My K5 finally developed the tach drive seal leak issue. I was amazed at how much oil leaked. Since my budget is extremely fixed, I use my bike as a daily rider and I am a cheap bastard I wanted to wait until I saved up enough for a bulk order of several items from DSS. I noted the seal size was 4.8 x 14.5 so as a TEMPORARY fix I cut a washer out of tire patch rubber 3/16 x 1/2 with hollow punches, cleaned the face of the existing seal, applied a small amount of rubber cement and pressed the homemade washer against the face of the old seal. I then slid a 4.8 ID oring over the tach drive shaft and reinstalled the cable. Three days riding and no leaks. Not a "purist" fix but not bad Hillbilly engineering to keep you riding and your engine clean TEMPORARILY!