ok i have a600 srx ...running like crap....i took the pipes off to clean and when i tipped the pipes fuel ran out...all so back firing like every 30 seconds..
1. Have you clean the carbs yet this season?
2. Checked and set the floats, needle and seat?
3. Change plugs?
4. Checked the wires?
5. Ohmed out the plug caps? ( should be 5k ohms )
6. Put fresh fuel in the tank?
These are the things I would look at. Keep us posted
backfiring at idle, indicates lean pilot circuit. check and clean the pilot jets and pilot circuit. if the sled just came out of storage, this is most likely the issue.