You should run synthetic to help keep the buildup down on the valves. Do you have any older sleds you can run the other stuff in? If not I would see if the dealer will take it back and credit you towards a case of synthetic. If not, I would be buying my sled elsewhere next time. If all that fails, you should be able to sell it to a fellow cat rider that doesn't need synthetic.
Go with the Klotz Snowmobile Injector Oil. It will protect that Cat motor very well. Cat gave you a very highly tuned 700 twin, now use the oil that most high performance motor owners use. It is made for power valves and leaned out motors, which is EXACTLY what you have in an F7 with the switch on "regular". I would not fool around with anything else with such a nice engine as the F7 has.
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