I'd go through the carbs again just because. Its not about the miles you've put on since you cleaned em its more about the time it sat over the summer without flowing fuel. The gas varnishes and plugs orifices
Then when they are out you can better reach the bottom steering post greasert too. Other greaserts on ski mount bolt, on the spindle, rear suspension upper and lower front arm, and the rear scissor assembly there should be three or better. A couple more behind the secondary and down on the speedo pickup
Fuel filters are pretty cheap too
I'd check belt alignment from a gernaded belt, you may have a bad motor mount