If the ECM sees detonation, first it turns on the engine light in the guage cluster. If the rider doesn't see it and back off the throttle (or ignores it), "limp" mode gets activated. The only way to reset that is to shut the sled down and restart. The first assumption I'll make is that the sled has no modifications (no pipe, head or can). Typically, if "limp" mode is being activated, the sled is running substandard fuel, has fuel with ethanol added but the ethanol fuel wires aren't in the proper configuration or there is a fuel mapping problem that will require an add-on fuel controller to correct. My own 800 would regularly activate the limp mode just before the exhaust valves would open (around 6800RPM). If I blasted right through that RPM, no problem. Likewise if I stayed well below it. No flash Polaris offered would correct it and it made little difference what fuel I used in it. My only option was to add a fuel controller and that allowed me to eliminate the problem entirely.
