I decided to make a separate thread about this so as to not further derail the Ricochet thread. Sorry for the novel that follows.
There’s been a bunch of threads lately about people continuing to experience seized bearings on their YYF yoyos. Because I’d experienced this as well, I recently asked YYF Ben about it in one of the Ricochet threads because I was concerned that the Ricochet might have the same design issue. If you didn’t see it, here’s that back and forth:
To recap the issue – those stuck bearings, the squeak you hear on a lot of metal YYFs when you take them apart, that little ring of missing ano at the base of the bearing post – that’s all a product of the design of the bearing post, most likely a miniscule taper toward the base. What this means is that every time you open and close your YYF yoyo, the bearing is grinding across the bearing post, removing ano. Un-anodized aluminum pressed up against a bearing will eventually oxidize and seize, which would explain the prevalence of threads about seized bearings in YYF yoyos.
I was hoping someone else might bring this up, so that it wasn’t all coming from me, but since no one has, I’ll be the one to do it. I really appreciated that Ben took the time to respond to my question, and I’m very happy to hear that they’ve changed the design, but the answer I received perplexes me for a number of reasons. I’ll just stick to the most important of these.
CNC machines do what they are told to do. Though there are inconsistencies in machining, or production issues that result in bad pieces, the final product that a CNC lathe makes is dictated by the designer through a CAD program. What this means is that if an entire run, or runs, of yoyos have a tight or tapered bearing seat, then it’s fair to deduce that the tight/tapered bearing seat was designed into those yoyos – or a design issue, rather than something that evolved from production. And just for the record, the size differences on the bearing post that we’re talking about are miniscule – way less than the width of a hair, which means smaller than you can discern without magnification. But that can make a huge difference in the fit of a bearing.
Something like a tight fitting bearing post can certainly be a mistake on the part of the designer – and examples of both production and design issues like this from new manufacturers aren’t uncommon in the yoyo world. But in the case of YYF, a company that had a history of making awesome playing, trend setting yoyos with bearing posts that didn’t gall – the OG 888, the Grind Machines, the Superstar, etc. – I have a hard time imagining that it wasn’t an intentional part of the design, rather than an accidental production error. I’ll not speculate on why the decision would be made to build this into a design, but it seems to me that if a company intentionally designs a yoyo this way – and companies are certainly at liberty to design yoyos in whatever way they please – then it’s fair to expect a warning, like the warning Yoyorecreation uses, indicating that taking the yoyo apart will damage it. It also seems fair that the customers not be held responsible for this design issue. This is exactly what I suggested in a brief correspondence with a YYF representative - Patrick Mitchell – after I had moderated and cleaned up a thread where people had gotten angry about some problems they had with a YYF yoyo, despite Patrick having done all that he could to set things right with a replacement.
I really hate to feel compelled to post all of this publicly, but the prevalence of the problem seems to me to warrant people knowing that there is a design issue in many of the YYF metal yoyos that are out in the world that results in seized bearings and people show know that it is not their fault when they experience it. This problem goes back to at least 2009 – a DV888 I bought then definitely had it, and I had a brief correspondence with Ben about my experience with the seized bearing issue sometime that year. The message I received suggested that something I did, or my lack of knowhow, was to blame – not too dissimilar from what was posted today:
In any event, it’s great to hear that YYF has changed the design of their bearing posts to eliminate this issue, but it would also be great to know when the change occurred and to see YYF put a warning on their metal yoyos if the tapered/tight design remains the same on some of their line. I know most of the China-produced YYF yoyos have a month/year of production – is there a date you could tell us, Ben, that marks when this design change took place and which yoyos have been altered? Thanks for any info you can provide.