'79 Kawasaki KZ400 - What should I do?

[@garyhannan4682]

Flushing the engine, helicoil the sump hole, cleaning up the timing advance shaft etc are all logical and relatively easy steps for someone with your kit and experience. KZ 400 was made in the States, so I would expect plentiful parts 2nd hand, or try Z1 Enterprises. I think some parts were shared with the Z750 twin aswell so that's in your favour. It's an everyday middleweight, never going to be worth alot, but is a worthy, easily maintained bike once it's fixed up. There must be options without splashing too much cash IMO. 1980 KZ400 B2, UK. Owned from new. Good luck.

[@robertjvigil6262]

I went threw the same thing you are going threw with the contract breaker I had to purchase one on eBay lucky I found a nos for 150 you can get the springs and I think that one should work just fine if you can't find one new or good used good luck

[@johnpeterson3955]

I don't know what you've decided to do with this bike, but I'm currently working on the same model year and took the time to watch your video, and a couple things came to mind. Number One, do you have a manual? (2), I think your concerns about the oil drain are a bit alarmist - true, a bit of metal in the oil is a no-no, but from what I could see it was only around the threads of the bolt; it looks rather like it was cross-threaded...I would get a thread chaser, put some grease on it and just clean up the threads and/or flush the case. If you're worried about any metal being *inside, well, there's only one way you'll know for sure, and that's to open it up! I understand your reluctance to do that, but it's not that hard and you'll learn a lot. Don't be afraid of it, motorcycle engines can smell fear...;) Yes, finding a spark advance for this bike (and pistons! The part number for pistons for THAT bike is 13001-1001 and harder to find than an honest politician - AMHIK!) is difficult, but IMO the part you were concerned about with all the pitting doesn't look all that bad to me, I've seen worse. It rides on the points shaft through the spark advance and has a "bulge" (for lack of a better term - I can't remember what they call it exactly) that - as the shaft turns, it opens and closes the points themselves to send the spark down to the plugs. Give it a good polish with some sandpaper and let it go. Speaking of the pistons, I agree with Scott Minshall - it looks like the pistons got good and hot, which MAY have led to a failure of the piston rings and loosened it up *just enough in the cylinder to cause that scuffing on the piston skirt - I think this because your video shows all the broken bits of ring you took out, and a small crack when the engine is cold can turn into a big crack when the engine is hot. You're lucky they didn't come out inside the engine and Really cause some problems! I think you'd be okay with cleaning them up and getting some new rings. But as far as opening up the engine, well...only you can decide.

[@aztriumphster]

Thank you for the detailed reply. I ended up buying a second motor which has a good spark advance and no issues with the drain plug. Everything seems to move smoothly and the reputable seller i bought the motor from says it has good compression. I've already picked up a handful of additional components to get closer to firing this thing up, video coming soon. I am finding that checking the valve clearances is proving a bit difficult, only because I can't seem to get the feeler gauge in there. Did you have to use 90 degree feelers to check/adjust your valves?

[@dougm4072]

@@aztriumphster i had to put a creased bend in my gauge for my 78..

[@scottminshall6420]

All right a couple of things, first your this far along it would be a shame to stop now. Your dealing with Vintage Japanese bike and the market is pretty good on them restored, resto-moded, café racer, and even as a scrambler/flat tracker bike. I think someone got it good and hot running it hard and that is what your seeing in the pistons. I would go and media blast them with a media like walnut shells, it should remove the carbon and not any metal. Do a really good hone job on the cylinders with a strong cross hatch a new set of properly fit rings and she she be as good as new. Drain plug should be as easy as a helicoil insert in fact the threads in the case are jacked just drill and put in the helicoil. I would go to Walmart and buy a couple of quarts of cheap oil and flush the case out. It looks as though when is sat someone left it where it could get water in it like by some sprinklers or something similar and that's what happened to your points and ignition items. You can always have some of those parts made/machined if that is what is needed. Next thing is reach out to Taylor at kzbin.info

[@scottminshall6420]

Taylor might have the parts you need, Also look into kzbin.info they specialize in vintage Kawasaki's. And if all else fails and you decide to call it quits they may buy the project from you. I would keep going but that's me, Good Luck keep us updated.

[@philjean9403]

I'm doing the same one get more dedicated like really that's all I know

[@NoahT98]

What did you end up doing to the bike?

[@aztriumphster]

Bought a new motor and started a custom build

[@NoahT98]

@@aztriumphster You still have the old head?

[@aztriumphster]

@@NoahT98 yes

[@NoahT98]

@@aztriumphster If your willing, i might be interested in buying the head. I'm rebuilding A 78 kz400 and i broken off a bolt at the exhaust port. If I fail to extracted I"ll be in trouble.

[@aztriumphster]

@@NoahT98 any luck with that bolt?