There is a pipe behind the #3 cylinder on the engine case that has the oil pressure light switch. On a bike with an oil cooler, The pipe comes up out of the engine and gaskets around two holes via orings. On a bike with an oil cooler, there is a double outlet fitting that is installed in place of the OEM oil pipe. This fitting will generally have two male barbs so oil can flow and return. You stick hoses on the barbs for oil flow to and from the oil cooler. You use hose clamps to secure the hoses. Most folks will use rubber hoses under the tank but those with more aesthetic sense will use stainless hose run along the side of the bike which looks pretty trick. I don't recall if the J motor has the same OEM pipe set up as does the older KZ family (KZ900/1000/Z1) so don't know for sure if an older oil cooler pipe replacment piece will fit on your bike... Where are you fitting the outlet pipe? Is there a plug on the side of the J motor as there is on the older engine cases?
wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
