Blow by

[chchnick]

Pulled the pipe off my 300 at 20 hours from new, this is how the piston looks. It was jetted for me and I run 50-1 belray h1r. What do you guys think?

[stabak]

I think its ok, I have exactly the same hours piston and looks the same

[Zman]

IMO it looks like you need to replace the piston and rings, because you are getting combustion past both rings.

[memphis2857]

Looks to me like that is some nasty oil you are running! How is your jetting? There is an awful lot of carbon and oil gunk build up, especially for 20 hours. I bet your powervalve is a mess


Sent from my iPad using Tapatalk

[elemetal2]

Could all that burned oil below the rings be from scavenged exhaust? The bottom of the piston should be much cleaner but I'm having a hard time believing that much blow by with so little run time......

Better go check mine soon.....

[Dunc]

The rings can get gummed up with build up of deposits causing blow by, looks like allot of carbon for only 20 hrs! What does the plug look like?

[chchnick]

Further down the the piston is clean as a whistle, top of piston looks pretty good as well. Running belray h1r at 50-1 and plug looks a tad rich.

[Dunc]

I would look at running leaner for a while and recheck, your dealer should be best person to advise jetting etc... May be try a different oil 1st and then look at mixture, motor should be sweet for 100hrs before needing to do anything to it. How does it run?

[memphis2857]

Here are a few shots of mine. Bike is a 2011 with 31.7 original hours. I run Motul 800 at 50:1. Jetting is 178m 42 pilot and NEDW clip 2. Notice you can still see the coating on the piston and there is very little blow by between the two rings. Also the exhaust port is nice and clean and dry.


Sent from my iPhone using Tapatalk

[chchnick]

Does look like it's running rich compared to your pics, she runs really well, doesn't bog and response is crisp. The exhaust port on mine does look quite wet in comparison, but I have little to no spooge out the silencer