he importance of cool oil in an air-cooled engine is no secret. Air-cooled engines are also oil-cooled, and to a large degree cool oil pays dividends everywhere you look. Engine longevity is increased, performance is enhanced and there are noticeable gains in everything from horsepower to fuel mileage. Putting an oil cooler on a Harley just might be the smartest move a rider can make.
     But just cooling that oil isn’t enough. Everything gained with the addition of an oil cooler can be negated if that cooler is also causing a pressure drop that hinders the flow and delivery of cool oil to everything in the engine that needs it. That’s where the Jagg Oil Coolers come in. It’s Jagg’s philosophy to provide quality oil coolers with an engineered balance between cooling and oil flow–one just as important as the other. The Jagg Oil Cooler–and there are applications for every Harley on the road–achieve that maximum cooling effectiveness with less restriction and pressure-drop than its nearest competitor. Significantly less.
     While most oil coolers, Jagg’s included, will lower the oil temperatures anywhere from 15- to 25-degrees depending on the flow rate, the Gallons Per Minute (GPM), the real difference shows up when you start looking at those GPM flow rates and the pressure drop across the cooler. At a moderate flow, say 0.750 GPM, the second-best cooler on the market registers a 2.5 PSI drop while the Jagg number is just 1.0 PSI. Not much difference, you say? Raise the RPM a little and take another look. At 1.5 GPM lesser coolers can drop the pressure by 5.0 PSI, the Jagg by only 2.0. Now grab a big handful of throttle and raise the flow rate to 2.5 GPM. It’s not uncommon here to see a 10.0 PSI drop in some coolers–with the Jagg holding steady at just 3.0. There’s a real difference here, and it counts. Cooling and flow go hand-in-hand.
     Oil coolers are important. It’s just as important to bolt on a good one. Every Jagg Oil Cooler takes the engineered “systems approach” to performance, balancing cooling with flow. Drag Specialties has them all.