Classic & Vintage - Plastic bike.

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C_LOGAN
07-01-07, 12:39 AM
Quite an interesting read. The first and only plastic bike ever to be made - said to be stronger than steel because of its design.
Full document here: http://www.firstflightbikes.com/newpage5.htm
http://www.firstflightbikes.com/plstbke.JPG
Read the document - honestly sounds like bs... Can withstand a beating with a sledgehammer, can hold the weight of a fully loaded car on top of it, can withstand high temperatures.... has self lubricating properties and never requires maintenance - with a plastic chain......
And another one that actually made it into production:
http://en.wikipedia.org/wiki/Itera_plastic_bicycle
East Hill
07-01-07, 07:08 AM
Makes me wonder how many of those Itera cycles are still on the road. I would think that environmental degradation has rendered many of them unsafe.
East Hill
le brad
07-01-07, 08:09 AM
it needs these (http://www.hedcycling.com/wheels/superlitedisc.php)
Sammyboy
07-01-07, 08:41 AM
I've seen Iteras on UK eBay - not that model, but townie ones, still in running condition.
Not so far fetched, just ahead of it's time...
http://en.wikipedia.org/wiki/Carbon_fibre_reinforced_plastic
bikerosity57
07-01-07, 02:23 PM
Many of you are too young to remember, put about the same time there was a company selling plastic seat posts, and they used all the same BS in their add too. They looked just like a Campy two screw Record, only some "space age" white plasric. We put one on my brothers bike, and I took it for a ride: I just got out of the drive way when SNAP!!!! The damned thing broke within one minute! Broke like a bone with a big sharp projection coming out of the frame. Very scary, and very stupid. I would imagine something similar happened tp many of these BS bikes as well.
East Hill
07-01-07, 03:36 PM
Not so far fetched, just ahead of it's time...
http://en.wikipedia.org/wiki/Carbon_fibre_reinforced_plastic
I think I trust the modern version a bit more than the older version. As bikerosity57 said, a suddenly snapping bit of plastic could have some very sharp bits :eek: .
Sammyboy, that's interesting that you've seen Iteras still for sale on eBay. I'll have to dash over there and take a look. Perhaps only the townies survived?
East Hill
HDFACTORYCERTIF
07-01-07, 05:36 PM
I often work plastics in my machine shop and my friend has a plastics mold shop here.
I believe they have made many advancements in the last thirty years, I would wonder of the durability of a bike so old. I am not sure of if this is a new bike or an old one.
Looking at the bike, I am struck by the cost of the molds and the size of the molding machines required to form the frame and fork.
The modern plastics are formulated by blending beads of it, then its melted and pushed under extreme pressure into the mold. I find it interesting.
They do make the Glock handgun frame this way, with steel inserts where needed. I prefer the Colt Single Action Army however, let em rust.
Don
mastershake916
07-01-07, 05:56 PM
Well there was this really cool bike that could be assembled and reassembled into another bike.
Is was a child's bike, and had the property of a building toy, and if I remember correctly, it was marketed in another country and it's name translated to "ant".
Many of you are too young to remember, put about the same time there was a company selling plastic seat posts, and they used all the same BS in their add too. They looked just like a Campy two screw Record, only some "space age" white plasric. We put one on my brothers bike, and I took it for a ride: I just got out of the drive way when SNAP!!!! The damned thing broke within one minute! Broke like a bone with a big sharp projection coming out of the frame. Very scary, and very stupid. I would imagine something similar happened tp many of these BS bikes as well.
Those were the Shiba-Western seatposts, made of that miracle plastic - Lexan. They made a saddle rail assembly out of it also. Well, at least they offered was a lifetime guarantee against breakage.
As to the plastic bicycle, it looks great on paper, until you consider the diisadvantage. Just think of your old plastic Simplex derailleurs and shift levers. Flexy as H-E-double hockey sticks. Not the most endearing property for a bicycle.
group105
07-02-07, 06:15 AM
Many of you are too young to remember, put about the same time there was a company selling plastic seat posts, and they used all the same BS in their add too. They looked just like a Campy two screw Record, only some "space age" white plasric. We put one on my brothers bike, and I took it for a ride: I just got out of the drive way when SNAP!!!! The damned thing broke within one minute! Broke like a bone with a big sharp projection coming out of the frame. Very scary, and very stupid. I would imagine something similar happened tp many of these BS bikes as well.
The word TORQUE gets thrown around a lot these days.
You can tweak a carbon seat post if you are "dedicated".
repechage
07-02-07, 06:35 AM
I believe they have made many advancements in the last thirty years, I would wonder of the durability of a bike so old. I am not sure of if this is a new bike or an old one.
Looking at the bike, I am struck by the cost of the molds and the size of the molding machines required to form the frame and fork.
The modern plastics are formulated by blending beads of it, then its melted and pushed under extreme pressure into the mold. I find it interesting.
They do make the Glock handgun frame this way, with steel inserts where needed. I prefer the Colt Single Action Army however, let em rust.
Don
Glass fibre is used often now, as is chopped graphite. Way back I saw in one of the Bicycling! mags, the articles or adverts from time to time on the "plastic bike", a direct translation from steel to plastic is a bad idea, the European bike referenced is better as is addresses the loads better.
In addition to the stupid plastic seat posts, which also used an insert (like the Peugeot UO8) to reduce the diameter (!?) there were also plastic headsets for the super weight weenies. The first durable application of plastic I saw were the Skyway tuff wheels, for the emerging BMX crowd, now they did use glass reinforced plastic.
Sammyboy
07-02-07, 06:41 AM
I often work plastics in my machine shop and my friend has a plastics mold shop here.
I believe they have made many advancements in the last thirty years, I would wonder of the durability of a bike so old. I am not sure of if this is a new bike or an old one.
Looking at the bike, I am struck by the cost of the molds and the size of the molding machines required to form the frame and fork.
The modern plastics are formulated by blending beads of it, then its melted and pushed under extreme pressure into the mold. I find it interesting.
They do make the Glock handgun frame this way, with steel inserts where needed. I prefer the Colt Single Action Army however, let em rust.
Don
What you describe is injection moulding, which has been around a long time, certainly since the late 70's. The formulation of the polymers may have changed, however.
Those were the Shiba-Western seatposts, made of that miracle plastic - Lexan. They made a saddle rail assembly out of it also. Well, at least they offered was a lifetime guarantee against breakage.
As to the plastic bicycle, it looks great on paper, until you consider the diisadvantage. Just think of your old plastic Simplex derailleurs and shift levers. Flexy as H-E-double hockey sticks. Not the most endearing property for a bicycle.
Yep, if steel's real than plastic's elastic!
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