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Twin Cam 88 compression

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Old Nov 6, 2010 | 07:02 PM
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Default Twin Cam 88 compression

I have a 01 Road King with 27,000 miles. It is stock except for the V&H exhaust. When I ride with others they claim they can smell oil. I can't smell it but I've had enough people tell me about it that I did a compression check and found that both cylinders had the same compression. Not sure if the bike needs to be tuned for the aftermarket
exhaust or maybe something else is going on.

What's the stock compression supposed to be?

Could the bike not being tuned for the exhaust cause the oil smell?
 
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Old Nov 6, 2010 | 07:11 PM
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Originally Posted by 01RoadHog

What's the stock compression supposed to be?
S'posd to be 9.0:1 but in reality I'd guess it is about 8.6:1
 
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Old Nov 6, 2010 | 07:29 PM
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Originally Posted by dawg
S'posd to be 9.0:1 but in reality I'd guess it is about 8.6:1
Sorry, I meant cranking presure.
 
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Old Nov 6, 2010 | 07:32 PM
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oops sorry about that. It's about 140-145 when new
 
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Old Nov 6, 2010 | 07:42 PM
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Originally Posted by dawg
oops sorry about that. It's about 140-145 when new
Thanks dawg. Mine had 120 for both cylinders. Is that out of the norm for a 10 year old bike?
 

Last edited by 01RoadHog; Nov 6, 2010 at 07:44 PM.
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Old Nov 6, 2010 | 07:48 PM
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120 is not out of the norm.
 
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Old Nov 6, 2010 | 08:41 PM
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Are you seeing a loss of any oil?
Sometimes if you run it full it will spit oil out of the vent tubes into the intake, especially if ran hard.
You can see evidence of that (if happening) when you remove the breather.

Running a cup or so below totally full might help, but only if you are seeing the full go down faster than normal, and then slowing/stopping after about a cup or two.
 
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Old Nov 6, 2010 | 09:01 PM
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Originally Posted by flyer91
Are you seeing a loss of any oil?
Sometimes if you run it full it will spit oil out of the vent tubes into the intake, especially if ran hard.
You can see evidence of that (if happening) when you remove the breather.

Running a cup or so below totally full might help, but only if you are seeing the full go down faster than normal, and then slowing/stopping after about a cup or two.
That's a good thought because I try to run it full. I used about 3/4 of a quart over 5,000.

I noticed that my mufflers have just started to turn a slight gold color were they connect to the head pipe. I think the bike might need to be tuned but I don't know whether that would cause the oil smell. I want to make sure it's not the pistons rings or a valve issue.
 
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Old Nov 6, 2010 | 11:02 PM
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Do you have Amsoil or Mobile Syn in the trans?
The reason I ask is a friends bike that I rode with used Amsoil in the trans , and it smells pretty bad from venting.
 
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Old Nov 7, 2010 | 06:22 AM
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Originally Posted by Bill03E
Do you have Amsoil or Mobile Syn in the trans?
The reason I ask is a friends bike that I rode with used Amsoil in the trans , and it smells pretty bad from venting.
I use Amsoil in the motor and stock HD fluid in the transmission.
 
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