The cranks have stopped coming apart and/or spinning so wildly they ate oil pumps for a regular snack as they did during most of their first year. So the dinkuses (dinkii ?) changed enough to improve more than just the leaking head gaskets.
Nobodys' convinced me that anything's changed with the cranks either. What'd you hear from the dinkii on that? 
Hoist! 
They're not dropping like flies as they did when first released. So simple observartion suggests that either something is different or that all riders after mid-08 now only pull to 2400 RPM and never load the engine. As for the dinkii or anyone else convincing you of anything (evidence notwithstanding), we both know it ain't gonna happen 
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A number of things happened in ’07 that seem to coincide with the crank issues. In ’07 the Cruise Drive was expanded from the Dyna Platform to include all Big Twins. It seems that the new larger motor sprocket would easily max out the capacity of its shock absorbing compensator. This is evident by the sound made when the mechanical stops are reached at maximum travel.
When problems became evident in 2007, one of the first countermeasures was the torque smoothing calibration. This was intended to prevent the engine from pulling down hard at extremely low RPM. The resulting powertrain snatch would hammer the crankshaft off the compensator’s mechanical stops resulting in severe torque spikes at the crankpin, ultimately shifting the flywheel assembly.
One of the next countermeasures was the Isolated Drive System introduced on 2008 touring platform machines. The IDS is also offered as a retrofit for 2007 touring machines. This device absorbs shock loads generated from the powertrain, reducing stress at the crankpin.
Another countermeasure that followed in calendar 2008 was the high capacity compensating sprocket. This device is original equipment on select machines which are not equipped with the IDS, and is also offered as an accessory. It comes with a cool looking thrust washer that you can put a chain through and wear around your neck if desired. Consider picking up an extra thrust washer for that; chicks dig it.
Regarding other internal countermeasures; the buzz around the water cooler is that the extreme interference fit of the crankpin into the flywheel doesn’t tolerate being disturbed after it has been assembled. My understanding is that if the joint is moved after assembly, even for truing, the integrity of the joint will be compromised, reducing the torque capacity of the assembly.
Somewhere inside a pocket protector there is a calculation based on production variables that results in a substantial number which is used to specify the trueness of this assembly. So far it seems in practice that this number is not representative of the actual assembled component. It would be interesting to have a look inside her pocket protector for some additional insight on this.
Another thing heard was that plugs are good for about a 5% increase in the joint’s capacity, and that welding severely compromises the joint, leaving just the weld to support it. Having used a welder to shrink countless bearing races and an occasional valve seat, this makes perfect sense.
As always, this chatter is JMHO.
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Topic: Top end "clacking" sound (Read 56613 times)