i know on my 06' 800 at 210 f is when the fan kicks on and off at 190 so there isnt much room for overheating that is for sure.

 

Koerbs:

It started to overheat and flash HOT while going up a rocky hill, there was about 10 quads right behind me (poker run), so I "limped" it up the hill and hoped I could coast down the other side toward the truck. While going down the hill is when it started to overflow. I stopped as soon as I could get the heck out of the way. I didn't want to leave anyone hanging on the hill.

 

The limp mode is only in case of a sensor failure or a wiring problem that does not allow the sensor to communicate with the computer.If that happens the computer will use a default setting to keep the engine running.

 

"Limp mode" is a broad non technical term. Many EFI ECMs are programmed to protect the machine from damage due to several conditions such as oveheating conditions,excessive leaness, high inlet air temps (on factory supercharged/turbo vehicles) ect..so while a faulty sensor can trigger default operation to allow the machine to limp home there are other instances when the ECM will modify paramters(timing,fuel,RPMect) in an attemp to prevent damage..both are generally considered limp mode.

The 850XP hot lamp blinks at 257*F,at 266*F the lamp becomes steady and the engine will missfire above idle..this is a form of "limp mode"..