Loud clang while cranking

I just got my 79 KZ750 twin that had been sitting for years (sort of) running and am concerned about a sound it sometimes makes while cranking. Sometimes while cranking with the starter, there will be a very loud metallic clang or series of clangs and the crank (as seen by the ignition timing) will stop moving while the starter continues spinning. I noticed that this never happens if I am just turning the engine over with the spark plugs out, so I was guessing a gear or chain might be jumping teeth when under load. Any ideas what it could be?

Unfortunately the screws for the engine covers are somewhat rusty and stripped, so opening it up and looking for broken bits isn't really an option. Other things I know are wrong with the bike so far are clutch not full disengaging, carbs looked clean but may need a touchup and tuning, and when running, it often stalls if I turn the choke off or give it gas. As far as I can tell, the ignition timing looks correct.

Your starter clutch is toast. If you bump start it you don't hear any such noises do you?

Bill

Thanks Bill. I guess that means I need to figure some way to remove the rusty, stripped bolts holding that cover on.

Maybe the mechanical timing advance unit is stuck in the fully advanced position, that will give you some ugly noises while the starter is cranking

MatthewakaMatt wrote: Thanks Bill. I guess that means I need to figure some way to remove the rusty, stripped bolts holding that cover on.

You can drill them out carefully. The repair is not difficult as long as the boss on the starter sprocket is not too worn.

Have you tried to bump start it?

Bill

You can cut a slot in the bolt heads with a dremel tool, then use a large screwdriver/impact driver to torque them out.

They may break regardless of what you do, so having a drill and some reverse thread bits at hand is recommended.

Good luck.

TeK9iNe wrote: You can cut a slot in the bolt heads with a dremel tool, then use a large screwdriver/impact driver to torque them out.

They may break regardless of what you do, so having a drill and some reverse thread bits at hand is recommended.

Good luck.

I'd not suggest that option. I just went out and looked at my 79 750 twin and all the screws are recessed. It would take an artist or Mr. Emmuanel Goldstein to accomplish that task without narfing up the case in the process. Select a drill bit bigger than the screw diameter but smaller than the head diameter and drill carefully. Once the head spins you can take off the case and use a vicegrip on the remaining studs.

Course it all depends on the actual condition of the screw heads. Before I did anything I'd try an impact driver, they've never failed me except in the worst of circumstances.


Bill

To avoid stripping more screws try grinding the pointy tip off of a #2 phillips bits. the screws are different from a regular phillips (JIS), and the pointy tip keeps the screwdriver bit from fully seating inside the screw.

Fortunately this is one of the only times drilling and using an reverse thread taps actually worked for me. I got all the screws out and will replace them all with new hardware.

At this point I guess I'll just order the parts and that specialty tool to get the clutch off and hope . Oh, and since the clutch isn't working yet (next on the to do list), I haven't been able to try kick starting it.

mjg15 wrote: To avoid stripping more screws try grinding the pointy tip off of a #2 phillips bits. the screws are different from a regular phillips (JIS), and the pointy tip keeps the screwdriver bit from fully seating inside the screw.

Grinding the tips is the only way to make Phililps screwdriver bits match the JIS (Japanese Industrial Standard) Kawasaki screws. I use a ground DeWalt #3 on the 6 mm case screws and a ground DeWalt #2 on the other smaller screws. They will not damage the screws when properly fitted. Just take your time grinding them until they will stick in the screws and not fall out.

One more question about fixing this. Where can I find the gasket for that side engine cover? Online I've only found complete engine gasket sets, and never just that individual gasket.

You can use a liquid gasket maker just fine. Apply a very thin film with your finger to both very clean surfaces, then assemble as per the directions on your choice gasket maker.

The regular black stuff works fine.