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Discussion Starter · #3 ·
Yikes. How did you break that in? What oil are you running?
The very beginning of travel began to burn oil. For 12k topped up 4l. Came to the dealer and this is the picture. Oil 10-30
I apologize for the English, I write through Google translator)
 

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Discussion Starter · #14 ·
I'm not an expert but those grooves look severe. I wonder if the piston broke a ring or something. Is it the same on both pistons? Can these engines be machined and cylinder walls sleeved or do you just have to replace the cylinders?
The motor is running, just eating oil. It is not yet known what the officers will do.
 

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Discussion Starter · #16 ·
Is this a CRF1000 or CRF1100? The cylinders are different designs. The CRF1000 has a steel liner bore and the CRF1100 is a hard coated bore similar to Nikasil. The cylinder scouring looks like a typical over heating situation where the piston outgrows the cylinder or a low oil partial seizure. If not under warranty and it is a CRF1000 it can easily be bored if oversize pistons are available. It looks like a .25 mm overbore will clean this up. I have a cylinder boring machine and have bored thousands of motorcycle cylinders over the last 40 years.
Honda CRF 1100 2021
 

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Discussion Starter · #28 ·
Regardless of how it happened, you found the problem. I've seen this once before in an engine. Oil was contaminated during an oil change. I've seen it to a lesser extent by extended oil change intervals combined with hard use.

If you run any engine hard, hot, or both you need to shorten the oil change interval.

This kind of scoring can also occur if you run the engine hard without letting it warm up. Conversely, if you tamper with the thermostat and run the engine too cold, this can also happen. The piston and cylinder are designed to run at the same temp, if the cylinder runs cooler than designed, there will be excessive ring wear like shown. Haven't seen this because the engine was trashed, but this is why you service the thermostat in a boat motor on the regular.

Lots of variables, but hopefully that gives you some idea as to what might have happened.
My motorcycle has always been serviced in a timely manner, and in hot conditions, but the oil has been changed no later than 5k. Filled with Eni 10-30
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Discussion Starter · #30 ·
I assume you are looking at your cylinder walls through a spark plug hole with a scope/camera. If so it looks like a bucket of dirt went through your intake. Those look like serious grooves. What does the inside of your airbox look like. I’m surprised it runs, as bad as that looks. Have you measured compression or done a leak down test?
Didn't measure compression. Yes, it was checked with a digital endoscope.
What happened to the filters at 12500 km?
 

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Discussion Starter · #50 ·
If the bike has been dropped a lot and oil overfilled, you could get oil in the combustion chamber. Then a piece of burnt carbon could get between the ring and cylinderwall effecting compression and oil consumption.

Replace 1/2 quart of oil with marvel mystery oil, run for a few miles to get good and hot and replace oil. Good cleaner. Run a good quality fuel injector cleaner too. You might get some of that carbon dysolved off the rings and cylinder engine casings.
If the rings are not available, then no amount of decarbonization will help without disassembling the engine. The only thing that you can clean the combustion chamber, but the oil zhor will not stop. I repeat, zhor appeared at 360 km.
 
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