Maintenance & Technical > KX500 Original
BASE GASKET BLOW OUT
BDI:
--- Quote from: monster malibu on September 25, 2007, 03:32:37 AM ---I still don't know if the Cometic gasket#c7045 will work on my bike or not. My bike is a 87 kx500 with the stock bore (86mm) and the gasket Cometic lists for it is a 88mm bore gasket. Will this gasket work?
--- End quote ---
Call cometic and talk to them I think they offer that gasket In stock and over bore. I have ran over bore gasket on a stock bore In a pinch with no problem but cometic should be able to get you the right one. If you choose to run the base gasket that I like you should call and specify It because They still make the old paper ones. they are aluminum with foam rubber coating If you dont word It right they will send you steel with rubber the same thing they make head gaskets out of and the same price as head gaskets.
P.S. please make sure the bottom of your cylinder Is flat no matter how good a gasket is it will not fix a warped deck or base and It will leak again, blown gaskets usually have a root cause.
don46:
Just for kicks I went and measured a stock kawasaki and Cometic headgaskets, yep you guessed it, they measure 88 mm. The base gasket will be different between 86, 87, 88 and the 89-04 the newer motors have the 3 KIPS shafts whereas the older motors only have the 2, the cases are a bit different on the older motors as well in the KIPS area. The headgaskets are much larger and thicker on the older motors.
And as far as using Silicone for gaskets in the motor, I would'nt reccommend it, gasoline will dissolve most silicone, if you must use some sealer use something on the order of a copper coat or whatever the permatex hi-tack. I haven't bought a stock KX base gasket in quite some time, I would think they would be using the same material as Cometic since they do on the 125 and 250 base gaskets.
Mhardee:
--- Quote from: don46 on September 25, 2007, 10:08:29 AM ---And as far as using Silicone for gaskets in the motor, I would'nt reccommend it, gasoline will dissolve most silicone, if you must use some sealer use something on the order of a copper coat or whatever the permatex hi-tack. I haven't bought a stock KX base gasket in quite some time, I would think they would be using the same material as Cometic since they do on the 125 and 250 base gaskets.
--- End quote ---
Just to add more fuel to the fire :-)
Silicone Rubber is used as a gasket aid in most if not all of the race motors built today - I've built and have helped build literally hundreds of 700 - 900 HP small/big block gasoline, alcohol, nitro fueled motors. Gasoline will attack Silicone Rubber - that's a fact.. If it gets to the Silicone placed on a paper head gasket, you "fo' d**n sure" have other issues, not limited to, but most likely, a crummy mating service (i.e. gouges or warpage).
Just hate to hear blanket statements like that - most gasket manufacturers recommend it. We could all get all of this behind us if one could lay his hands on a .040 solid copper gasket and keeping his butane torch handy..
I would also like to thank you for posting the reply about the heating of expansion chambers to remove dents and the added "benefits" of heating air... I was really thinking about it... but, Alan came through with a new pipe I just got yesterday...
Mark
don46:
Cometic will make a copper gasket, definately for the head and probably for the base, they built me a couple of aluminum spacers to lift the cylinder and some .010 gaskets.
don't get me wrong, my statement about using silicone was that there are better sealers, at least in my opinion, Yamabond is one of the best but a real pain in the a$$ to clean up. I would agree with your statement about the crummy mating surface, which is what led to the discussion about the base gaskets BDI was talking about.
stewart:
i think cometic has great kx 500 gaskets i like the metal with the fiber type coating base gasket they make
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version