I had a similar experience, with hard starting in very cold temperatures, and it was caused by the chokes not functioning. The plungers were stuck closed and did not respond to the postiotn of the choke lever. I would confirm the plungers are free and working properly, and that the choke cables are properly adjusted as a first step. Another trick to try for hard starting cold sleds is to pour hot water on the carbs. Hard starting is often the result of ice crystals in the carbs blocking passages. If it starts after the hot water treatment I owuld suggest adding some Isopropyl gas line anti-freeze to the fuel to help with any water that may be in the fuel and leading to the problem in the first place. Give those things a try.

 

My buddy also has a 99 ZL600. Nice sled. Starts easy, but it too idles at 1000 - 4000 rpm at different times. Any ideas why?

 

I will give that a try, we have -15C here now so it is a perfect day to test.

 

You nailed it man! I heated up the carbs and put anti-freeze to the fuel. The sled is running fine now :thumbsup: Thanks