Ran it many years on multiple sleds, I can tell you thought the number one factor for keeping the motor running,
Get some koso dual fast prob egts, install them with the sled stock, go out and hold it wot for as long as possible and record temps, 15seconds plus. Usually they will run 1150-1160* WOT and hold.
at 6-6200 rpm it will run around 1260*, those are the 2 spots that are major for tuning but pay attention for a few rides.
Then when it comes to tuning just make it do the same but the mid range is always risky on a mod 1000, most of us just vary the throttle to keep it cool because you can't tune it out. If you add fuel at 6000rpm the exhaust temp sensor will pull the fuel you put in and lean it out and cause major tunning issues. But with know before what your temps are is how the factory ecu is programmed and the closer you match it the stronger the 1000 runs.
I tried running wot around 1250 and couldn't pull a hill, Once I got the temp to hold around 1160 I pulled the hill with skis up. This is by far the number one setup on 1000's and I wouldn't own one with anything less than this setup.
I also ran a fuel pressure regulator and had gains.
I can walk you through this on the phone if you would like to set that up
