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2021 M8 114 w/53K - Borescope

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Old Sep 23, 2024 | 05:01 PM
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Default 2021 M8 114 w/53K - Borescope

I recently acquired a borescope, and decided to take a look inside my bike's cylinders.
Here's a video of the front cylinder:

Rear cylinder:

This is a 2021 FLHTK with 53,000 miles. Is this normal? I think I see some cylinder scoring and a bunch of carbon. This bike is completely stock. I still have ESP. Should I try to get my dealer to do anything?

 

Last edited by David Crowell; Sep 23, 2024 at 05:04 PM.
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Old Sep 23, 2024 | 05:20 PM
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The rear looks like it ate a bit of water.

Front looks "normal" for a stock engine that has the crankcase breather feeding into the intake.
 
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Old Sep 23, 2024 | 08:13 PM
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link for borescope?
 
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Old Sep 23, 2024 | 10:14 PM
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Originally Posted by Vec
link for borescope?
Amazon Amazon
 
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Old Sep 24, 2024 | 07:16 AM
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Divert the breather to atmosphere and use some Seafoam in the tank and ride..
 
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Old Sep 24, 2024 | 08:34 AM
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have fun with that warranty thingy
they will consider it normal wear and tear and/.or maintenance
especially with that many miles. on the ole irons, it was considered normal for 1 qt per 500 miles, the evo is better but i do not remember their turning point.
 
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Old Sep 24, 2024 | 06:19 PM
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Looks like you never ran it the limiter..
 
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Old Sep 25, 2024 | 12:08 PM
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Since I was there, I replaced the plugs, checked the air filter, replaced one plug wire that was rubbing on something, and got it back together.

I'm going to consider venting the breathers through a catch-can. If I do, I'll ride a few thousand more miles, and scope it again.
 
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Old Sep 28, 2024 | 04:38 PM
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Ride it like you stole it. That will also help otherwise a manual decarbonization may be in your future.
 
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Old Sep 29, 2024 | 03:39 PM
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Looks like detonation on rear cylinder, thats why its cleaner. Not destroyed yet but could use a better tune.
I would ask them to look into it as its totally stock, if it was mine I would be checking injector on that cylinder .
 

Last edited by xcbullet; Sep 29, 2024 at 03:42 PM.
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