WalkingMan,
Look at the pic that RL posted. Notice that the butt of the knife (not the ring) tapers before it reaches the ring? And by tapers, I mean in the eidth wise direction (not thickness, I am talkign about height, the view we can see!) Those dips act as brakes as you spin the knife. The knif can be helt in a reverse grip edge down (RL's second pic) and then spun forward to get an extended position (RL's third pic). Withotu those brakes, the spine of the knife can crunch your finger. With those brakes, everything is cozy
On a side note, the last pic is what most folks think of as a standard knife grip, but for the most part the karambit is held in the other 2 grips. You don't spin the karambit into the saber grip. In fact, I know of no spinning that is done when holding the knife in the forward saber grip. All (most?) of the spinning is done from reverse to extended.
PhoulPlae: Those "serrations", IIRC, are called barbs and they are used for tearing. This Strider/Tarani karambit is double edged as well. Karambits can be found with or withour barbs, single edged, double edged, etc. There are actually a lot of different techniques you can easily do with the karambit, including chopping motions, scraping motions, grinding back and forth with the barbs, etc.
