1981 Kawasaki GPz550: Restoration

[srsupertrap]

I am speculating a lot and not having a lot of experience with motorcycle engines which make loud knock noises take anything I say with a grain of salt. I pulled the valve cover and measured the GPz550 valve clearance. Expecting real bad considering the engine knock but measurements look correct. Recall I had a machinist remove material from the valve stem tips, the 11/12 date shows valve clearance after it was reassembled. The 4/5 date shows the measurements after starting this weekend and said knocking noise.

After checking valve lash, I noticed the intake cam oil galleries did not have any oil in them. The exhaust cam galleries did. I removed the spark plugs, turned the engine over roughly 20X by hand, saw the oil level in the sight glass drop but no additional oil up in intake cam oil galleries. I would suspect the oil pump is working if the oil level drops while turning the engine over but not having oil circulating could certainly explain a knock noise right . . .

GPz550 Valve Clearance
Date: 11/12/16	Cyl 1	Cyl 2	Cyl 3	Cyl 4
In .004-.008	0.009	0.007	0.008	0.008
Ex .006-.01	0.01	0.011	0.01	0.011
Date: 4/5/17	Cyl 1	Cyl 2	Cyl 3	Cyl 4
In .004-.008	0.008	0.005	0.007	0.009
Ex .006-.01	0.008	0.008	0.007	0.01

[Nessism]

Sounds like a stupid idea but can I learn anything from running it with the valve cover removed?

You can learn how fast the engine can dump 4 quarts of oil on the ground. Not a good idea.

When you replaced the valve spring retainers did the shim stick up above them? Was the shim sitting on the top of the valve and not contacting the keepers?

[srsupertrap]

You can learn how fast the engine can dump 4 quarts of oil on the ground. Not a good idea.

When you replaced the valve spring retainers did the shim stick up above them? Was the shim sitting on the top of the valve and not contacting the keepers?

IIRC, I checked the valve stem keepers were below the top of the valve stem tips, i.e. the valve shim was not contacting the keepers. I will of course verify when removing cams tonight . . .

4/7/17: Removed the intake cam to get a look under the buckets. If the keepers were contacting the valve shim damage would be evident. What caught my eye and hopefully yours in the first photo . . . there ain't much oil up there considering the engine ran and the oil gallery under the cam bearing cap is quite large.



Removing the buckets on the intake cam where I believed the knocking noise was coming. The valve stems are not damaged and valve keepers are in place. NOTE: Look at 2 & 3 valve retainers you will see where the machinist milled off the top of the valve spring retainers. Ok, that makes me feel better but doesn't solve anything. Back to August 2016, what other damage could have occurred when #1 piston chewed the spark plug electrode?

Could the connecting rod bend? Second why isn't there any oil up in the cylinder head galleries . . . the GS has a big pool? From the previous page, I also heard some mechanical noise when shutting the engine off ( Chink, chink . . .). Clearly not a valve keeper.

Looks like this is more than just removing the Head & Cylinder

[srsupertrap]

1. Removed the main oil galleries drain plug which is below the points cover
2. Turned the crank over with a ratchet by hand several times and some oil came out.
3. Then the crank jammed, figured the cam chain got jammed so removed the exhaust cam. Still jammed
4. Using two 1/4" drive as a gages



Number #1 piston is not happy

[srsupertrap]

Oh boy #1 exploded


Connecting rod must have bent back in Aug 2016. Both nuts came off the connecting rod bolts






Crank journal looks good but without measuring it's probably a boat anchor

[Nessism]

Damn Steve! That's some seriously bad luck there.

Keep your head up buddy! It's only money!

[rphillips]

Gosh, hard to imagine such a bummer. But on the positive side, the second time around is always much easier than the first, the accumulated knowledge works wonders. May want to sit back & take a minute. Those are great little bikes, & when completed you'll have both a great bike & a whale of a story. Surely you've used up all the bad luck. Keep us updated.

[roeme]

Such bad luck, but I'm learning a ton just by reading. Friend of mine own's a Z500, loads of fun.

[SVSooke]

When you said bigger problems I never imagined this

[Corey]

Oh, so this is where you've been hanging out all these years! I applaud you for sticking with it.

Corey

[Cipher]

Im surprised that did not bust your crankcases or do some other sort of horrible damage.
Did you dind all the bits in the oilpan?

Are these parts still available?

[Ghostgs1]

Steve, Sorry to hear this, that's worse than I was expecting. I think you are correct, all related to the spark plug insulator. Doubt much more damage was caused by the recent attempts at running it, probably all from first start. New liner, rod, bearing insert, but hopefully the crack can be salvaged. Ray

[srsupertrap]

Oh, so this is where you've been hanging out all these years! I applaud you for sticking with it.

Corey

Hey Corey,
Thanks for watching and checking in, never thought the GPz550 project would take this turn or take so long. For the GS Resource forum community, introductions are in order, Corey is The GPz 550 Forum administrator, resident Subject Matter Expert on all matters of GPz550s with over 16K replies, owns a GPz550 track bike, daily rider as well, overall great guy and works at Motion Pro too. The "Forum Newbie" tag does not apply .

I ran a 1981 Kawasaki GPz550: restoration thread over on The GPz550 forum. Although the number of GPz 550 members are smaller, everyone was just as helpful as the GS Resource Forum. When I had rotary cuff surgery in 2015, then recovered I couldn't find the old thread which explains my absence. Should have because you cannot have enough friends.

BTW, I did rebuild those Mikuni TM27 D1 Flatslides you sold me. The original set on mine sounded really good for about 1 minute.

[roeme]

Forum cross-pollination! I like it!

Definitively watching this thread.

[srsupertrap]

Thanks GSers (Nessism, rphillips, SVSooke, Cipher, Ghostgs1) for all the supportive replies. Did want to respond to Cipher's point I was able to fish out the majority of the broken parts from the crankcase. I should have replaced the connecting rod or had it inspected back in August . . . Oh well. I don't the trust the crankshaft now either, everything needs to get replaced. To that end, meet the donor 83 KZ550 Standard with 6300 miles

Same Crank 13031-1014, Same, Rod Assy 13251-1004-KK, Same Valves 12004-1016 (In) & 12005-1013 (Ex), different pistons & cams