The ZX11 oil starvation conundrum

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OK oil gurus I place myself at your mercy. I have a pending deal on a theft recovery Kawasaki ZZR1200 which is complete but the owner bought it to swap the engine into his ZX11D model so it will come with the knocking connecting rod. I have rebuilt bike engines before and did some assembly work on hobby drag engines including supercharged gasoline and methanol fueled so I am temped to take the project on. These engines had issues with oil starvation and many cures were developed from internal and external oil passage rerouting, restrictions to boost crankshaft pressure, and the cure that I am inclined to follow, deburring and port matching. Do any modern oils offer a level of protection above those of the era? I used to run Valvoline automotive racing oil years back. A thread I read carefully. TBH I got a headache trying to absorb it all. https://www.zxforums.com/threads/oil-starvation-3-rod.5394/
 
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I'm a bit confused ... so is this ZZR1200 has an older ZX11 engine put in it? Now do you know this ZX11 currently has a "knocking rod"? I read through some of that thread, and what makes sense to me more than most of the talk in that thread is guys finding misaligned oil feed holes in the bearing cap (post #32 in that thread). That might also explain why not all ZX11s show this problem. Different oils might give different levels of protection once metal-to-metal contact occurs, but journal bearing protection is mainly based on what viscosity is uses since journal bearings rely solely on hydrodynamic lubrication. If there is an oil volume flow issue (as discussed in post #32) going on because of improper machining/manufacturing, then the issue isn't going to be saved by using different brand oil.
 

IMSA_Racing_Fan

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Originally Posted by ZeeOSix
I'm a bit confused ... so is this ZZR1200 has an older ZX11 engine put in it? Now do you know this ZX11 currently has a "knocking rod"?
It is disassembled but complete sans a tire (I don't ride on old tires so not a problem) and comes with the ZX11 engine the guy swapped out.
 
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Originally Posted by IMSA_Racing_Fan
Originally Posted by ZeeOSix
I'm a bit confused ... so is this ZZR1200 has an older ZX11 engine put in it? Now do you know this ZX11 currently has a "knocking rod"?
It is disassembled but complete sans a tire (I don't ride on old tires so not a problem) and comes with the ZX11 engine the guy swapped out.
What year ZX11 engine ... and how many miles on it?
 

IMSA_Racing_Fan

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1994 ZX11D, I don't have the mileage right now will ask (guess I should have already). One side question:. I have always wondered about oil coolers on bikes and start-up. Since they're almost always mounted up high on the frame shouldn't there be an aeration/starvation in the first moment after starting?
 
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Originally Posted by IMSA_Racing_Fan
1994 ZX11D, I don't have the mileage right now will ask (guess I should have already). One side question:. I have always wondered about oil coolers on bikes and start-up. Since they're almost always mounted up high on the frame shouldn't there be an aeration/starvation in the first moment after starting?
Oil coolers are parallel flow, not series flow. So the main oiling system flow shouldn't be effected by an oil cooler.
 
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1991 kawasaki zx11 owner here back in the day anyway. I can even tell you which cylinder this will be. #3 I had this happen twice to my 1991 zx11. during the second instance we were in the process of going back together and while reading through a magazine I seen a add by falcon or falicon I'm pretty sure it was falcon. Anyway it read ZX11 owners trouble with #3 rod/crank issue we have the solution. I had to send them my oil pan and they did some type of mod that sent extra oil to that problem area. Never had a single issue again. And this bike was rode hard. We used to just do stand up wheelies on the highway and this is when it happened the first time. Not sure if falcon still exists but try researching this. It worked for me I sold the bike years later still running like a top.
 
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It's Falicon. They're still around. Falicon Cranks But it appears that their business model is possibly changing. I have a Falicon forged stroker crank in my 'Busa. 285 rwhp, 160 rwlb-ft. No issues in 10 years in that configuration. My '97 ZX-11D never had an issue with crank oiling. Cam pitting however was an issue.
 

IMSA_Racing_Fan

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I performed a wheelie on a GPz750 with a fat kid on back for a crowd waiting for Iron Maiden tickets. He didn't hold onto my waist but my t-shirt, slid down stretching my shirt which put us vertical with his [censored] on the taillight. Came down hard sideways. The crowd cheered like mad and he jumped up with road rash on his chubby arm pumping his fist shouting "ROCK AND ROLL"!!!
 
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Went to lots of concerts in the 80's, including Iron Maiden. Never came away with road rash, however. grin Being a Motorcyclist back then, I did always have foam earplugs. They cut the decibel level enough that I still have pretty decent hearing today.
 

IMSA_Racing_Fan

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On the same bike earlier that year a party I crashed ran out of beer so they gathered money for another keg. This one older, skinny drunk in cowboy boots asked me for a ride to the beer joint so I obliged. As the caravan merged from one downtown highway to another I blew by pulling a power wheelie then felt a thunk under both armpits. It was cowboy boots! I slammed it down and his head thunked my helmet. Hard. When we got to the bar the people in the were laughing, "man he was spread eagle with his head almost on the pavement" and that guy was like "sheeeit pardner I'm gonna ride in the truck goin' back".
 
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I know the ZRX 1200 pretty well and have a ZZR 1200 engine on a pallet in my garage that donated the cams and double valve springs into my ZRX 1200. I run a ZX11D ECU (in conjunction with the double valve springs allows an 11,500 RPM rev limit and provides the more aggressive timing advance curve of the ZX11) and timing rotor along with JE 12.5:1 pistons and have adapted ZX11/ZZR1200 40 mm carbs on to the side draft head. With a full muzzy exhaust system and stick coils from a ZX-14, the bike fairly much gets on down the road... The rod knock could be from the engine being on its side if the bike was laid down. And it's typically the #4 bearing from oil starvation. Cam pitting typically is visible however is usually not an issue and thousands of ZX11's, ZZR1200's, ZRX1200's have been run over the years with pits that would make your eyes grow big in your head. I had Webcam copy the ZZR1200 cam profile and they have those on file. The ZRX 1200 has to run the ZZR 1200 cams as they are a slightly different length than the ZX11 cams. ZX11 cams are plug and play into the ZRX1100. The ZZR1200 is the same profile as a ZX11 so if you send them cores they will make you a set of hard weld replacement cams. With that said, ZX11 cams are not that hard to come by so I would probably just keep buying cams if they pit and it bothers you. Otherwise just run then with pits and you'll never know the difference. In terms of oil, your issue with a bearing isn't going to be as well addressed with additional zinc and phosphorus as it would be if you were talking protecting the valve train. The oil isn't going to fix the oil starvation problem. Pick any good motorcycle oil that has a good zinc content for that valve train because of the pitting issue and ride on.
 
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To test for a bad rod bearing set the engine at high idle and remove one spark plug wire at a time... if the noise stops then that's the cylinder with the bad rod... if noise continues after each spark plug wires were removed then the noise is something other than a rod knock because a rod will not produce a knock by just turning over the piston... it takes the spark of combustion to produce a sharp metallic sound... Possible scuffed piston is one where it started to seize and the melted metal has partial covered a piston ring... when a piston ring can not expand it makes a sharp metallic sound as the piston knocks about the cylinder wall...
 
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IMSA_Racing_Fan

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Wow you know your stuff. At this point I'm leaning towards not going through with the deal. In the worst case it has not merely worn but a spun bearing and damaged crank and I would be sinking more money into the bike than intended. Then again cheap liter sportbikes are rare nowadays.
 
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What are you paying for this ZZR1200 and ZX-11 motor? You ought to be able to get a good deal. The motor has a rod knock it's useless other than some ZRX 1100 or 1200 owner will want the double valve springs, and a ZRX 1100 owner would probably want the cams. Also the 6-speed transmission can be swapped over to a ZRX 1100 or 1200, there is a market for that as well. You can pick up ZZR 1200 engine from eBay and plug-and-play. https://www.ebay.com/i/202897641022...J9ninfcKDvDt1jvwOMEJRBvkQiBoCP6YQAvD_BwE Of course the total cost between the two needs to be what you're comfortable with. You could also find a used and running ZZR 1200 or ZX-11.
 

IMSA_Racing_Fan

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I was thinking if the con rod bearing isn't spun can polish the journal with emery cloth, slip strips of beer can under new bearings, mic it, and run if good enough. This is old school tech. Might even reuse the head gasket after spraying with multiple coats of copper gasket spray.
 
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You must be getting a really good deal on it then. Definitely give it a whirl. I bet you could even find a used set of rods on the internet for next to nothing if you need to swap one out. You can check if the rods from a ZRX1100 would work. Those could be a cheap source as well. Hopefully you don't need any of that but just thoughts in case you do. I reused the head gasket on the ZRX the first time around when I put ZZR 1200 pistons in and removed the base gasket to gain a point of compression overstock ZRX pistons. Combined with the ZZR 1200 cams it woke that engine the heck up. Swapped over to JE 12.5:1 pistons when it broke an oil ring after 5,000 miles with the ZZR Pistons. Tried reusing the head gasket a second time with the copper spray and it did not work as well, had oil weeping out. Could have been a function of the higher compression and I ended up pulling the head a week later and putting the new head gasket on. Been trouble free well over 10,000 miles now.
 

IMSA_Racing_Fan

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Thanks again for the tips. If nothing else tearing the engine down will be a educational autopsy. In this economic downturn and my current occupation I don't bank like I did some years back.
 
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I am late to this party, but re-using a head gasket and polishing cam pitting with Emory cloth? I think both are VERY bad ideas. Japanese bikes are precision machines, not your grand daddy's 65 inline 6, 4 door Chevy II. I would pass on that deal. You can find very nice Z1200s out there for a very fair, to low, price and it would be a lot less headache and cheaper in the long run.
 
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