robs ss
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- Aug 16, 2016
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During an idle moment I decided to check if the internal bore of the drive side of the camshaft of my 650SS in case it might be partially obscured with build-up, etc.
First I tried blowing into it, from the drive end - no luck, it seemed to be totally blocked
No problem I thought so I tried digging into it with bamboo cooking sticks but found it was still blocked
"Well I'll drill that crap out" I thought and started with a 3/16" bit
I was concerned when metal swarf came out so shone a torch down it only to find... it was completely blocked with solid metal - never was hollow from the DS lobes to the "breathing" holes
No wonder "cam breathing" Nortons have such a bad reputation for leaking oil!
I wonder how many other 88s, 99s, Manxmen, 650ss, Atlas and Mercuries out there are suffering from leaks thinking their breathers are working???
I am going to fit a breather (a la Jim Comstock) at the lower rear of the crankcase but thought I'd let others know what I'd found
Photo of the cam ID below
Cheers
Rob
First I tried blowing into it, from the drive end - no luck, it seemed to be totally blocked
No problem I thought so I tried digging into it with bamboo cooking sticks but found it was still blocked
"Well I'll drill that crap out" I thought and started with a 3/16" bit
I was concerned when metal swarf came out so shone a torch down it only to find... it was completely blocked with solid metal - never was hollow from the DS lobes to the "breathing" holes
No wonder "cam breathing" Nortons have such a bad reputation for leaking oil!
I wonder how many other 88s, 99s, Manxmen, 650ss, Atlas and Mercuries out there are suffering from leaks thinking their breathers are working???
I am going to fit a breather (a la Jim Comstock) at the lower rear of the crankcase but thought I'd let others know what I'd found
Photo of the cam ID below
Cheers
Rob