Showing posts with label ProFLEX. Show all posts
Showing posts with label ProFLEX. Show all posts

18 May 2018

Without Air Or Tubes, In 3D.

Three years ago, "The Retrogrouch" wrote about one of the most interesting and enigmatic companies in the cycling world.

Zeus probably came as close as any bike manufacturer to crafting all of the parts for its bicycles.  Of course, they didn't draw the frame tubes, which were usually Durifort, Vitus or Reynolds.  But they, or one of their subsidiaries did  make all of the other major parts, except for the tires.  But you could still ride Zeus tires on your Zeus bike.  How's that?, you ask.


Well, there was a company in the US called Zeus that made them. But they weren't the kind of rubber someone riding a Reynolds 531 frame with Zeus 2000 components would have wanted.  The appeal of that tire, the Zeus LCM, was found more among novice commuters and folks who didn't want to get their hands dirty or scratch their just-enameled nails. (I can understand that!)


Those tires were airless and didn't go flat because they were solid polyurethane rubber.  I tried them for a half-century and a few days of commuting. I wondered whether I had just experienced what it was like to ride a "boneshaker"!  


As so often happens when a new product comes to market, people think the idea is new when, of course, it isn't.  And when it disappears, it will probably return and have another generation of consumers believing they've just witnessed the most wondrous innovation.


Well, it turns out that the airless tire has been revived during the past few years.  Three and a half years ago, The Retrogrouch wrote about a new crop of such rim coverings. 
They were not solid, like the Zeus, but like other offerings that preceded them, they had solid inner tube-like inserts.  

Now a German startup company, ProFLEX, has created its own version.  This one does not have an insert but, unlike the Zeus, it is not solid rubber.  Instead, it is supported by a complex honeycomb-like structure inspired by a car tire Michelin introduced last year.  That network mimics alveolar structures like the air sacs of lungs:  solid on the inside and more flexible on the outside.  


(Or, since we're talking about Michelin here, we could say it's the inverse of a baguette, which is crunchy on the outside and chewy on the inside.)


The ProFLEX has one more thing in common with the Michelin tire:  It is 3D printed.



ProFLEX tire


Although I am not sure I would switch over to such tires, I would be curious to try them. I wonder whether their ride is more akin to that of pneumatic tires (most likely heavy ones) or solid tires like Zeus.


None of these airless tires, by the way, should be confused with tubeless tires, which are filled with air and can therefore be flatted.  I know:  Bill and I stopped to help a fellow who'd just been sidelined with his tu
beless tires.