"That's why bikes used to use chains." (?) LOL! I fail to see what a "chain" has to do with that screw coming loose or how it could have prevented it. I'm loving this thread and the unintentional humor. It really shows the ilk of this new breed of riders today.
Really? This "tale" of biker bars and Harley lawyers has been circulating since before most of you were born. They only litigate when someone uses the name HD or the bar and shield logo in thier name or on their main sign out front - and rightly so, otherwise "Harley" bars are great for their business. This internet is nothing more than a glorified Inquirer.
Seems to me this is the kind of malfunction that can oly be seen in hindsight. I'm not sure you can second-guess everything. When the belt guard falls off, you notice, there is only one screw. Not something you would go looking for.
Well, I'm the "rider". Arguably an idiot. Arguably, this is not the only problem here.
I sometimes do my own oil changes and install accessories; however, you're right, lately I usually pay a professional mechanic to complete most of my bike maintenance. Is that incompetant? I don't think so. I am a professional engineer, have hot-roded bikes and cars since the mid-1970's. I have built a V8 conversion to a hot-rodded Corvair in the 1970's from the ground up. Was this loose guard partially my error? Absolutely. Have YOU ever made an error? I don't know you, but I presume so.
I had done a visual and hands on inspection several days before and again that day. (Remember I was concerned about the rattle too.) Do you tear down your bike and retorque it daily? Not if it's a daily rider, instead of in racing.
Obviously, I missed the "root cause" problem. I have 20-20 hindsight too. It is embarrassing that A) I am a contributing factor to the problem of the belt guard falling down and getting jammed between the belt and pulley.
However, I believe B) the mechanic that performed my state vehicle inspection two weeks earlier was a contributing factor, and C) the original design is flawed to have no redundancy to mitigate this risk. Critical fasteners should have redundant locks or clips when possible.
Is that the only maintenance since the V-Rod was built 6 years ago? Absolutely not. This bike has over 19,000 miles and has been ridden from PA to NM and back. My Dresser has over 49,000 miles since 1999. They both get regular service. The soft Z-rated V-rod tires wear-out in around every 5,000 miles, so those wheels come off-and-on AT LEAST that often.
This WAS a maintenance issue that was more critical BECAUSE of a higher-risk design. This can easily be argued as a design FLAW; even though, it is subtle. As engineers and designers, we should be responsible to conduct DFMEA analysis and mitigate high-risk areas when practical. In my opinion, this focus is the real value of this discussion in Design News. I don't like about this column being called "Designed by Monkeys", after all I am also an engineer trying to make good design choices which are sometimes a trade-off.
I have sent Harley Davidson a letter documenting this specific concern. I am not trying to disrespect Harley Davidson, sue them, or otherwise injure them. However as actuarial studies will statistically support over time, time high-risk areas will fail and lead to fatalities if not addressed. As a reputable company, I trust that they will address this issue when the best solution is defined.
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