KX, KXT, Advice, oppions, please. KX500 Steel Sleeves.

[PLJ.]

Has anyone had any expirences with sleeving a KXT or KX cylinder with a borable, iron sleeve?? When installing the sleeve, is the cylinder bored to the water cooling passages?? Heres the scenario, I have a 2001 KX500 motor with a borable, iron sleeve installed. This was already installed when I bought the motor. After it running like garbage for awhile and seizing, I took it down. It had a blown head gasket between the fire ring and a water port, I also noticed that the sleeve was shifted or turned a bit and did not match all the ports well. I sent the cylinder to MCR and they reset the sleeve, match ported it, lapped the cylinder to the head and did a complete top end port job and head mod. I ran the motor in 4 races this past year and it just seized again. Jetting was rich and was checked all the time with frequent plug readings. In the shop, I removed the exhaust pipe to have a look at the piston. It had small drops of antifreeze on the exhaust side of the seized piston. I immediately thought that it had ate another head gasket and washed the cylinder wall down again with coolant, but after removing the head the gasket, the seal was perfect!! No apparent issues. How would this coolant be getting into the cylinder?? I can see no apparent cracks. My first thought was that the new port job and head mod had gotten to close to the coolant passages, but I cannot see anything. My other thought is what if the bored cylinder clearance was made to big for the sleeve or oblong. Could coolant leak past the sleeve, down to the crank and then work up to seize the top end?? The coolant was in terrible condition and it was not very old, only a few months. Very yellow with the coolant passages all gumed up with what looked like exhaust goo. Could this sleeve and the cylinder be expanding at different rates and causing these issues?? Any info. would be greatly appreciated. Thanks.

[jeddy]

I bought an engine with a steel sleeve to replace my engine which lost second gear and it was horrible. It wouldn't rev very well and always overheated. I put my original cylinder on it (my engine had lost second gear, so the cylinder was fine). It ran a lot better with the original cylinder, but still has a lot of vibration due to a crappy hot rods crank. My advice for you is to find a stock cylinder and go from there. Sorry to hear about you bad luck. I don't know what the problem is with the sleeve other than that they just seem to suck in general.

[tecat-z]

Yes, they generally do suck "sleeves" Find a cylinder that still has a nicasil finish and have it replated. It's the only correct way to do it imo....I can't understand why people have cylinders sleeved when they originally were plated. So many cylinders have been ruined this way, and they are always slower........

[cr480r]

I have had 2 kawasaki cylinders w sleeves that run fine.. one was a '84 tecate, and the other is the '98 KX250 I am currently using. Plated cylinders have many advantages, but sleeves can just work fine if properly installed and matched... Your barrel probably has a cracked inner water jacket that is leaking into the transfers or intake area


When installing the sleeve, is the cylinder bored to the water cooling passages?? .

shouldn't be...

[3Razors]

From an engineering standpoint the KX500 cylinder was never designed to be "sleeved". Sure it can be done but you are throwing all the benefits of a plated cylinder out the window, and I've yet to see one run as good as the way Kawasaki set it up in first place.

[jeddy]

I think Eric Gorr can replate these (Forward Motion http://www.eric-gorr.com/). I'm sure there are plenty of places that can replate a cylinder, but I'd probably go thru him due to his experience with them. I have been thinking of sending him one of my cylinders because he seems to be the guy to go to on these. Sounds like a little port work and head work goes a long way on these bikes.

[PLJ.]

Thanks for the advice and comments from all. I spoke with Eric about this cylinder the day after it happened, he is very knowledgable and is very williing to share his thoughts free of charge. When looking at this a little closer, it appears that the sleeve actually dropped down the cylinder a bit, unsealed the fire ring of the head gasket and let coolant through that way. I didnt see it at first, but a straight edge across the top of the cylinder showed that the gasket would never seal the area. P.S. my sleeve actually rotated last season within the cylinder!! When installed, the bore must have been to large, misaligned or something. It appears that I have a new paperweight with an expensive port job in it on the bench now!! Anyone have a used 89-02 KX cylinder??