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Discussion Starter #1
The person I got my bike from had the head machined. Unfortunately, neither him nor the machinest (this was probably done about a year ago) are sure how much was taken off. The machinest assures me that it was less than 15 thousandths, perhaps as little as 5. He doesn't think that much is a big deal.

The place where I bought my gasket set, they think that 15 *is* a lot, but not enough to worry about. Also, the only way to get another gasket from them was to order the entire set, which would run me another $130. He was more concerned with the valves being bent, and thinks I should look at those and not worry about the lost material.

The guy I trust the most, because he has done a lot of work for my dad, is concerned about valve clearance, compression, and timing retardation. Because I can't figure out how much was taken off the head (or how much was supposed to be there in the first place), but am pretty sure its less than 15 thousandths, he thinks putting an extra gasket under the cylinders is a safe bet. This should add an estimated 8-15 thousandths clearance.

So what I'm looking to do now is start reassembling the engine (found a kawasaki dealer that could get me just the one gasket), and then test the compression. If thats good, I can move on to rebuilding the carbs, then getting it started. Once that works, next is replace front/rear sprockets (somewhat worn) and chain. After that, it should be good to ride.

Any ideas or suggestions regarding this would be much appreciated.

Oh yeah, little history on the bike. The guy I got it from is not the original owner, and I don't know how many had it before him. He rode it for a while, then discovered a knock. Took the engine apart, and sold it to me about a year later. The guy I've talked to says the pistons and connecting rods feel good, and the knock may have been just debris in the cylinder.
 

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Gaskets

We don't know what bike or engine this is for. But...in the old days if you were serious about gaskets and making them perfect you could use different thicknesses of copper. I don't think regular gasket material with aluminum/asbestos or whatever they make them from is such a great idea...Ideally, getting the engine put together without plugs and turning it over by hand you will be able to figure out how much clearance you have by finding tdc and then tightening the valve spring and measuring the difference...or what ever your mechanic seems to think appropriate. YOu can use plastic gage, nylon line, of different sizes...once you know how much clearance you have or don't have then you can decide on how thick your gasket has to be...doubling gaskets...I just don't believe in it...ever had exhaust manifold/header leaks that just drive you crazy on your car...try the copper gaskets!!! IF this is a vintage bike ro what ever let me know what head you need, and I'll try to point you in the right direction!
 

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Discussion Starter #3
bike model

Oops, sorry bout that. Bike is a 1996 ex500. I'm trying to avoid the high pressure problems associated with the head/cylinder interface by putting the doubled gaskets underneath the cylinders, which will have the same effect, without (hopefully) compromising the tight seal needed at the top.

I intended to have a 10 thousandths or so shim made up, but the machinest thought that would be silly (and expensive) compared to simply doubling the gasket.

Thanks for the reponse.
 

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Gaskets

Gaskets are cheaper and if it works because of the increaed compression then great. Meanwhile I'd find out what the gasket is and have one made up out of copper for IF it does blow...it's just that if you have it apart it's easier to do the copper ..the "doing the job right the first time not the second, because someone "thought" it would be okay...Sorry if I sound pointed...it's just that I've been through the gasket stuff to many times with my car and my truck not to do it right on my bike...IF I had the same situation...BUT, Keep us informed!!!
 

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People in the car world use double gaskets to lower compression ratios or, like what you're doing, getting back to factory spec. You'll want to use two flat gaskets I believe, not with raised crushable metal.
 

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Discussion Starter #6
flat gaskets

Where can I find such gaskets? Or would I be better off just getting gasket material and cutting it to match the old one? Since this is under the head, I shouldn't run into any leakage problems, right? And I should be able to get different thicknesses, so I can just mic the old one (****, forgot that I don't have the old one, or at least I don't think I do ...), figure out the compression ratio of the new material, and go from there.

Anyone have a used, compressed gasket lying around they would be willing to mic up for me?

Thanks
 

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Gasket material

I don't think that the gasket material will hold up to the increased compression...that is why I suggested the copper gasket. Mr. Gasket, all the real hot Rod guys use it for their HI-Compression motors,,,I use it for my Camaro and for my truck...after replacing the gaskets with the coper ones I haven't had but to re tighten it as required after it was heated and cooled after about a week...that was over two years ago and still no leaks...And yes yo can buy it in sheets and make your own if you want.
 

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Discussion Starter #8
raising cylinders

ZX-2R, I really appreciate your suggestions, but I don't think you understand what I'm doing. I plan on placing the extra (or double thick, or whatever) gasket *underneath* the cylinder head, so that I don't run into any high pressure problems. These gaskets should not be under the same stresses as the ones at the top of the cylinder. Indeed, they should be subject to just the extra pressure created by the oil system.

That being said, I'm going to have a look and see if I can get different thicknesses of copper gasket material. If I can, what thicknesses are suggested for the *top* of the cylinders? I don't want to put anything extra there, just replace the standard one. Underneath the cylinders is where the thicker material would go.

Thanks
 

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MISUNDERSTOOD...

Thank you for being patient...and still trying to get me on the right track...now I understand Indeed I did error in what you were saying...bottom gasket doubled...okay...top gasket use the same as the standard gasket. You can use a metal-scribe, or fine point sharpie to make the pattern. in the real old days they would use a mallet...gee we've come a long ways, for the new things that we still do...
 

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Discussion Starter #10
doubled gaskets

Just to follow up, I've decided to double the gaskets. So far, so good. When I turn the engine over, the valves don't hit :)

No chance to start it yet, I still need sparkplugs, fit the carbs, oil, check radiator system, and finish the wiring. I'll post again when I know if its going to leak or anything.

BTW, the old gasket mic'd to about 13 thousdanths, if anyone is interested.
 

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Thank you for the update...

I don't keep EVERYTHING written down but it's great to follow what someone is doing. Have you done a compresion check yet...curious as to what it is brand new...so too speak.
 

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Discussion Starter #12
compression

Well, I didn't replace the rings, so it probably won't be "perfect." I'm waiting on a battery to do the test. And its supposed to be done with the engine warm, so I have to get it running before the numbers mean anything. My dad used to always do the tests cold, and couldn't understand why he was always getting such poor readings :)
 

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COMPRESSION TEST

Not only doo you have to do it while the engine is warm, but you need to have the Throttle wide open as well for a true reading...just make sure that youhave a good ground to the spark plugs hanging out in no mans land as well...or you chance messing up the ignition..
 

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Discussion Starter #14
back up and running

Bikes all back together, and everything works :D

Unfortunatly, the title got stolen by Canadians before I had a chance to transfer/register/insure. Ordered a duplicate title, so I should be on the road in about a week. I'm so psyched.

In the meantime, everything looks good. I've just been running it around my yard, tearing up the grass a little with some tail slides. I desperatly want to take it to a parking lot, but I'm holding myself back because of the legal ramifications. My college has a real nice big one though ...

Tomorrow or Friday I will be breaking it back down some, to re-torque the head bolts and check the compression, more information then. Maybe I'll snap a couple pics too.
 

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STILL CURIOUS

Still curious about your new compression ratio or at least the new compression tests...Happy that you have it back together...and at least it's running!!!
 

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Discussion Starter #17
pics

Not sure about the proper way to post pics here, so I'll just link to them:
http://mental-graffiti.com/ninja/
That bit of missing plastic on the left was held by zip strips to the turn signal and the mount point on the gas tank, but I decided to just take it off before it falls off going down the road at 65mph :) (If anyone has a fairing for a 1996 ex500 that they are looking to get rid of, I'm in the market. Any color, I'll just paint everything black if it doesn't match))

Click 'all.php' to see them all at once. I'll do the other stuff tomorrow.
 

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Discussion Starter #18
compression

Broke it back down, re-torque'd the head bolts, warmed it up to test the compression ...

and I don't have the proper size tester. One for car, one that works for my old Honda and my dad's beemers, but not one small enough for my Kawasaki.

I'm waiting on a duplicate title, once that arrives I'll take it to a shop and have it tuned up (look it over, make sure I didn't make any potentially fatal mistakes, you know) and ask them to test the compression while I'm there. Sorry ZX-2R, I'll get the numbers for you as soon as I can :?
 

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I'm just curious...

Don't hurry anything up for me...I'm just curious about the numbers to see how close they are to the book when you get done. It must be exciting having everythng all but ready to put on the road. My CRISIS situation just keeps streamlining itself, even seemingly feeding itself, as it doesn't seem to end. I'm waiting, still, to get my bike out of the salvage yard...I have not only the bike, but a BIG basket of parts from three other bikes (so far) with parts in it to put mine back together the way that I want it. My wifes situation with a diseased kidney will leave her with out one in 6 months and on a dialysis machine for 3-6 weeks before they will consider putting the donor kidney in her...her latest find of a heart problem is now being "overlooked because the kidney HAS to be replaced reguardless...so funding for my bike just keeps finding a way to slip through the cracks. I have my '74 Camaro for sale and it is truely a classic, and I have NEVER wanted to let it go, but I can't drive it with my back...setting srtaight up, where the Ninja will allow me to ride bent over...At this rate I may have my bike in time for winter...but at least I'll finally have one...
 
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