KrZy8 Engine Autopsy results - first FJR cylinder failure?

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dcarver

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2019-08-16 KrZy8 Engine Autopsy Results

Over 7 years ago, the OEM engine was replaced. Water in cylinder. Assumed it was the head. Gave engine to FjRay to autopsy. N20sx, Carlo, needed gearbox parts. Ray gave engine to Carlo who found this..

This pic taken when we replaced the head gasket at Hal's house.

First known FJR 1300 cylinder failure?

Carlos picture.

So there it is.

This bike had sucked dirty air for years due to shop not plugging evap cannister lines when evap box was tossed after a deer strike.

Still, this look like more than dirt particulate matter.. JSNS..

No idea what got in there..

First FJR 1300 cylinder failure?

 
Well, that explains the problem. The canister line is large enough for very small gravel to get sucked into the intake box, resulting in this. Ouch.

I think that deer you hit got it's revenge....

I'm thinking we didn't see it as the piston was at top - I do recall a knarly carbon build up we were scraping out of the head.

 
Canister isn't connected to the air intake box.

Vacuum lines from throttle bodies 1 and 4 are teed together and the tee's third hose connects to the canister.

Any foreign object would have to be quite small to pass through the vacuum lines and hose connections on the throttle bodies.

But cylinder 1 is damaged and throttle body 1 provides vacuum for the canister.

 
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