Nashville Kat
Well-Known Member
Just putting another jug on my 50 because it has strange "sleeve" intake and wider studs and a carb with a jet that's not otherwise like normal NT-
ANYWAY- I've been getting some leak from the new head- felt the hot breeze and seemed louder- not performing-
I've got three gaskets here- all are supposed to be 50 gaskets I believe- yet on only one of them the material comes all the way to the edge of the head and cylinder indentation, while the other two have less material that ends a good 1/8" away from the cylinder round- only halfway across the raised metal surface on the head.
I put the widest one on (laterally, not thickness-wise), and went back to the older head that was not leaking otherwise. On a short test ride this evening, it seemed to be working fine- ready for some break in.
but a little troubled by the difference in the gaskets- not sure if I could have been sent 66 instead by mistake or negligence- and I don't want to take my 66 apart just to see! I think the wider material one is actually NOT the original, but the second of three from BGF-and counting the original one which was never any problem- Ithen didn't notice a difference when I replaced it.
But as far as it all goes- the WIDER one is obviously a better design- particularly given the raised "O" surface on the head contact point- the other two only cover half of it- a NEGATIVE situation- I'd be better off with NO raised metal section on the head to get more mating surface, from the rest of (and the most of!) the gasket. It just hangs there, not compressed as tightly.
I've been just filing the seeming troubled new head- it was leaking twice with different gaskets-
anyway I was wondering if there is a THICKER metal gasket for sale out there- the gaskets are so thin- obviously one another half or more in thickness would last longer and be more trouble free- A thicker gasket would better compensate if the raised circular metal ridge is just "getting in the way" of the rest of the gasket making contact. The head would just be getting tightened down onto HALF of that circular ring, and then NEGATING the rest of the gasket if I used those two flimsy gaskets.
I don't worry over any slight difference in coimpression. And then, the gasket SHOULD come all the way to the circular edge it seems to me, for maximum mating surface. The gasket should be designed to be flush on all it's surface it seems only logical to me- not just that circle or even just HALF that circle.
I just searched "two gaskets" on the engine, and there have been comments about having two gaskets- but that still leaves room for blow-by in the middle- if I HAD to use the other gaskets, I'd probably put both on. What is the material? Aluminum? Thinking of cutting one out of some sturdy pie plate.
All this was so I could replace the carb- and now I think maybe I could have done that on the old head and jug with a 40mm spaced billet intake, to take the NT Speed carb instaed of the original dog carb. The cost would have been about the same , and I'm learning stuff otherwise- and maybe I DIDN'T want to know it!
Looks like theres a market for someone who could make a better head gasket...
ANYWAY- I've been getting some leak from the new head- felt the hot breeze and seemed louder- not performing-
I've got three gaskets here- all are supposed to be 50 gaskets I believe- yet on only one of them the material comes all the way to the edge of the head and cylinder indentation, while the other two have less material that ends a good 1/8" away from the cylinder round- only halfway across the raised metal surface on the head.
I put the widest one on (laterally, not thickness-wise), and went back to the older head that was not leaking otherwise. On a short test ride this evening, it seemed to be working fine- ready for some break in.
but a little troubled by the difference in the gaskets- not sure if I could have been sent 66 instead by mistake or negligence- and I don't want to take my 66 apart just to see! I think the wider material one is actually NOT the original, but the second of three from BGF-and counting the original one which was never any problem- Ithen didn't notice a difference when I replaced it.
But as far as it all goes- the WIDER one is obviously a better design- particularly given the raised "O" surface on the head contact point- the other two only cover half of it- a NEGATIVE situation- I'd be better off with NO raised metal section on the head to get more mating surface, from the rest of (and the most of!) the gasket. It just hangs there, not compressed as tightly.
I've been just filing the seeming troubled new head- it was leaking twice with different gaskets-
anyway I was wondering if there is a THICKER metal gasket for sale out there- the gaskets are so thin- obviously one another half or more in thickness would last longer and be more trouble free- A thicker gasket would better compensate if the raised circular metal ridge is just "getting in the way" of the rest of the gasket making contact. The head would just be getting tightened down onto HALF of that circular ring, and then NEGATING the rest of the gasket if I used those two flimsy gaskets.
I don't worry over any slight difference in coimpression. And then, the gasket SHOULD come all the way to the circular edge it seems to me, for maximum mating surface. The gasket should be designed to be flush on all it's surface it seems only logical to me- not just that circle or even just HALF that circle.
I just searched "two gaskets" on the engine, and there have been comments about having two gaskets- but that still leaves room for blow-by in the middle- if I HAD to use the other gaskets, I'd probably put both on. What is the material? Aluminum? Thinking of cutting one out of some sturdy pie plate.
All this was so I could replace the carb- and now I think maybe I could have done that on the old head and jug with a 40mm spaced billet intake, to take the NT Speed carb instaed of the original dog carb. The cost would have been about the same , and I'm learning stuff otherwise- and maybe I DIDN'T want to know it!
Looks like theres a market for someone who could make a better head gasket...
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