M8 EGT and A/F probe question

[Slamnek]

Sled: 09 M8 162 with RK head and piston kit (15hp drop in kit) SLP exhaust Y-pipe to can, D&D fire breather intake, RK clutching, and Boondocker box. I have koso EGT and AEM A/F gauges
The last ride of the season in may at revy my sled ran great for 2 days then on the third day i was getting super high EGT temps and really lean A/F reading. I tried adjusting the BD box and that did'nt change anything except making my sled boggy as i was loading up with fuel. Mag side was reading around 200-300 degrees F so i knew that the probe was toast and the PTO side would hit 1500 just putting along and the A/F guage would not come down below 13.8 or so when it should be around 12.5. It would get up over 14 when climbing. I pulled the plugs and they did look a little too light for my liking. The sled performed really good with no hick ups or lean pops. I rode it all the way out from turtle with no problems. could this just be a probe issue? Thanks for any input.

 

[Got boost want snow]

Imho I think it is the sensor as you rode at altitude for 2 days before with no problems, to check your O2 sensor pull it out of the pipe and wrap it in a gas soaked rag it should give a rich reading if not the O2 is toast. My Tapex did the same thing when we were on boulder in May but I had rode all day and not a problem. When I got home replaced O2 and all is good. I realize 2 strokes are more sensitive to lean conditions.