Thread: like that?
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Old June 3rd, 2021, 08:47 PM   #17
Triple Jim
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Name: Jim
Location: North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

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MOTM - Oct '18, Aug '17, Aug '16
Quote:
Originally Posted by ducatiman View Post
"compression tests done at 6000 mile intervals"

Huh? I'm guessing you really meant *valve clearance* checks?
Right. @thrasherblue, a failed compression test shows the result of valves that are so far out of adjustment they they're not closing. You need to check the valve clearances at regular intervals and adjust them to spec to prevent them getting so far out of adjustement that they don't close. Once they're not closing all the way, damage is starting to happen. When a cylinder fires, if a valve is not quite closed fire squirts past the valve, wasting some of the energy, but also eroding the metal of the valve and the seating surface it should close against.

Checking them involves taking off the valve covers and using feeler gauges to check the clearances between the valves and the cam lobes that are epening them. It's in the manual, and also here: https://faq.ninja250.org/wiki/How_do..._the_valves%3F
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