Junk is junk, except when it's Harley selling the junk. Then it becomes "normal" when they either don't know how to fix it, or more likely don't want to spend a few bucks to fix it.
The change from a dual tapered roller bearing set (Timken) on the drive side of the crankshaft is not the root cause of the increased failure rate of the '07 and later cranks. The Timken set was eliminated for 2003, and the 2003-2006 engines didn't see increased rates of scissoring (twisting). Only when H-D changed the design of the flywheels and output shaft for the '07 ('06 Dyna) did the stuff hit the fan. There were many major and total failures on the '07's, and while the reports of major failures has dropped in the following years, the amount of runout reported by those having their cranks measured is still significantly higher than the previous generation Twin Cams. This does not bode well for oil pump life, even if the crank doesn't fail or get worse over time.
BTW, if you really want a Timken dual roller bearing set, you can pay H-D for the parts to convert your '03 and later engine. Folks who drag race or who like to do burnouts to impress the crowd at the local bar might gain something from the change, but regular folks probably don't need to worry about it. On the other hand, if you plan any major bottom end work or major power increases, having the crankshaft upgraded will be worth the expense. Either have the existing part trued, balanced, and welded/plugged, or buy a good replacement from the aftermarket. At that time, if you want a Timken go ahead, the additional expense won't be so bad since you already have the bottom end torn apart.
Oh, just in case anyone thinks this is just a 110 problem, think again. The same crank is used in the TC96, the '07 and later 103, and the 110.
Jerry
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Topic: Crank upgrade (Read 2168 times)