Eagle Forged Stroker Crank CRACKED

jos51700 said
LOL at this thread. NONE of you have enough info to determine what caused the OP's breakage. NONE.

You don't know the alloy, you don't know the grain size, you don't know the damper condition, you don't know the material hardness, you don't know the material toughness. None of you can categorize the breakage as a fatigue fracture or an outright overload failure. You don't even know if the material is cast iron, cast steel, or Long Wang's House Of Secret Recipe's menu number 5. Any inclusions in the material? Don't know. Any corrosion? Don't know. Any casting flaws? Don't know. Any non-metallic alloying ingredients? Don't know. Post-production treatments? Don't know. Proper installation? Don't know. Proper handling during shipping? Don't know. Crank condition prior to install? Don't know.

You don't (in regards to the parts involved) know ****.

OK genious, then how about instead of going on a rage you enlighten everyone on why the crankshaft DID break?

jos51700 said
That is 100% NOT what 'those marks' are for. The forging is a piece of metal that's red hot, mashed into a crank shape by a massive hammer. The thick lines are flash (i.e. pieces of the original material that aren't going to be part of the crank. They are usually sawn off cold or cut off with a blade while still red hot. The forged crank is stronger because the material is 'worked' which strengthens it (for a variety of reasons). Think bending a paper clip or coat hanger; it's really hard to re-bend it in the same place, because the material has work-hardened in the bend. You don't usually see the flash lines on aftermarket cranks because they take great care to clean them up.

Pretty sure most people here know those marks aren't put onto crankshafts for the purpose of identifying them as cast or forged, but if the crank maker doesn't grind them off, they CAN be used for that purpose

jos51700 said
When you run a Chinese crankshaft, you don't know fuckall about what you just bought, other than that it's SUPPOSED to be what you wanted. I've see Chinese castings with gravel, bolts, broken end mills, and huge voids in them that you don't find until you machine them. There's ZERO accountability and ZERO U.S.-level Q.C until it gets here. After it gets here, VERY few people do material certs or anything else to verify it is what it's supposed to be. They take your money and they laugh all the way to the bank.

Not all Chinese crankshafts, seems to be a problem with Eagle cranks. Scat cranks are also sourced from China (at least the blanks are) and they don't seem to have those problems. But again, why don't you enlighten the rest of us as to what crankshafts ARE of good quality? Having a bad day or something? Geez, get laid... it might improve your mood.