engine knocking

I see this has been posted before, so I will ask just a tiny tiny tiny question. I start my bike up and it runs OK. I ride it for ten minutes or so and as I pull back up my driveway, there is a hard knocking going on and the engine dies. I have read that it may be the cam, clutch, or other reasons. Do my symptoms give any hints to where it is coming from?
Thanks

Sounds like its getting hot. Check your oil level, jetting and oil pressure.

If a KZ is running rough enough to stall,it will rattle just before it quits.Clean the carbs,give it a tune up.
It just might run good and not rattle anymore.

The cam or the clutch would present as problems soon after the bike was up to temp. Is that the case? If the ignition or carburation's off they can make the engine lurch which can make the cam chain slap which you may well describe as knocking.

FIRST thing to check. Is the gas tank air vent clogged? Before you pull into the driveway open the gas tank. If the problem abates your gas cap vent is clogged.

kzcsi

Some additional thoughts --

Would check ignition timing with strobe light and verify advancer unit is working properly and not stuck in idle position. Remove, inspect, clean and lube, if necessary

Also, adjust cam chain (routine maintenance item per owner's manual).

Also, check valve clearances (might be too tight) and adjust if needed.

Also, double-check that oil does not have any gas odor (to assure no fuel intrusion into crankcase contaminating and diluting the oil).

Good Luck!

Ooooh, that was what I was wondering. I have the dyna-s ignition. Is the advancer mechanical like it was with the points, or is it integrated in the circuitry?

The OEM mechanical advance is installed on your bike as the Dyna S has no other way to advance the ignition. You got lots of advice... Most of it revolved around general "you should tune the bike up" stuff. I honestly am kind of puzzled by this posting. Your bike has a roller bearing crank and the rods don't come off... never heard of one of these things clunking. The cams do not clunk nor do the valves and the crank primary is directly gear driven so again, I can't think how they could clunk... only thing I can think of doesn't make sense since it would clunk even with the engine cold... timing chain. The timing chain CAN be slapping. FIRST thing I would do is to adjust the chain as I am pretty sure by your general comments you probably haven't done this. Do you have a manual? It takes about 2 minutes to adjust the chain tension via the tensioner located at the rear of the cylinder block. Essentially, this is a spring loaded rod. Put the bike at TDC.. that is top dead center by first removing your spark plugs and feeling that the #4 piston (right most as you sit on the bike) is UP. You can stick your pinky in the plug hole or a pencil or something. Anyway, now get over on the left side of the bike and look at the tensioner. It is the metal body that sticks out of the block about 4" and is held in place by two 6mm bolts. Note that coming straight out at you is a 6mm bolt with a locknut. This bolt/locknut hold the tensioner rod I spoke of earlier from moving so loosen the locknut. Then back the 6mm bolt out a few turns. Now go over to the other side of your bike and remove the timing/points cover. USE A 17MM SOCKET ON A SOCKET WRENCH and turn the 17mm nut on the end of the crankshaft and NOT the smaller one. If you failed to remove all four plugs, you won't turn the engine over easily, if at all. OK, turn the crank 360 degrees so you will be back at TDC again. Now go back to the other side of the bike and tight the 6mm bolt to hold the tensioning rod and then the locknut. That is all that there is to it. If you still have the clunky sound, you will have to pull off the valve cover and LOOK at the cam chain. There may be something broken that guides the cam chain or the chain is badly stretched but we will cross that issue when and if we get to it. BTW: Do all the other tune up stuff because I am SURE your bike is in need...

Thanks y'all. It is getting closer and closer. I'll keep plugging away at this stuff.

does it die when you go up a hill, like it bogs out kinda dying?

it could be that you have a vaccume leak and that the hard load of the hill drops your engine rpm causing your clutch to jiggle and shake therfor stalling the engine.

try starting it up and right away drive it up a hill.