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Discussion Starter · #1 ·
I'm trying to decide if I can hone the cylinders and reuse rings on ZX11 pistons. The cylinders look clean and low miles. Will I regret this?
 

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You might. If the cylinders need honing, then likely a good idea to just replace them since you are in that deep. I would either leave it as is (if everything is fine) or replace rings and hone cylinder. JMO.
 

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I wouldn't reuse piston rings. Rings are one of those things you should always replace any time the pistons are out. First get yourself a service manual. Before re-honing the cylinders, measure them with a set of dial bore gauges, or telescoping gauges, and use dial caliper or outside micrometers to make sure the cylinders are not out of specs. Also measure ring gap. Good luck.
 

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Rings wear in to their original bores. They also wear in a slight arc, not perfectly flat. Although their end gaps may be within spec, they will not seal onto a new bore surface as well as new rings will. Replace 'em while you're in there. It's cheaper than having to go back and do it again, or suffering premature loss of seal, leading to early overhaul.
 

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Discussion Starter · #5 ·
Ok thanks, sometimes I can be too cheep.
BTW while reading up on the ZX11 I learned the engine was canted forward more from the ZX10 to make room for the ram air system. Since the bottom end design remained from the earlier models (abet with a larger crank journal) I have to wonder if this contributed to the oil starvation issue.
 

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The only things canted (also on the ZZR 1200) are the intake ports. The 11 and the ZZR have downdraft heads where the rest of the range and ancestors going back to the 900 Ninja have sidedraft heads.

Oil starvation relates to oil level, which during a wheelie can be less than the level of the oil pickup. There were also issues with alignment of crank journal drain holes with those of the bearings. This would hold up the flow leaving too much in the top end and not enough down low at higher rpm. The latter is rare and manifests itself fairly early on in an engine's life. Most owners keep the oil level at the top of the sight glass for insurance.
 

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Oil pumps on many Kawasaki engines models are a trade-off. They are street engines turned race engines for a few of the models. You need good oil pressure at idle, but that overwhelms oil drainage from the head at sustained high RPMs causing oil starvation. Many of the engine designs offered a Kit oil pump with lower initial pressure and high volume for race bikes, but that meant one of the pit team had to keep RPMs off idle before the race so there was enough oil pressure to not starve the engine.
 

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I thought Kawi purposely moved the motor forward on the ZX 11 and 12 and the 14 to help keep the front tire from lifting on a launch. I guess it would make sense to give them some more room at the top back corner of the frame to make some more room for the Ram Air.
On another note, I cant think of a better time to install rings on the 11 your working on, Can you? : )
I agree with Hammerhead that a fresh hone and new rings ware into a matched set. I think if you honed it and used old rings the outcome would be less than desired.
 

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Discussion Starter · #10 ·
I went ahead and ordered a '89 ZX10 block to do an overbore to ZX11 specs and start with everything inside fresh. Boring 2 mm off the ZG1000 and installing ZX11 pistons worked nicely so I guess this should too. Hopefully. I had to swap con rods to ZX10 on that to get the deck height.
 
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