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I was out riding tonight for the first time with my new motor off e-bay and seemed to work alright, Lastyear i had richened up my midrange by raising the needle 1 clip and am wondering if my sled sitting at 1200 at 3/4 throttle should be about right. At full throttle it almost seems as if the temp drops 50-100 degrees, the plug color seems pretty good, just wondered if this should alarm me or what because i know 1200 is getting close to the melting point of aluminum. Does this make sense to anyof you, It's on an Ski-doo citation ls 250, the motor has new bearings and gasket kit and has about 110lbs of compression didn't bother to freshen up the top end as i have another motor i want to put in its place in my basement. Should i change my needle jet back to its stock setting or is this going to cause a melt down, just wanted to toss my ideas out there before i start takin my carb apart. Any thoughts or suggestions

Thanks Guys
 

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If it's running at 1200 and you have raised the needle to make the midrange richer, lowering the needle will cause the temps to get even hotter. Lean = hot.

What color are the plugs? Can you look into the cylinder at the top of the piston and see any piston wash?

Temps are not reliable to determine if you are lean or rich; set your sled up to run right, using piston wash and/or plug color to get it running the way you want, then look at the temp gauge to see what temp that is. THEN you have a baseline to determine if things are going south... if you normally run 1200 with good piston wash and plugs are a nice cardboard brown, and all the sudden, you are seeing 1350, THEN it's time to worry.

I have an EGT on my 800. On that sled, my temps are always hotter in the midrange than they are at WOT, the extra fuel cools the cylinder and piston. I'm more worried in the midrange than at WOT. It runs around 1200-1250 as well; I think the temp you get on the gauge is very dependant on placement in the exhaust manifold...
 

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I agree with Dan completely. With the EGT you are looking for more of a CHANGE in temp, not so much a specific reading, especially since there are so many variables that can affect the temp reading. EGT is more of a monitoring tool so you can hopefully catch a problem before it does too much damage, not so much a tuning tool. Use normal tuning techniques to get it set up, and then keep a look out for differences in temp as you ride.

Hope this helps.
 
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