R3 Forged Crank

Photos above of Todd Nelson's brand new R3 crank from Triumph. Easy to see that it is forged, and also has fillet radii in journal corners. Jerry will take photos of the stock rods when he gets to them, but no doubt they are also forged just as Scott (Warp9.9) reports. This is very good news... with forged pistons and Carpenter valve train the R3 should go to 9000 RPM! You guys have a great Summer!
 
While I'm no expert on the subject, but judging from the casting mold separation lines on the counter balances, that crank appears to be cast not forged. I've not seen those lines on a forged crank. Comparing the pics to a known forged crank, as much as I'd like for it to be forged, I'll have to disagree with you on it.
 
Wrong.


The casting process results in greater control of the net shape in the forming process, which is evident from visual clues in the finished crankshaft. Looking at the counterweights is a dead giveaway. A forged crank's counterweights (left) will generally have a rougher look with rounded edges, while a cast crank (right) by comparison will show sharp, well-defined edges.


A second visual check can be made by viewing the parting line that defines where the casting core or forging dies separated. A cast crank will have a thin, sharp, and straight parting line (left), while the parting line on a forging will be wide and generally less defined (right).


For the visually challenged, a forged crank can be identified by ear. A forging will ring like a bell when tapped on the counterweight with a steel hammer, while a casting will give a dull thud.
 
Nice !!! Also notice the cast crank has machined lobes on the face and the forged does not!!
Happy hunting on 9 grand!:D

mutt
 
you are correct hombre on the hammer tap, I learned that back in machinist school! as demonstrated by the teacher! definate ring on the forge, dull thud on the casting!
 
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