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Is this normal? I just got my first bike and with only 1300 miles figured all should be good. It runs great by the way. But when I pulled the skid plate off I noticed these strange lines on the crankcase. Is this from the manufacture process or is this a big problem?
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Those look like paint cracks to me. Looks like maybe the curing process didn't go as expected. I don't think they go beyond surface level, but that is only what I can surmise from the pics. You should be able to tell if they go any deeper than that by feel. You could even flake off some paint if you really needed to to verify and then touch it back up. My 2 cents.
 

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My 2009 looks exactly the same. I was unsure if they were anything to worry about or not so I cleaned the area with brake cleaner and then put a few sheets of paper under the bike. Then I fired it up and let it run until it was good and hot to check for leaks. No leaks at all. Evidently, it's just the way the paint dried under the casings.
 

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Glad you guys spotted that condition before I did. I would have fully freaked out, had I seen that without reading this first.
 

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Those are flaws in the casting, The die cast process over time develops heat check crack in the die. then when the casting is poured these flaws transfer to the finished product. the cracks are actually raised lines on the case that you are looking at
 

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Those are flaws in the casting, The die cast process over time develops heat check crack in the die. then when the casting is poured these flaws transfer to the finished product. the cracks are actually raised lines on the case that you are looking at
I used to work in an aluminum and zinc die casting plant as a manufacturing engineer. It is correct that they are heat checked dies (the dies crack like cracked skin). Those marks won't cause any problems only the finish looks terrible. You can only imagine how many engines those dies have made since 1987. Actually, I'm sure they've changed out dies a lot since then. When they get bad they'll get new inserts put into the dies.

In die casting though a ram (piston) slams the molten aluminum into the dies. The molten aluminum is not poured but rammed with about 2500 psi IIRC. The metal is poured into a funnel into the very long cylinder then the piston goes slowly to cover the funnel port and get the metal around the piston then it slams the metal with a fast shot. There's a lot of science to it to get it so it's not super porous. On our aluminum machines the piston was about 4" dia and the cylinder was about 5' long. The reason I said IIRC is that it's been 25 years since I did that as most die casting shops closed not long after that and moved the machines and dies to China. Glad I did a career change when I did.
 
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