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help me understand - m8 liquid cooled or no?

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Old Dec 1, 2020 | 11:37 AM
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Default help me understand - m8 liquid cooled or no?
I have a '17 street glide with an m8, if the engine temp gets two high, there are two radiators in my lower fairings where coolant takes heat from the engine and disperses it into the lower radiators

it doesn't always come on, just when it needs to

technically, aren't M8s liquid cooled then? The new Indian Challenger has a liquid cooled engine. How are they different?

I'm here to learn.
 
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Old Dec 1, 2020 | 12:24 PM
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M8 is air and liquid cooled
the water reaches only a portion of the cylinder head surrounding the exhaust valve

Indian and others have water jackets throughout

regardless both have temperature controlled fans that cycle as needed
BUT the coolant is always circulating
 
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Old Dec 1, 2020 | 02:37 PM
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Are you saying your 17 Street Glide is equipped with a Twin Cooled M8?
 
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Old Dec 1, 2020 | 03:09 PM
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Originally Posted by barneyboy
Are you saying your 17 Street Glide is equipped with a Twin Cooled M8?
ummm...it's a '17 M8 with radiators in the lower fairings....so.....yes?

seems like a strange question
 
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Old Dec 2, 2020 | 09:31 AM
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I thought street glide M8’s were oil cooled and didn’t come with lower fairings, but the ultra models came with lower fairings and were twin cooled?
 
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Old Dec 2, 2020 | 09:40 AM
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My understanding was that only CVOs, Tri Glides, and Limited models were dual cooled. My '17 Ultra Classic has factory lowers, but isn't dual cooled.
 
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Old Dec 2, 2020 | 09:50 AM
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Originally Posted by eighteight
M8 is air and liquid cooled
the water reaches only a portion of the cylinder head surrounding the exhaust valve

Indian and others have water jackets throughout

regardless both have temperature controlled fans that cycle as needed
BUT the coolant is always circulating
^^ that.

Originally Posted by dawg
I thought street glide M8’s were oil cooled and didn’t come with lower fairings, but the ultra models came with lower fairings and were twin cooled?
He has a CVO.
 
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Old Dec 2, 2020 | 12:36 PM
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Thanks.... the answer I was looking for helped a lot.

I was really just trying to get an idea of the difference.

yeah mine is a cvo... I assumed all Street Glides with M8 were twin cooled
 
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Old Dec 2, 2020 | 01:36 PM
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Old Dec 2, 2020 | 01:53 PM
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Originally Posted by CaffeineBuzz
yeah mine is a cvo... I assumed all Street Glides with M8 were twin cooled
Yup, you paid extra for coolant pump failures while us poor folks just get leaking oil lines.
 
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