If I missed a sticky I appologize but how interchagable are the rear wheels on these bikes? Can I just buy a complete rear 18" wheel off a different kz650 and pop it on my 81 650csr? I see them on eBay with the drum for older models.. I'm going to cafe it and am working out the details. Currently getting the bike working in stock form and will ride as is this summer to see how it goes.