller teeth) than the stock unit.  I found that interesting....relative to past debate.  It always bothers me when people make claims regarding products (or OEM parts), yet never post any factual information backed by photographs &/or measurements.  I mean, it is what it is....so get dirty, dig into the nitty gritty, and post up your findings!  That ain't so hard.  Just saying...

 

I have over 2,000 miles on this stock 13 tooth CS at the time these photos were taken.  It does not show any significant wear at all.  I'll admit, I'm not very crazy about those plastic balancers on the stock counter sprocket.  That just looks like a potential trouble spot to me....for someone who doesn't keep there countersprocket real clean.  But what do I know?  I'm not sure what purposed these plastic thingys were designed for.

 

I think the Stock counter sprocket is going to work just fine if you maintain proper chain tension and keep your adjusters and axle nut locked down tight.  The little adjusters don't like to stay locked very well.  Consequently, they can loosen while you ride and let the axle move....making your sprockets (& chain) go out of alignment.  Especially when you ride in rocky terrain.

 

I minimized this potential problem by changing my chain tension adjuster locknuts to actual "nylocks".  

 

I purchased the nylon locknuts in Metric M8 x 1.25 pitch, and then threaded them on backwards.  Now, I can cinch down firmly (without massive force) to my swingarm and the tensioner bolts aren't moving one teeny weeny bit!  Its a little more tedious to work with, but a whole lot more secure.  And no more cheap locknuts frozen to the swingarm....due to overtightening.  I can even use "antiseize lubricant" on the tensioner bolt now.

 

HF