Questions about coolant temps on a recent install of Mpi/Yamaha 180 supercharger.

[jgustman]

What is everyone else seeing on their Mpi 180 s/c kits? Seems it’s the low speed deep snow breaking trail that really spikes the temps. Hit 208 deg and the stock over temp light came on. Light throttle on packed or little snow and temps drop the the mid 180’s, get over 50 mph and the temps drop from mid 190’s to the 180’s as well... Frustrating that the 35-50 mph range is where it seems hottest. Instructions say no full throttle operation over 200 deg...right when you need it the most breaking trail and it’s quickly over 200. Hell, I would never get to do any extended full throttle runs if thats the case if I follow the instructions noted below. Once it get warmed up it never gets below mid 180’s at best trail riding...The cooling system been fully bled and re-bled several times and yes it has an additional tunnel cooler. Runs great, but mileage doesn’t get any better than 10.5 mpg. Calling Ulmer Racing tomorrow and see what he says...
Here is the line from the install instructions below..
3. We also HIGHLY RECOMMEND A WATER TEMP GAUGE. We recommend a water temp less than 180F during periods of extended full throttle riding. You should never operate the vehicle at aggressive throttle; positions with water temperatures above 200F. A Low temperature thermostat is available from your dealer / MPI.

On a side note I also just installed an Ulmer Racing clutch kit and vents in the nose below the headlight and one in the cowl between the speedometer and handle bars. I am wondering if the cool air is bypassing the radiator now and just vents out the top cowling instead of getting pushed through the radiator?...Last spring when I installed the supercharger, no extra vents and saw the coolant temps drop into the low 170’s when I hit soft snow and supplied clutch weight kit, not anymore....

 

[74Nitro]

I had the mountain exchanger added, never had overheating.

 

[kviper]

My turbo Nytro was overheating and long story short it ended up being a bad thermostat.

 

[jgustman]

Update: I re-bled several times with no success, still running hot. I did have an air lock, I had to hoist the left ski up and compressed the rear suspension, fired it up again”already up to thermostat open temp and the radiator cap off. I saw the coolant level drop about 2-3 inches from full. No more issues, runs in the low 170’s-high 180’s now, where before it was running 187-208...