I know there has been a lot on this forum about the 88 Twin Cam Engine Cam chain tensioner failures etc. (I hope the forum Town Fathers let my post run) Here is what I am intrigued about. What actually is the cause of this? Your imput would be educational and informative and personal as well. Having read many accounts it seems to me the oddity is that it is the randomness of it. Or no exact amount of mileage on the machine when these wear out. Case in point...I talked to a gent that just checked out his '04 Roadglide with 54K miles. His tensioners were only half worn out. Yet at 30K miles my brothers '03 Ultra's were shot and had to be fixed on the spot. With the history being what it is, could this be the cause. In production back then some actual chain cams got out that had perhaps "minute burrs" on them? Hence the rub plates would wear quicker....Or Perhaps the material the rub plates were made of a poor quality? Working in Manufacturing many years...even the best quality control system is alway less than perfect...Just ask Toileta or Firestone tires to name some more resent. Companies can try to do their best...yet "things get out". Hope to hear some feedback and personal views and observations on this matter of "CAUSE", of failure?????