Kz750(4) O-ring replacement

Good afternoon all, it’s been a while since I posted here but the bike is doing really well. I’ve been riding to work every day and it’s never given any issues whatsoever. 

I left it parked over the weekend and it’s got more than a few drips of oil on the ground. Not like a puddle but not a drop or two. I trace it up and it’s leaking off the secondary shaft bearing cover bolt. I’ve never removed it but the manual says the seal is an Oring. I found the Oring on Z1 and matched the size to a local Napa one I got for $0.59. My question is wether or not the bike will dump oil when I remove this cover with it on the kickstand? I have the center stand temporarily removed so I can toss it on the bike for this repair if it will prevent the bike dumping oil on the driveway. 

The Secondary Shaft bearing cover is on the same side of kick stand, therefore most likely there would be some leaking......unless somehow, you almost lay it flat on the other side.


............but what is the big deal about emptying the oil???  It never hurts new oil, as the engine uses plain bearings,....... but if it means that much to you, if it is still clean enough you can always pour it back in.

I replaced that secondary shaft cover  O ring a few years ago. You will lose a little oil. Not a big dump. If you can tip the bike to the right you may not lose any. IIRC I did mine with bike on centre stand on a small cheap tarp with oil collection tray underneath. Swaping the O ring out is a pretty quick job. 

I’ll end up doing it on the center stand then. The issue with new oil is that it was changed 2-300 miles ago. It’s brand new oil already. If the Oring ends up working as a replacement I’ll post the part number here for others with the disclaimed it isn’t an OEM Oring. 

I think 
Dont remember exactly that i may have measured height from ground level to oil window and ground level to 2ndary shaft cover and didnt see much difference
 

So far so good, the replacement was about 30-45 minutes and that’s ONLY because these lovely JIS screws. One I was able to get out using needle nose vise grips and the other I just couldn’t get a hold on so it had to be dremeled and flat headed out. Rode it for 10-15 minutes and no major leak so far. Now the overnight test is where we really see the truth. As to if it was a successful repair or not. 
This is the leak after sitting for exactly 15.5 hours. 

 
This paper coffee cup was filled up 2 times by the oil leaking out. The level was checked just  yesterday on the center stand so it was a good fill. Probably 16 ounces each so 32 OZ of oil would have leaked. 


I’m going to hold off on posting the Oring part number before the overnight test. I don’t want to put it out there as a good solution and it not work. 

Pardon me for asking but that oil changed 2-300 miles ago? 

My apologies Dave, I checked again and it was actually 1300 miles ago. It gets confusing when you have to do 2 bikes, my truck, the wife’s car, and other machinery around the property. 

The Oring is working great. I left it for 48 hours over the weekend and it never spilt a drop! The Oring is Mahle part number #72224. I got mine from my local Advance Auto parts for $1.49 next day.