Odd Oil Leak

Just wondering if anyone else has experienced what I have. Obviously for a host of reasons from Corona to weather, I have not put many miles on my recently rebuilt KZ-1000A1. Yesterday because it got relatively nice out, 52 degrees, I decided to chance a ride of a few miles. When I pushed the bike off the lift and started it I had my old nemesis oil leak return from the head gasket by #3 exhaust. Not much of a leak, but a leak none-the-less. Probably pooled about 1 inch or so on the ground. This happened several weeks ago and I thought I cured it with a re-torque on the head, but guess not now. I wiped up the oil on the floor as the bike was running and surprisingly enough there was no more oil. The oil was visible on the seam between the head and cylinder but no more on the floor. So casting fate to the wind, I went out for my ride of about 50 miles and returned home. Got off the bike while it was running and noticed no more oil.

So I thought about this problem and clearly, in my mind anyway, the head gasket leaks when cold but stops leaking when warm perhaps due to expansion of the components. So this morning I pulled the fuel tank and re-torqued the head cold, but added 3 extra foot pounds. So instead of 31 foot pounds max. as called for in my KSM I am now at 34 foot pounds. While it is true I have exceeded the recommended torque by 3 foot pounds does anyone see anything wrong with this experiment as such? I started the bike up after doing this and there is no oil leakage at this time. That's not to say it won't return, but it's leak free now. If in fact it should leak again I will take it apart to try and determine what the problem is. I have a one-piece head gasket in the engine now, but I do have a new OEM two piece gasket and o-ring that I could try. If it comes to this I also will install APE heavy duty cylinder studs which sadly, is what I should have done when the engine was apart the first time.

Thanks for any thoughts on this matter, I appreciate your time.
Rick H.

hi rick can i ask you about the 1 piece head gasket ,what make it is and is it 70 or 72 mm the later seems to be more common ,thanks david

Are you certain the source of the leak is your head gasket? The area you referenced is also where the tach cable enters the head. Did you replace the gasket and O-ring on the tach gear?

When it comes to head gaskets I only use OEM (hence two piece) gaskets, but I spray them with Permatex copper. I've never had a leak. From memory, OEM head gaskets are expensive at around $60 each. But they are the best around as far as I've found.

Torquing your studs by an extra 10% means you're putting more tension on them. If they didn't snap from the extra torque I would imagine they are OK.

david richard wrote: hi rick can i ask you about the 1 piece head gasket ,what make it is and is it 70 or 72 mm the later seems to be more common ,thanks david

David: I bought the gasket from Redline Cycle. Jim claims they are the best thing going right now. I went with a 1045 kit in my KZ and I believe the gasket he sold me was a 72mm one. I made every attempt at proper installation as there is a recommended procedure for this. I was pretty surprised that it leaked, because short of having someone come over and do the install for me I followed instructions to the letter. I may have messed up the filling of the grove for the o-ring with sealer, but I thought I had it right. If it comes apart again the APE studs will be installed for sure. Should have listened to the wise men here.
Rick H.

hardrockminer wrote: Are you certain the source of the leak is your head gasket? The area you referenced is also where the tach cable enters the head. Did you replace the gasket and O-ring on the tach gear?

When it comes to head gaskets I only use OEM (hence two piece) gaskets, but I spray them with Permatex copper. I've never had a leak. From memory, OEM head gaskets are expensive at around $60 each. But they are the best around as far as I've found.

Torquing your studs by an extra 10% means you're putting more tension on them. If they didn't snap from the extra torque I would imagine they are OK.

Hardrockminer: Yes sir I checked the tach drive when I first noticed the problem. That is definitely not the source of the leak. I really wish it was, but not my luck. The darn bike runs really well from what I can tell so far and I hate to take it apart again. If I have to so be it, but APE studs will go in if I do. That's interesting you use copper spray on your gaskets. I thought that was the kiss of death on those. In retrospect if I have to take it apart again now would be a good time with the "stay home" orders in effect. Maybe I will try the OEM gaskets as I have four sets of them. Do you do anything special with the O-ring seal?
Thanks....
Rick H.

i know you have more experience than me with these motors the reason why i ask i have a z1r and it needs all the cam wheels etc replacing and i am not sure which gaskets to use i feel for you after all that work and exspence it appears that people are split which to use ,david

Everybody has their own opinion on how to put their motor together. Well here is mine!!!!

When I back off the head nuts, I loosen them in a reverse pattern of the assembly sequence. And I loosen them maybe a half turn at a time. I NEVER loosen one head nut all the way then proceed to the next head nut.

Make sure both the head and barrel are flat. Invest in a good straight edge to check them. A piece of steel is not going to cut it.

In all of my motors I have always used O.E.M. Kawasaki gaskets. My 1015cc motors I used the stock Kz1000 head gaskets (11004-076) My 73mm motors I used the '83/'84 ZX1100 (GPz1100) head gaskets. The 1000 head gaskets I always coated with K&W Coppercoat. The brush on type ONLY. I always used the O.E.M. center O-ring. But I always coated it with Three Bond TB-1211. I never used more than the stock head bolt torque listed in shop manual!!!!! And I also follow the torque pattern listed in shop manual. I never fired the motor up until it sat for at least 24 hours after it was assembled.

Going back through my Superbike logbook, I assembled my 1015 motors 24 different times over the years that I raced it. NOT ONE OF THOSE MOTORS EVER DEVELOPED ANY TYPE OF HEAD OR BASE GASKET OIL LEAK. I did have a small oil leak from a cam plug one time back in '81. Another thing to remember is that a road race motor spends its whole life between 5,000 to 10,500 RPM'S!!! A normal race weekend would put about 125 to 175 miles on a motor. 125 miles is equal to 500 trips down a drag strip!!!!

Well thats my two cents!!!!!!

A good quality straight edge checking for warpage


The TB-1211 sealant in and around my center O-ring before assembly.


The ONLY thing I have ever used on my motor gaskets!!!

Makes good sense! Myself, I am a fan of HYLOMAR sealant. I heard that from Elmer Trett in the late 1980's. Said it was the only thing that sealed his head on the Nitro Fuel bike. And just last year we used it on a AA/Gasser Alcohol car burning methanol with a blower. Previous to this, Friend Al used the copper spray from Permatex. After 1/2 season you could see copper blow by on the firewall. 1954 Chrysler Hemi's were not built to race with 1400 hp. in the day. But after using the hylomar, no more blow by. And that is with 1 piece copper gasket. Both head and block are O-ringed with Stainless wire. He paid $200 for some stainless 4 ply laminated gasket, they sucked! just pulled this out last week for new connecting rods! Billet rods last about 100 runs safely. Sorry for the tangent. But research "hylomar." good stuff

Nothing special with the center 0-ring. Just be sure it's in place before sliding the head onto the studs. I don't use a lot of Permatex...just enough to make the gasket a bit tacky (both sides) so that it seals on the metal face. It's also really important to have both metal faces ultra clean....Here is my most recent one from this winter.

MLS (multi-layer steel) are the highest quality head gaskets used by the automotive industry for decades. They require smooth flat decks and are now available for KZ and J engines.. One piece, no o-rings required.

www.wiseco.com/ProductDetail.aspx?ItemID...ear=1977&AppID=66303