Topic: '72 CB500 clutch issues/oil leaking into left crank case

[meggymilly]

Hey there!

Had a few issues that I need some assistance on for 1972 CB500. At this point I have pretty much did a whole rebuild on the bike. It runs great, but I have two issues (and I wonder if they are connected at all):

-Issue 1: Oil is leaking into my left crank case. After a ride I notice that there is a little puddle of oil sitting in the crank case and I take it apart. Could it be a bad oil pump??

-Issue 2: Within the first moments of riding, my cb runs great, but after awhile (when it starts to get pretty hot) the bike dies and will not idle at all. I replaced the clutch push rod and have also replaced the old springs with new ones, but they are pretty stiff and I don't know if I need to get stock springs (it's hard to shift — mostly down shift — and it's impossible to get it in neutral). I feel like it definitely has to do with my clutch.

Any help would be greatly appreciated!!! Thanks!! 

[Scott S]

 One of the biggest culprits of oil under the sprocket cover is the oil pressure switch. Start by removing the cover, cleaning it up and then run the bike again to see just where it's leaking. There are a couple of seals behind there too, but start with the oil pressure switch. Some people dust a little baby powder on the clean engine to make the leak more obvious.

 Show us how you're using the choke. It's very easy to get the 500/550 choke operation backwards. That could be why it's dying after warming up.

[calj737]

I'd suspect ignition issues for the dying when hot. Check the resistance of your plug caps, your coils, and you might need to change your condensers to remedy this issue. I doubt it is clutch related. The stiff clutch is likely due to a poorly adjusted cable, or a cable in need of replacement.