Yes.... old thread, but what the heck. Someone else may be able to use the info!
I own several spare sleds for family and friends.
One is a 2011 800 E-tech FreeRide..... another is a 2012 800 E-tech Summit X.
Both of these have the factory reverse!
It is initiated by the start button (of which disconnects from the starter motor while the engine is operating).
As I understand it...... the engine rotation is reversed via the ignition electronics momentarily stalling the engine.
While the engine is momentarily stalled, the computer then throws something like 54 degrees advance at it, of which causes the engine to reverse it's rotation.
Once reversed, the spark advance returns to what would be considered normal (via a second triggering system) ...... and the engine continues to operate in reverse rotation.
Hit the start button again, the cycle repeats itself, and the engine returns to the normal rotation.
Most any piston port/reed valve 2 stroke engine can be made to operated in reverse rotation.
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