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Plastic penny-farthing
(11 posts)-
Posted 11 years ago #
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Correction: it' a carbon penny farthing. "The forked frame is built from carbon fiber made with BASF's Baxxodur epoxy resin".
Or should we just refer to carbon road bikes / MTBs from now on as plastic bikes?
Posted 11 years ago # -
"Or should we just refer to carbon road bikes / MTBs from now on as plastic bikes?"
I believe some people do...
OK, this is the 'proper' Plastic bicycle...
Posted 11 years ago # -
The fatal flaw with plastic bikes: "Where metal bends, plastic breaks. "
Posted 11 years ago # -
Blatant untruth when I was a child, was that if you bent the wheels on the Blue or Red Raleigh BMX Burner you could put them in the freezer and they'd straighten. The things we believe as
adults... aherm.... children, yes, the things we believe as children!Posted 11 years ago # -
Posted 11 years ago # -
"Carbon" is just a common name for Carbon-fibre Reinforced Polymer. It's an epoxy (or similar) resin binding together a structural layering of graphite fibre weave. It's pretty similar to papier maché in concept. And very much like the earlier "Plastic" of "plastic cars", which were of glass-fibre reinforced plastic (fibreglass). Which is I believe why TVR and Lotus cars smell of glue.
They've been building fairly large warships out of GRP for decades, it's a lot more flexible and less brittle than Carbon. HMS Tupperware was the first and was built in 1970 (as HMS Wilton, but sailors have a better sense of humour than that). Before that they had to build minehunters out of plywood and aluminium which does not make for a very long-lasting, tough vessel. Same is probably true of bikes. Not sure if anyone ever built a GRP bike. Or a papier mache bike for that matter.
Posted 11 years ago # -
I believe some people do...
'Plastic and soot' is the common term I think. But it's true, carbon fibre is just very hi-tech plastic. Just like Specialized's 'M2 Metal Matrix' was just posh metal with bits in.
Where metal bends, plastic breaks.
Not necessarily true. An impact that would cause a nylon part to bend might break an aluminium equivalent. Strength and stiffness aren't the same thing, and vary with temperature too. A contributing factor in the Titanic's demise was brittle fracture brought on by the near-freezing water temperature (along with sulphur inclusions, hydrogen cracking and so on).
Before that they had to build minehunters out of plywood and aluminium which does not make for a very long-lasting, tough vessel.
Project Habbakuk and Pykrete FTW. :)
Posted 11 years ago # -
It's no wonder the Itera bike was a failure - who would lock their bike up unattended in public? You wouldn't just come back to a buckled wheel, the whole bike would be a melted lump!
Posted 11 years ago # -
I was hoping to see how a 39" fixed wheel coped with descending, but they cut the video just before the rider started.
Posted 11 years ago # -
@Focus, I think the overwhelming beige-ness may have put some folk off. It was the 1970s though and beige was okay...
Thing is, the child seat and bike bin panniers look pretty contemporary.
Posted 11 years ago #
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