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I have not seen it mentioned anywhere else, but in the set-up notes (the sheet that cautions to clean the pipes) it is mentioned that the sparkplugs are oil-cooled. Nice touch. Maybe has something to do with emissions. Anybody know?
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Yes there are oil galleries that run around each spark plug seat to cool that area of the cylinder head. Honda claims this is the hottest spot on the head and the oil galleries enable this area of the CB to run on par with a liquid cooled bike cylinder head
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So long as those passages don't get coked up over time.
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(05-05-2013, 03:10 AM)Randy B_imp Wrote: So long as those passages don't get coked up over time.
Unlikely, if you stick to recommended oil change intervals. Modern synthetic oils have very high temp ratings.
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(05-27-2013, 12:40 PM)M3-SRT8_imp Wrote: (05-05-2013, 03:10 AM)Randy B_imp Wrote: So long as those passages don't get coked up over time.
Unlikely, if you stick to recommended oil change intervals. Modern synthetic oils have very high temp ratings.
Unlikely, if you stick to recommended oil change intervals. Modern synthetic oils have very high temp ratings.
I wonder if these are those bolted/screwed on finned things that surround the spark plugs on the head. Seems likely !
Then I wonder if oil is actually circulating through those finned bolt-ons or if they are fins only with no oil passages...
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I see no other purpose for them.
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Seeing as how they bolt on I doubt theres oil in there. I think they just direct additional air around spark plug base.
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4COVER, PLUG HOLE12511-MGC-920
$19.75
This is what they are called. They have a gasket that goes between them n head. Didn't see any oil passage holes in gasket, just the 2 bolt holes.
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(06-06-2013, 12:39 PM)FUZZY_imp Wrote: 4COVER, PLUG HOLE12511-MGC-920
$19.75
This is what they are called. They have a gasket that goes between them n head. Didn't see any oil passage holes in gasket, just the 2 bolt holes.
It seems there wouldn't be a gasket if they are to transfer heat away from the head.
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Yeah, thats why the crankcase and head never get hot. The gaskets stop that...