What size plug recommended for this cooling head?

inspectorcritic

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I'm interested in more power better performance yesterday on another used bike I swapped plugs out with B8HSS I think it cured a lot of bugs got a lot more speed until I got to a uphill stop light look down the head was smoking and I could smell the plug wire burning, scarry harry had to get it out.
But I presume a cooling head is so you can run a hotter plug for bitter performance, what number?
Excuse me if I got repeat pics can't delete one without deleting them all, slow board response.
IMG_20190709_112205386.jpg
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Spare_Parts

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Lower number is hotter with ngk. Since your bike is pretty stock a b6hs unless it gets very hot in the summer then use a b7hs.
 

inspectorcritic

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I believe the b6s has a shorter stem it would be firing in the pit not the fire bowl losing compression with expansion.
Got be one design with longer stem for this monster head that probably runs hotter.
 

gary55

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Nov 27, 2012
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3,726
I'm interested in more power better performance yesterday on another used bike I swapped plugs out with B8HSS I think it cured a lot of bugs got a lot more speed until I got to a uphill stop light look down the head was smoking and I could smell the plug wire burning, scarry harry had to get it out.
But I presume a cooling head is so you can run a hotter plug for bitter performance, what number?
Excuse me if I got repeat pics can't delete one without deleting them all, slow board response.
View attachment 88690View attachment 88689View attachment 88689View attachment 88689
If that head is smoking hot the problem is not the B8HSS plug. If I were to guess the reason from the pic. alone I would say you were sucking air in through the exhaust. It appears to be missing the gasket. That and the excess oil it's absence is putting on the head is more likely the issue. Try replacing the gasket and a little clean up on the engine to see if that helps. If so yay. If not you'll need to find out why it's running hot 1e air leak somewhere else.
 

inspectorcritic

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Joined
Dec 13, 2015
Messages
1,037
If that head is smoking hot the problem is not the B8HSS plug. If I were to guess the reason from the pic. alone I would say you were sucking air in through the exhaust. It appears to be missing the gasket. That and the excess oil it's absence is putting on the head is more likely the issue. Try replacing the gasket and a little clean up on the engine to see if that helps. If so yay. If not you'll need to find out why it's running hot 1e air leak somewhere else.
Ok thanks for advice possibility but it was not smoking before installing the plug then after I change the plug the over heating issue subsided.
Perhaps the plug was firing at the wrong piston position and suck the air in at wrong time.
 
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