I;ve seen a chrome external oil cooler for sale on the Ultima Australia web site . Anyone know anything about them ? anyone using one? do they work ? or are they just a gimmick

I agree
I have a 6 row deluxe Jagg vertical mounted oil cooler on the frame down tube with a manual thermostat and it dropped the temps by 30 degrees on my bagger. The Jagg oil filter housing has a offset so the filter clears the crank sensor when using a cap type remover. Jagg also have the oil lines running under the filter so removal and re-fitting a new filter is easy. The Jagg oil coolers flow more engine oil through the cooler than the HD unit. There just released a new horizontal 10 row cooler with dual fans on a thermostat for people who get caught in city traffic jams.
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