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Discussion Starter · #6 ·
Fair amount of carbon built up on the top piston, but I don't know if that's normal or not.

I can say the bike ran pretty well, but was consuming oil. About 1 quart every 200 miles as I recall.

Oddest thing was during cold starts it would sometimes not fire on both cylinders for the first 30 seconds.
 

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Oh okay. Your post#1 indicated that you thought you had low compression on one cylinder. What made you think it had low compression and what were the actual, measured compression values?
 

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You haven't removed the valves and on the first picture, the bottom left valve looks like something is going on there. You have to remove the valves, make sure you mark which valve goes to which hole, and you may have to hand lap them back in. Some Dykem sprayed on there, of even a Sharpie pen, will show you where leakage is occurring when you spin the valve (by hand!), the ink well not all scrap off if there is a leak. In any event, with the head off, remove the valves, get some lapping compound, a suction cut on a stick and by hand, lap down the valves till you have a nice shiny seat that matches on the valve. Get al that carbon off everything. Polish the valves with rouge and the same with the top pf the pistons. You don't want to take off metal, you want them shiny. The cylinders have to come out, losing that much oil, if the bore is straight, you might get away with slapping in a new set of stock rings, if it is worn, then you will have to bore, get new pistons, to the next bore size. When I take an engine apart, I expect the worst, and I don't skimp on anything if I decide to put it back together. ;)
 

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Compression testing must be done with the throttle wide open and preferable on a hot engine.

As it stands now the difference in pressure between the two cylinders is concerning. The lower compression of the front cylinder lines up with the excessive carbon found on the piston of the front cylinder. So you may need new rings or new valve guide seals, but as Kawasakian points out, you might as well do a top end job while you are in there.

You can easily check the sealing of valves by pouring some kerosene into the cylinder head ports to see if any will leak past the valves.
 

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Discussion Starter · #14 ·
Anyway I will do some tests and see what I find, and report back. Thanks for all the info and tips, this is the third post on a Kawasaki forum looking for guidance and it has been ghost towns til now.

Much appreciated 👍
 

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They are definitely harder on the starters and batteries without, but will run OK,,,
 

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Discussion Starter · #20 ·
Got back to investigating this morning. For the valve leak test I flipped them valves down and filled up above the valves with pb blaster because I don't really have a good way to get kerosene out of the can and into the ports. Some of the valves look to have a little seepage around them, but nothing substantial.

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