Working with heat transfer. Something I observed is bikes with crotch coolers. Interesting people install them and comment it helps keep your leg and body cooler. Cylinder still create same amount of heat so where did heat go......... It's in the cylinder. Crotch cooler slowes air flow therefore heat transfer. Remember rear cylinder air. Temp already raised by front cylinder therefore slowed transfer to 2nd. Cylinder. Newer cylinder deactivation only occurs at low air flow or idle.