I have Dakota Digital gauges that give me exact cylinder head temperature.

Just did a 124 kit and I'm running anywhere from 310 to 340.

I'm not too worried about the heat on my legs because I can deal with that, I'm just concerned about what the danger zone of high temp is. I am not sure when I need to start getting worried about the motor overheating.

 

Did you do the build or an indy?

If you did the build, who did you buy the kit from and maybe they can answer your question regarding head temps being too high or not?

 

don't these engines have some sort of excess heat detection sensor and go into limp/protection mode if necessary?

 

Yes, they do. Aftermarket tuners may deal with temperature differently though. So one should always be aware of how their tuner deals with over heating. I’m using a T-max. Unlike Harley, where they automatically shut down the rear cylinder (EITMS), T-Max keeps the rear cylinder running, lowers the idle and adds more fuel to lower the temperature. It will also trigger the check engine light letting you know to either get some wind over the fins or shut the bike down before any type of engine failure occurs.

 

I also have a 124 kit and Dakota gauge on my 2017 RK. My head temp regularly gets to 340-350 and has been as high as 380. I am considering adding the Dakota optional oil temp sensor to give a better idea of heat. I am wondering if I am over worried or should I look at options to cool it down?

 

I haven't gotten past 340. I think I'm okay.

I do have the oil temp sensor installed and it gets to about 200 or so max.

 

I also have the Dakota gauges with the oil temp on a stage iv, 114, with fan assisted oil cooler. I have disabled the EITMS (with builders consent) since it is based on ambient temps as much as anything, and I didn't observe a cooling effect. Head sensor is in the rear head only, oil is a sensor in the drain plug. Here are some observed temps at the higher end:

95+ deg air, slow speeds, stop and go Head 350-380, Oil 175 -200
95+ deg air, steady speeds 55+, Head 350-380, oil 140-145

Avg temps and riding conditions, head pretty steady at 330-335, oil 130-135.
Avg temps and hard riding, head 350-370, oil 140-170

Added Love Jugs, lowers head temp while not in motion, stop and go. Watched it drop as much as 15 deg, but no change while moving.
Head has been 400, oil 205.

 

Thank you. Your info is helpful.

 

While, not a big bore, my stage 2 117 head temp will hang in the 368-384 every time I have the stock lowers installed. With them off, the head temp stays in the 320-336 range. It doesn’t matter if the temps are in the 60’s or in the 80’s (today).

 

wow, that's a huge diff, those lowers really block the airflow to the engine..yikes