After warm up will not idle dies at every stop

If the bike is equipped with a carburator, you could simply raise the idle speed a bit. Look at the top of the carb and you'll see a large round looking cover. On the right side of this cover, there is a small screw. This is the idle stop screw and it sets the idle speed of the engine. With the engine at full operating temperature, set the idle speed at 1000 rpm or so. Turning the screw clockwise increases the idle speed.

If you engine is fuel injected, you'll have to take the bike to a repair shop to have the idle speed adjusted.

Good Luck, Steve