I cam across a few other potential issues; are these legitimate claims?
The engine is not sufficiently secured to the frame causing weaving, wiggling, wobbles and rear wheel steer. There is a fix. ProgressiveSuspension.com makes brackets you can install yourself to stop the high speed wobble. True-Track also makes a fix for Dyna, Low Rider and Touring models.
The biggest problem is the poor design of the cam chain system. It still uses "shoes" riding on the cam chains that can still wear out, even with the new hydraulic tensioning system, for that is not a true fix. What is the problem? The shoes rub against the two chains and the shoes wear out. When they do there will be metal to metal contact and this grinding creates metal shavings that creates a catastrophic engine failure. What is the fix? You can purchase a gear set that eliminates the cam chains and shoes. Harley-Davidson should, in my opinion, make this a standard fix and not an after the fact option. If you can't afford to install the gear system, then you need to disassemble and inspect the inner and outer shoes every 15,000 miles or risk total engine failure. The shoe material can also clog the oil pump totally destroying the engine.
The shift drum is operated by a spring loaded awl and if this spring fails, and they do fail, the spring falls into the transmission gears and horrific damage takes place.
Another terrible problem all Twin-Cam engines have is the dreaded "crankshaft slip." A perfectly new bike with low miles can suddenly begin vibrating so badly it makes riding no fun anymore, even if the engine is rubber mounted.
As the 88 twin cam engine evolved to the 96 cubic inch a strain developed on the gears. In the year 2007 the inner bearing race was upgraded due to bearing failure. In the year 2010 the fifth gear was changed to a reverse-helical gear to neutralize the side load on the bearing. What does this mean to the average rider? It means if you hop up the engine on any twin-cam engine you risk a major transmission failure. So, you need to purchase and install a fifth gear and bearing/shaft update kit if you ride the bike hard (which many riders do). The race on the shaft can move, which lets the seal leak and the bearing walk/wobble more than it should accelerating wear and fail. Some riders have found this bearing failure twice in 40,000 miles. Mostly hard-ridden stock 88 and 96 will fail along with those with souped-up engines (pistons, cams including crankshaft long-stroked engines). But the new 103 cubic inch twin cam are not immune to transmission failure even though they have the updated kit installed at the factory.
The 88 cubic inch engine ran hot and at the high limits and the 96 cubic inch engine runs hotter yet which is not good for the engine. The 110 cubic inch engines run exceedingly hotter and so much so a class-action law suit was filed against Harley-Davidson from riders being burned from the engine heat (mostly from the rear cylinder near the rider's thighs).
The Twin-Cam bikes 3-phase 45 and 48 amp alternators burn up or they will burn up other electrical components. There is a cure. Replace the entire alternator with a new 50 amp unit manufactured by CycleElectric.com
To replace a worn or perforated belt the entire primary chain case must be taken apart along with the bike's swing arm. It is expensive to replace a belt or the transmission drive pulley. Most riders don't even think about this until the day comes they have to replace the belt and find out it will cost them $1,000.
