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kawashima
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 Posted: 15:33 - 16 Jan 2016  Post subject: what is good about spoke wheel of on-road bikes. |
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I like cast wheel better than spoke wheels for on-road bikes.
They are easy to clean. No adjustment needed.
what is good about spoke wheels?
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kawashima
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| Posted: 16:05 - 16 Jan 2016 Post subject: |
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| Snod Blatter wrote: | Technically they are lighter, so there is less unsprung weight and their gyroscopic effect is less so the bike may be less stable/more flickable. I've never really noticed a difference though. Anecdotally, in my experience the "give" they provide with the flex of the spokes when you are leant over makes for a very smooth and reassuring ride, though this is surely a false sense of security and the spokes are merely hiding the bumps from the rider and surely not doing anything to improve the grip available.
Overall I really like them, but they're definitely harder to live with from a care and maintenance perspective. |
Thanks Snod Blatter, I didn't know well about the differences from functional and technical view point at all.
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Kickstart
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c_dug
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Posted: 16:33 - 16 Jan 2016  Post subject: |
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On a bike like the SR you posted, spokes are pretty much just for show.
On a serious off road bike they tend to cope with abuse better than cast wheels, and minor damage is easily repairable (for instance changing a broken spoke) compared to a cracked or dented cast wheel.
Spoked wheels rot quite badly in my experience if they're not looked after. Cast wheels are more a fit and forget type of thing. It was quite common to change the standard spoked wheels on the TDR 250 for cast items from the TZR for this reason (excuse the teenage me):
https://i235.photobucket.com/albums/ee81/paddy2007dug/TDR250/DSC00833.jpg
https://i235.photobucket.com/albums/ee81/paddy2007dug/IMG_0908.jpg
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kawashima
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| Posted: 17:06 - 16 Jan 2016 Post subject: |
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| Kickstart wrote: | Hi
Not sure on weight, but will also depend on what material the cast wheel is made from.
Suspect for off road use the main reason is that they can easily be straightened when lightly bent
All the best
Katy |
I understand weight difference by its materials. My bicycle (for daily use) has stainless rim & spokes, cheaper model has aluminium rim & spokes, former one has better durability and less rust but heavier than latter one.
To make it light aluminium should be better, but I often feel sad when I find old used bikes like GB400TT with picture of corroded aluminium rim wheels.
I don't like rotted spoked wheels either(on used bikes on sale).
I didn't know this conversion to cast wheels, That TDR looks very different and cool!
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kawashima
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kawashima
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| Posted: 17:30 - 16 Jan 2016 Post subject: |
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I saw enfield with cast for the first time  I like this too 
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| Posted: 20:21 - 16 Jan 2016 Post subject: |
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Triumph put spoked wheels onto a rim that takes tubeless tyres on their 'off road' versions of bike.
As far as I understand it, nowadays it is either looks, on an Enfield/WR, or practicability on an off road. A spoked wheel with a good stainless rim will take way more abuse than a mag wheel. Spokes flex and don't break, as do the stainless rims.
https://www.mcnews.com.au/wp-content/uploads/2013/12/Tiger_Explorer_1024.jpg
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Posted: 21:08 - 16 Jan 2016  Post subject: |
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A wire spoked wheel holds the rim in 'tension' on the spokes, which is very efficient use of metal, as the 'load' is trying to stretch it, and it will have to stretch a lot before it will snap.
In compression, a 'member' under load will try and bend to comply with the applied force, so it has to resist both compressive forces and bending forces, so to carry the same load force a spoke in compression, will tend to have to have a thicker 'section' to resist bending.
In theory, this means that 'within certain limits', its possible to make a spoked wheel that is lighter and or stronger than a cast one.
In practice, you can make a cast wheel that's lighter and stronger than a wire-spoked one....
I had to shift some old TZ wheels the Thursday, one pair were original alloy rimmed wire-spokes, the other were an awful lot stronger and lighter die-cast magnesium.... Original Swindon Dymags actually, which they were going back to for refurbishment and crack analysis, hinting at an issue with them... main one though, that whilst a lot lighter, and stronger, they are also a lot more expensive, and less durable. As said, the Dymags are prone to 'fatigue' cracking.
I was actually shifting them to get at another wheel, this one for my old Montesa trials bike.. that DID have a fatigue fractured hub! Fucker went on me on the last but one section of an event a few years back, on an obstacle on a steep climb! NOT NICE! But, being retrieved to see if the hub can be salvaged.. which s probably another story.
On a race track.. wheels tend to support much higher 'peak' loadings, certainly on modern bikes with the grip their tyres offer and the torque being out on them from 100+bhp engines, but on a dirt bike, you don't often get much with much over 50bhp, and tyres don't have anywhere near the grip on loose dirt as delugrip tarmac, so they will rarely generate anywhere near the same levels of loading, so the wheel need not be as rigid to support it...
On dirt, though, while the 'peak' loadings might not be as high, 'cyclic' loading, how often load is put on a and take off and put back on again, is likely to be greater, as the wheel takes a 'pounding' on every bump and jump, this is more likely to cause a 'fatigue' fracture on a cast wheel, making them less durable.
In trials, I run around 3psi pressure in the back tyre, its almost 'flat' before I launch it off an obstacle, so that the rim is taking almost all the landing force directly with little or no 'cushioning' from the tyre... I had a pair of tubless tyres on it at one pt that have slightly stiffer carcasses and can be run at zero pressure.
Again, the peak loading might not be particularly high, but the rim taking the full impact almost directly, the 'shock' load can be pretty severe. Here the lack of rigidity can offer some 'compliance' that a cast wheel holding the rim in compression, rather than tension lacks, again helping reduce fatigue stresses.
Its also more likely to result in a 'catastrophic failure'... when the hub 'went' on my trials bike wheel, the crack started at one of the sprocket bosses travelled through the hub, and stopped at one of the spoke eyes... there that bit of metal stopped.. had it been a cast wheel, made of a single piece of metal, the crack would have continued travelling until it ran out of metal, which is could be the rim. Ie the whole wheel can break in two, where a spoked wheel, is more likely to stay attached and just go out of shape... a lot out of shape, but, not fail quite so catastrophically.
So, a spoked wheel tends to be more durable, and serviceable, provided they don't get completely mangled, made of individual components, hub, spokes and rim, its possible to re-true a wire laced wheel... or merely replace damaged 'bits' rather than the whole thing.
And on dirt, where the surface is as likely to move under the wheel, as the wheel is over the surface, you don't need or necessarily want the 'precision' you do on a race or road bike to 'hold' a line, from the wheel being more rigid not flexing and staying 'true' under the high loadings a road or race wheel is likely to be subject to, that a dirt bike, on dirt wont.
So, for a dirt-bike, its a more 'appropriate' wheel construction, and within the operating 'limits', offers a lot of advantages over a cast wheel that would beg more compromises; it would have to be less durable, have a shorter service life, be heavier and or more expansive.
In overall optimisation of design compromises, for a dirt-bike they still represent the best bet.
Forty years ago on tarmac? Cast wheels started to make an appearance. The bikes were getting more powerful; push-rod singles and twins that rarely made much more than 30-40bhp were getting bigger, heavier and more powerful, with 'fours' appearing on the scene, lifting both power and weight of bikes by almost half as much again, both, with higher speeds significantly increasing the load on wheels. Wire-spokes though still remained the 'norm' for a long while in the smaller displacement classes on lighter, less powerful machines.
However, early cast wheels were prone to cracking; and to make them strong enough, were often heavier than wire spoke wheels. If I recall correctly, Kawasaki were the first to offer cast spoke wheels on a production bike, and an American magazine actually weighed them pointing out how much heavier they were than the were wheels on the model the bike replaced (One of the early Z900's I think), and then offered lots of assurances to allay customer fears that despite the brochure saying that they were inspired by the 'endurance racer' wheels they shouldn't break like they did! Suzuki ran back into the problem with the early slab-side GSXR's, almost a decade later, when cast wheels had become far more accepted, having slimmed down the sections to help save weight, they were shown in proddy racing to flex and some I believe actually cracked, before they went to the much thicker section 'hollow-spoke' wheels used on the sling-shot models, I think.
Main reason for putting cast wheels on road bikes at that time, was purely economic; a cast wheel can be made in one shot, ad apart from a small increase in material cost, is barely any more expensive to make than a wheel hub, for a wire laced wheel, that the begs a more intricate steel pressed rim, or aluminium extrusion to be formed and welded, and then laboriously assembled, by hand, with perhaps 30 spokes per wheel, each cut from wire, threaded one end and 'formed' into a hook the other... best spokes BTW are not just bent bits of wire, they are 'hot forged' so as to avoid stress the metal at the bend.
It was a pure 'value engineering' exercise, it took manufacture cost out of the product, and added value in the ales brochure as a 'racing feature', increasing product profitability on both sides of the equation.
Honda! Avoided the issue for a long time; they used a 'composite' wheel construction.
Americans have bee making alloy car wheels by a process known as 'spinning'... its a cold forming method, a bit like extrusion, but rather than pushing the soft alloy through a shaped hole, you stick a billet into a lathe and then 'push' it into shape with a tyre lever as it 'spins'. This is how they made the distinctive 'Centreline' dragster wheels in the 60's & 70's... Incidentally, I actually have a 1950's book for how to build a 'school-boy racing go-kart' from a Villiers engined lawn mower, that gives schematic diagrams for how to make 6" Go-Kart wheels on a school lathe, this way!
However, the same technique was used to make 'Astralites' for motorbikes; a flanged rim was formed by cold 'spinning', a hub was cast, and aluminium spoke-plates, were riveted to either side, sandwiching the hub and rim between them to form the wheel.
The hub 'hung' on the spoke plates, in tension, like a wire spoke, but more rigidly attached via cross bolt or rivit, the plate could also take load in compression, making for a very light and very strong wheel that was more rigid than a wire laced wheel, but not as inflexible as a cast one, so had some compliance against fatigue fracture.
Honda adopted the construction and gave t the brand-name 'Com-Star', introduced quite early in the mid 70's I recall, they retained it right up until the 90's. Also of note, they were the first to make and use a carbon fibre wheel in GP Racing, as early as 1979 ISTR, on the NR500 oval-piston four-stroke, and possibly some of the same era NS500 triples. And they adopted the Com-Star modular construction for it, using. A lot of them broke, from the reports I have read!
More expensive to make than a simple cast wheel, its still less intensive than a wire laced wheel, but offers 'some' of the benefits of either.
Brings us up into the 90's, when large hollow section, thin-wall cast wheels, became the norm for sports-bikes, offering a very large amount of rigidity from pure 'section', weight saving from using the least metal in that section via the 'thin wall', and improved casting techniques, allowing the use of softer, more ductile grade aluminium, and material quality control that avoided so many 'inclusions' or 'reciprocity' which would make a wheel more prone to fatigue fracture, allowing cast wheels to be made cheaply and reliably, and actually e both stronger and lighter than alternatives....
And we saw the rid of the 'Paris Dakar' Replica, that spawned the big-bore 'Adventure-sport' bikes that saw wire laced wheels, again start being fitted to road bikes over 800cc..... and twins, now SERIOUSELY heavier and more powerful than those of old...
And these have me stumped.... loadings these bike could put on their wheels would beg a cast one and as few get the serious sort of off-road pounding a competition dirt bike would suffer, despite the atrocious state of a lot of British roads these days.... I have to consider that the added complexity and cost of making a wire-laced wheel for these things, more making one even stronger than they weren't way-back-when on lighter, less powerful road bikes, mean its probably a rather expensive bit of 'vanity' without any great sound engineering 'logic' behind it... other than, customer expect them to have wire-laced wheels to meet their expectations of the features a 'Dirt-Bike' ought to have, they are prepared to pay the 'premium' for them, and wouldn't buy them with anything else...
Interestingly, both BMW and Moto-Guzzi amongst other's to my recollection, have offered pseudo 'big-dirt' bikes with cast wheel.
Curiously, I don't recall any-one using the 'half way' compromise 'composite' construction wheels, that might make some more sense i this situation, on one.
SO, there you go, that's what's 'good' about a spoked wheel.. and a bit, OK a lot, more, and even more and probably equally unnecessary history about them... but what the heck... gives the knockers another chance to add to the band width offering even less relevant, 'TLDR' posts to the thread.
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...WHO the HELL let Tef out of his cage? 
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kawashima
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| Posted: 04:48 - 17 Jan 2016 Post subject: |
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| Polarbear wrote: | Triumph put spoked wheels onto a rim that takes tubeless tyres on their 'off road' versions of bike.
As far as I understand it, nowadays it is either looks, on an Enfield/WR, or practicability on an off road. A spoked wheel with a good stainless rim will take way more abuse than a mag wheel. Spokes flex and don't break, as do the stainless rims.
|
Thanks Plarbear, if they can have tubless tyres it makes sense why they have spoked ones for me.
| Teflon-Mike wrote: | A wire spoked wheel holds the rim in 'tension' on the spokes, which is very efficient use of metal, as the 'load' is trying to stretch it, and it will have to stretch a lot before it will snap.
In compression, a 'member' under load will try and bend to comply with the applied force, so it has to resist both compressive forces and bending forces, so to carry the same load force a spoke in compression, will tend to have to have a thicker 'section' to resist bending.
In theory, this means that 'within certain limits', its possible to make a spoked wheel that is lighter and or stronger than a cast one.
In practice, you can make a cast wheel that's lighter and stronger than a wire-spoked one....
I had to shift some old TZ wheels the Thursday, one pair were original alloy rimmed wire-spokes, the other were an awful lot stronger and lighter die-cast magnesium.... Original Swindon Dymags actually, which they were going back to for refurbishment and crack analysis, hinting at an issue with them... main one though, that whilst a lot lighter, and stronger, they are also a lot more expensive, and less durable. As said, the Dymags are prone to 'fatigue' cracking.
I was actually shifting them to get at another wheel, this one for my old Montesa trials bike.. that DID have a fatigue fractured hub! Fucker went on me on the last but one section of an event a few years back, on an obstacle on a steep climb! NOT NICE! But, being retrieved to see if the hub can be salvaged.. which s probably another story.
On a race track.. wheels tend to support much higher 'peak' loadings, certainly on modern bikes with the grip their tyres offer and the torque being out on them from 100+bhp engines, but on a dirt bike, you don't often get much with much over 50bhp, and tyres don't have anywhere near the grip on loose dirt as delugrip tarmac, so they will rarely generate anywhere near the same levels of loading, so the wheel need not be as rigid to support it...
On dirt, though, while the 'peak' loadings might not be as high, 'cyclic' loading, how often load is put on a and take off and put back on again, is likely to be greater, as the wheel takes a 'pounding' on every bump and jump, this is more likely to cause a 'fatigue' fracture on a cast wheel, making them less durable.
In trials, I run around 3psi pressure in the back tyre, its almost 'flat' before I launch it off an obstacle, so that the rim is taking almost all the landing force directly with little or no 'cushioning' from the tyre... I had a pair of tubless tyres on it at one pt that have slightly stiffer carcasses and can be run at zero pressure.
Again, the peak loading might not be particularly high, but the rim taking the full impact almost directly, the 'shock' load can be pretty severe. Here the lack of rigidity can offer some 'compliance' that a cast wheel holding the rim in compression, rather than tension lacks, again helping reduce fatigue stresses.
Its also more likely to result in a 'catastrophic failure'... when the hub 'went' on my trials bike wheel, the crack started at one of the sprocket bosses travelled through the hub, and stopped at one of the spoke eyes... there that bit of metal stopped.. had it been a cast wheel, made of a single piece of metal, the crack would have continued travelling until it ran out of metal, which is could be the rim. Ie the whole wheel can break in two, where a spoked wheel, is more likely to stay attached and just go out of shape... a lot out of shape, but, not fail quite so catastrophically.
So, a spoked wheel tends to be more durable, and serviceable, provided they don't get completely mangled, made of individual components, hub, spokes and rim, its possible to re-true a wire laced wheel... or merely replace damaged 'bits' rather than the whole thing.
And on dirt, where the surface is as likely to move under the wheel, as the wheel is over the surface, you don't need or necessarily want the 'precision' you do on a race or road bike to 'hold' a line, from the wheel being more rigid not flexing and staying 'true' under the high loadings a road or race wheel is likely to be subject to, that a dirt bike, on dirt wont.
So, for a dirt-bike, its a more 'appropriate' wheel construction, and within the operating 'limits', offers a lot of advantages over a cast wheel that would beg more compromises; it would have to be less durable, have a shorter service life, be heavier and or more expansive.
In overall optimisation of design compromises, for a dirt-bike they still represent the best bet.
Forty years ago on tarmac? Cast wheels started to make an appearance. The bikes were getting more powerful; push-rod singles and twins that rarely made much more than 30-40bhp were getting bigger, heavier and more powerful, with 'fours' appearing on the scene, lifting both power and weight of bikes by almost half as much again, both, with higher speeds significantly increasing the load on wheels. Wire-spokes though still remained the 'norm' for a long while in the smaller displacement classes on lighter, less powerful machines.
However, early cast wheels were prone to cracking; and to make them strong enough, were often heavier than wire spoke wheels. If I recall correctly, Kawasaki were the first to offer cast spoke wheels on a production bike, and an American magazine actually weighed them pointing out how much heavier they were than the were wheels on the model the bike replaced (One of the early Z900's I think), and then offered lots of assurances to allay customer fears that despite the brochure saying that they were inspired by the 'endurance racer' wheels they shouldn't break like they did! Suzuki ran back into the problem with the early slab-side GSXR's, almost a decade later, when cast wheels had become far more accepted, having slimmed down the sections to help save weight, they were shown in proddy racing to flex and some I believe actually cracked, before they went to the much thicker section 'hollow-spoke' wheels used on the sling-shot models, I think.
Main reason for putting cast wheels on road bikes at that time, was purely economic; a cast wheel can be made in one shot, ad apart from a small increase in material cost, is barely any more expensive to make than a wheel hub, for a wire laced wheel, that the begs a more intricate steel pressed rim, or aluminium extrusion to be formed and welded, and then laboriously assembled, by hand, with perhaps 30 spokes per wheel, each cut from wire, threaded one end and 'formed' into a hook the other... best spokes BTW are not just bent bits of wire, they are 'hot forged' so as to avoid stress the metal at the bend.
It was a pure 'value engineering' exercise, it took manufacture cost out of the product, and added value in the ales brochure as a 'racing feature', increasing product profitability on both sides of the equation.
Honda! Avoided the issue for a long time; they used a 'composite' wheel construction.
Americans have bee making alloy car wheels by a process known as 'spinning'... its a cold forming method, a bit like extrusion, but rather than pushing the soft alloy through a shaped hole, you stick a billet into a lathe and then 'push' it into shape with a tyre lever as it 'spins'. This is how they made the distinctive 'Centreline' dragster wheels in the 60's & 70's... Incidentally, I actually have a 1950's book for how to build a 'school-boy racing go-kart' from a Villiers engined lawn mower, that gives schematic diagrams for how to make 6" Go-Kart wheels on a school lathe, this way!
However, the same technique was used to make 'Astralites' for motorbikes; a flanged rim was formed by cold 'spinning', a hub was cast, and aluminium spoke-plates, were riveted to either side, sandwiching the hub and rim between them to form the wheel.
The hub 'hung' on the spoke plates, in tension, like a wire spoke, but more rigidly attached via cross bolt or rivit, the plate could also take load in compression, making for a very light and very strong wheel that was more rigid than a wire laced wheel, but not as inflexible as a cast one, so had some compliance against fatigue fracture.
Honda adopted the construction and gave t the brand-name 'Com-Star', introduced quite early in the mid 70's I recall, they retained it right up until the 90's. Also of note, they were the first to make and use a carbon fibre wheel in GP Racing, as early as 1979 ISTR, on the NR500 oval-piston four-stroke, and possibly some of the same era NS500 triples. And they adopted the Com-Star modular construction for it, using. A lot of them broke, from the reports I have read!
More expensive to make than a simple cast wheel, its still less intensive than a wire laced wheel, but offers 'some' of the benefits of either.
Brings us up into the 90's, when large hollow section, thin-wall cast wheels, became the norm for sports-bikes, offering a very large amount of rigidity from pure 'section', weight saving from using the least metal in that section via the 'thin wall', and improved casting techniques, allowing the use of softer, more ductile grade aluminium, and material quality control that avoided so many 'inclusions' or 'reciprocity' which would make a wheel more prone to fatigue fracture, allowing cast wheels to be made cheaply and reliably, and actually e both stronger and lighter than alternatives....
And we saw the rid of the 'Paris Dakar' Replica, that spawned the big-bore 'Adventure-sport' bikes that saw wire laced wheels, again start being fitted to road bikes over 800cc..... and twins, now SERIOUSELY heavier and more powerful than those of old...
And these have me stumped.... loadings these bike could put on their wheels would beg a cast one and as few get the serious sort of off-road pounding a competition dirt bike would suffer, despite the atrocious state of a lot of British roads these days.... I have to consider that the added complexity and cost of making a wire-laced wheel for these things, more making one even stronger than they weren't way-back-when on lighter, less powerful road bikes, mean its probably a rather expensive bit of 'vanity' without any great sound engineering 'logic' behind it... other than, customer expect them to have wire-laced wheels to meet their expectations of the features a 'Dirt-Bike' ought to have, they are prepared to pay the 'premium' for them, and wouldn't buy them with anything else...
Interestingly, both BMW and Moto-Guzzi amongst other's to my recollection, have offered pseudo 'big-dirt' bikes with cast wheel.
Curiously, I don't recall any-one using the 'half way' compromise 'composite' construction wheels, that might make some more sense i this situation, on one.
SO, there you go, that's what's 'good' about a spoked wheel.. and a bit, OK a lot, more, and even more and probably equally unnecessary history about them... but what the heck... gives the knockers another chance to add to the band width offering even less relevant, 'TLDR' posts to the thread. |
Thanks Teflon-Mike! It was very interesting for me!
On and Off different type of load and move to tyre and wheels.
And how they overcome the load they receive. very differently.
Cast breaks more significantly once start to break than spoked one.
Especially viewpoint of manufacturing cost was interesting!
I remembered honda com-star weird looking wheels. Doesn't look better than both normal spoked or cast if they broke so.
Recent heavy adventure bikes having spoked wheels. They must suffer a lot of stress if used heavily. They must be expensive.
Overall I was thinking cast wheels were invincible if used on-road, but not that true, after reading your post.
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| Teflon-Mike |
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Teflon-Mike
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Posted: 16:53 - 17 Jan 2016  Post subject: |
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| kawashima wrote: | Thanks Teflon-Mike! It was very interesting for me! |
Your're welcome.
| kawashima wrote: | I remembered honda com-star weird looking wheels. Doesn't look better than both normal spoked or cast if they broke so. |
The Honda Com-Starts were pretty darn durable, on the whole. Remark about 'them' breaking, was in reference to Hondas experiments in Carbon fibre.
Without going and digging out the academic 'technical paper' on the topic, I photo-copied when I was at uni, umpety decade ago, OTMH, they made the Carbon Fibre spoke plates from carbon cloth, pressed over a former and cured in an auto-clave. THEN with formed plates, just like an aluminium 'blank'they 'pressed' holes in either end to bolt them to the hub and rim.
But, chopping the fibres when they pierced the hole, and no 'stress relief' in the formed material around the hole, they had inadvertently created a stress raiser AND in the 'frayed' ends of the fibres that were cut, pre-made crack initiation sites.
I service subject to stress, then, the bolts could 'fret' the holes making them even weaker, and the a crack would 'run' fro the hole through the spoke, so the wheel 'broke up'.
Whole paper as devoted to the problem and how they attempted to solve it. Seem to recall, that after they identified it, they tried piercing the holes in the cloth before it was cured into 'hard' CF. They tried layering up the area around the whole to strengthen it, and numerous other things. Think the final 'fix' was to form the spoke plates around pre-made 'bosses', which I seem to recall were straight graphite carbon...
Tangentially to topic; but when I was ten, in 1980 a British Film, made with American money, starring British pop star David Essex and american actor, Beau Bridges... called 'Silver-Dream-Racer' was released... VERY VERY cheesy, if you want to watch it, but absolutely FASCINATING!
Bridges plays a loud-mouth Yank bike racer, loosely modelled on I believe, Randy Mamola and Eddie Lawson, represent the American 'Invasion' of European dominated GP road-racing, of the era, bringing with them big-bugs sponsors and dirt-track rear wheel steering and lots of 'attitude'.. and if anything the Bridges character, as over the top as he played it, is probably some-what more restrained than characters he was based on! Anyway, track rival is 'under-dog' British 'clubman' played by David Essex, a store-man and petrol pump attendant in a London car workshop, who for some curious reason seem to have a lot of left hand drive Pontiac's (Not sold in the UK!) in to have their oil changed!
Anyway, Nick Freeman (Essex) is struggling to make ends meet and pay his race entries, nursing an old air-cooled Suzuki GT500 twin, stripped for racing, along on over sized piston rings, cornflake packet gaskets and gaffer tape, to usually break down before he can win. Bruce McBride (Bridges) Has all the best tackle, (water-cooled, RG500 square four, I think), two team mates to run interference and stop any-one getting past him in a race, a team of work mechanics to prep the bike, with an articulated lorry load of work-shop equipment, and a motor-home for him to relax in before and after a race where Brit Nick just got a Transit van!
BUT.. Nicks Brother, is an aero-space engineer, and has been building a bike to beat the world in his shed for the last five years... when he comes off a dirt-bike in a quarry and gets himself killed, and his widow, who is best remembered as the Nescafe advert woman (Diane Kiene, I think) Gives Nick the 'Silver-Dream-Racer'.. which is 'almost' finished.. and is water cooled and ha disc valves and the 'secret weapon' - a carbon-fibre frame... a bike, to level the playing field, and let Nick stick it to the loud-mouth Yank on the track.....
Preposterous.. a complete no-body, in their back garden, building motorbike out of a 'then' unheard of 'space age' material.... yeah RIGHT!
You have to remember that this was 1980.... pre-ates Kiwi John Britain dong it for real at Daytona, by almost a decade... BUT the daft thing was, there was actually far more 'fact' in the film than there was 'fiction'... and as a student I wanted to know how much!
Incredibly, the 'Silver-Dream-Racer' actually WAS made from real carbon fibre! Or at least one of the three they built for the film was.
Used a conventional tube frame construction, the actual tubes formed from mandrel winding actual filament Carbon onto a former,, and laid-up with resin, much like conventional GRP, rather than 'pre-impregnated' sheet as ha become the more usual means of laying up C-F. Technique had, ISTR been pioneers to make a carbon-fibre push bike, by Peugot, and later adopted by Honda to make Carbo-Fibre fork-stanchions, which was the topic of a whole other research paper, looking at how they achieved that!
In the film Bruce McBride, the Loud-Mouth Yank, rode for Suzuki, and probably small co-incidence that thier team livery was nie on indistinguishable fro that of UK Based Heron Suzuki.. BUT, at that time, Heron Suzuki were building their own frames around the 'production' RG500 square-four engines, and while they hadn't got a Carbon-Fibre frame... they had made one!
Heron had an ex F1 car construction engineer, who was experimenting with making 'monochoc' or box section motorbike 'chassis' out of turkey wrap... OK, well incredibly thin aluminium 'foil', glued together and the pulled apart to form a 'honey-comb' section a bit like corrugated card-board! Used n the Aerospace industry, stuff is incredibly 'light' and when used in thick carefully orientated 'sections' in compression, astoundingly 'strong'.
'Honey-comb' could also be formed from sheet Carbon-Fibre, and be even stronger and even lighter than aluminium, and either 'core' material could be 'skinned' in either CF or turkey-foil to make the final structure.
Heron, apparently experimented with all four possible permutations, but settled on aluminium over aluminium for their race bikes, as it was more resilient to fatigue, and more practical for making track-side repairs or modifications.
Their sister team Galini Suzuki in Italy, adopted the construction and went further, making I think it was five frames, all skinned in carbon, at least one over a carbon honey-comb, the other over aluminium.... but, it never raced! Suzuki Japan, pulled the 'plug' o the 'franchise' European importers, and created thier own local operating businesses, and fro accounts I read, Suzuki 'people' turned up at both Heron in Britain and Gallini in italy, and gang-handed loaded up all Suzuki 'owned' parts, tools and equipment into a van and carted it off, leaving both teams with no engines.. or tools!
The UK team, was I believe later incorporated into the Suzuki 'factory' GP department, during the Kevin Swantz era, but the honey-comb frames wee ever seen again. apparently, Suzuki deemed them irrelevant to 'production' motorcycles, and wanted to further 'conventional' frame construction development within the GP effort....
Poor Kevin! Because they NEVER made a GP bike that 'handled' again, and he got the pins in his bones to prove it! Mind you.... probably just as well, as a shit-or-bust Yakie 'loud-mouth' he would probably still have crashed them... and I would't have been able to have turkey for Christmas... bastards.. I hate turkey. almost a much as I loath brussel sprouts!
Anyway... wasn't the end of the REAL 'Silver-Dream-Racer'.
Engineer responsible for the Heron Honey-comb frames, I believe was take on board by 'Armstrong'.. ow THIS is a flukey bit of history!
Armstrong-Sidley, were a TINY division of the Sidley 'armaments' corporation, more commonly associated with the Hawker-Sidley-Harrier 'Jump-Jet' aeroplane. In 1972, the mighty BSA group went bankrupt', and like Sidley, had a large umber of government armaments contracts. Sidley bought chuk of the BSA group off the official receiver, and Armstrong, who built scout-car I think, might even have been one of them. However, amongst the contract was one to make and support the BSA B40 motorcycles used by the army... small problem.. they didn't make motorbikes! Slightly bigger problem... they couldn't make motorbikes! The receiver had sold a whole chunk of the BSA B40 tooling and 'spars' to a cap called Alan Clews, a notable Scramble rider, and 'special-builder' who wrapped Cheney scrambles frames around tuned up B40 engines....
So, Sidley bought him out! Creating the Armstrong Motorcycle company. Later to become CCM or 'Clews Competition Motorcycles'.... this also spawned the Armtrong-Bombardier-Rotax military motorcycle, often seen sporting Harley Davidson badges, from an experment by Clews to stuff an overhead cam Rotax engine into a Cheney scrambles frame......
Slightly more successful, but probably less profitable, they got their hands on this hap from Heron, AND some disc valved tandem two-stroke engines from Rotax, and went road-racing.... with ISTR Kenny Irons and Mick Ward? in UK 240 & 350cc GP championships, giving a 'guest' ride to Neil McKenzie, ironically later Swantzs's team mate with a work ride at Suzuki! Oh! The wheels within wheels of the TINY world of motorcycles!
I think the Armstrong, had about three successful seasons in the UK, but never got the funding to contend the world-championship, while Sidley, seemed to want desperately to get 'out' of the bike business, selling CCM back to Alen Clews in the end, and selling their take in the Bombardier-Armtrong-Rotax out to Bombardier, I believe.
The Armstrong Carbo-Fibre frame, then became the 'kit' Hijera, I thik, usually lugged to take a Rotax or Yamaha big four-stroke single for Sound-of-singles racing... I recall they sold a lot of kits to Japan....
MEANWHILE... more wheels in the wheel! Gllini! Left without an egine, and all set to go racing.... were adopted by the Castiglioni brother, then owners of Cagiva.... AND while they had no engine... they DID have a pair of crank-cases.. loaned by Suzuki before they pulled the plug to establish the mounting pots for the frame.... and conveniently not ni the work-shop when Suzuki claared it out, beg out at a subcontractor being measured and fitted for 'dies' to make the engine cradle to take them... These became the basis of the Cagiva FP bike, raced by Randy Mamola, and later Ron Haslam....
https://scontent-lhr3-1.xx.fbcdn.net/hphotos-xft1/v/t1.0-9/1005661_638259756198945_1948677317_n.jpg?oh=60a31c5d64ff00cc8a1acc7c698ea6f1&oe=57013C6A
There you go, that's Randy... pretty chtty pic, blown up fro an old film-photoI took at the British GP in 1990...
Ah! But the Heron & Gallini bikes were RG500 square-fours! The Mamola-Cagva was a V-four! Correct! Ad Heron & Gllini had been working on frames to house the 'last' of the square fours, when Suzuki announced the V4, they would pt into the Swantz bike, and between that and the plug being pulled, Gallini had been sent advance V4 crank cases.. and from those, Cagiva 'reverse engineers' the Suzuki V4 engine and built their own based on it.
SO!!! Back to the Silver-Dream-Racer! It was 'all going on, and Carbon-Fibre race bikes were being built, in maybe not garden shed, but certainly in small engineering work-shops by dedicted 'Shedologists'!
Ah, yeah, BUT! One thing to get your hands on some fancy new material and make a bike not of it in your back garden! But to scratch build an 'advanced' racing engine in your garage?
Curiously less well documented, but astoundingly more common, actually.
Probably the best documented is the Grieves. In the 1950's Bert grieves was a dedicated Shedologist, and fan of the Villiers two-stroke engine. He built his own 'trials' and 'scrambles' socials around these, essentially 'lawn-mower' engines! Eventually stepping up to become a small scale motorcycle manufacturer, having evolved the Villiers lawn-mower otor into a rather 'potent' competition power-plant, not just for trials and scrambles, but road-racing too, with the 350c Greeves, Silverstone.
Cotton, had a similar history, evolving proprietary two-stroke 'lawn mower' engines into potent competition motorcycles, as did DOT. And famouse name from Trials, Birmingham boy, Vale Onslow, actually rode his legendary 'Val-On' Special from Birmigham to London to collect his, I think OBE.
Simplicity of the two-stroke engine, in the 1950' & 60's and to the 70's made it incredibly 'adptable' and easy for some-one with a bit of enthusiasm, to take a simple piston ported lawn-mower engine and start tinkering to make it a bit more 'peppy'. Not a very bg leap from that to welding crank-cases together to make a tandem twin two-stroke or even a square four, though more likely to start by boring holes in the crank-cases to add reed or disc valves.
One completely scratch-built 'racer' I found reference to fro the 'Silver-Dream-Racer' er, did't have a carbon frame, but it did have an entirely shed-built tandem twin engine, loosely based on the same rotax engine as used the Armstrong, but re-engineered to incorporate 'double-disc' valves.. one on either side of the crank, to double the area the crank-case cold suck in charge through..... don't think it was very successful, mainly due to the chaps that made it, two brothers and their Dad, ISTR... I think they kept running out of money or something....
However... plot of the film, as fantastic as it was, was actually less incredible than a lot of what was actually happening, in reality, garden sheds and little workshops, presumably not just n the UK, but, wherever shedologists have a spanner and a motorbike and a 'stupid' idea!
And NOWHERE, would seem to fit that description better than New-Zealand! With a vibrant history of eccentric shedologists, doing silly things like making double-overhead camshaft cylinder heads for 1920's Indian scouts, and taking them to Utah!
So, that was my quest, digging through the academic archives, in the Materials Technology section of the Uni Library, looking for references to Carbon-Fibre used in motorcycle construction.
The most remarkeable thing i that though, was Honda. And how early they were messing with the stuff, and how much they were trying to make out of the stuff.. which brings us back to the 'wheels'.... eventually.....
The quite bizarre thing about Honda was, having seemingly leaped at this new 'technology' was how utterly 'conventional' they were n how they tried to utilise it.
The Carbon-Fibre wheels, case in point. Honda looked at the wheels they already made, and simply tried a direct 'material substitution' making the exact same components, in the exact same shape, and bolting them together in the same way, 'just' made out of the alternative material, rather than looking at the thing they wanted to make, and designing the 'whole' artefact, its form and its construction to suit the material....
The wound filament forks, anther example. They looked at a conventional pair of tubular telescopic motorcycle forks... and copied the exact same shape in carbon fibre....
At the time, there were even more folk experimenting with 'funny front ends' on motorcycles, alternatives to the telescopic fork, notably in England a devoted Shedologist, Roy Creacy, father of the 'flyng banana' a bizarre motorcycle with a roof, sort of a Robin Relient 3-wheeler (whose engine it used!) missig aother wheel ad its doors! But with an ovatve 'Hub-Centre-steer' front suspension system,, bit like a Bmota Tesi.... There was also the Hossak, that inspired BMW's production Funny-Front end 'Tele-Lever', amogst many others... Yamaha's GTS was inspired by an american shedologist in the same vein.
But HONDA! At that time, were backing the only 'funy-front-end' bike in GP racing I ever recall, the 'Elf', that used a single sided 'swing-arm' front suspension a bit like the Yamaha GTS 20 years later.
To make a front suspension system out of Carbo-Fibre, then, it would have been far more logical, to look at the material and the sort of 'sections' it could best be formed into to gain the greatest advantage from its incredibly stiffness, and see a 'tube' didn't utilise it very well! A box section DID.. so WHY not make a box section swig arm, and use an 'elf' type swig arm front suspension system, WHY try copy a telescopic-fork that most thought was rather 'compromised' to start with!
Strange, strange corporate thinking. So ready to embrace the 'new' yet so reluctant to let go of the 'old'...
BUT, by curious 'dint' of Eddisoia rasoning, like Edison not 'failing' to invent an electric light-bulb in 9,999 experiments, but 'discovering' 9,999 ways NOT to make an electric lght-bulb, before the one experiment cracked it.... Hondas early experiments in Carbon-Fibre, trying so many different ways, to exploit the material, and make it work, probably did the most to help find where carbon-fibre couldn't be readily exploited and push it into places it could.
Those broken Carbo-Fibre Com-Stars, weren't, by Edisonian logic, 'Failures' they proved may ways how NOT to build a carbon fibre wheel!
There you go, another muse for'em to pot memes on!
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ScaredyCat
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Posted: 17:07 - 17 Jan 2016  Post subject: |
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| Teflon-Mike wrote: | | kawashima wrote: | Thanks Teflon-Mike! It was very interesting for me! |
Your're welcome.
| kawashima wrote: | I remembered honda com-star weird looking wheels. Doesn't look better than both normal spoked or cast if they broke so. |
The Honda Com-Starts were pretty darn durable, on the whole. Remark about 'them' breaking, was in reference to Hondas experiments in Carbon fibre.
Without going and digging out the academic 'technical paper' on the topic, I photo-copied when I was at uni, umpety decade ago, OTMH, they made the Carbon Fibre spoke plates from carbon cloth, pressed over a former and cured in an auto-clave. THEN with formed plates, just like an aluminium 'blank'they 'pressed' holes in either end to bolt them to the hub and rim.
But, chopping the fibres when they pierced the hole, and no 'stress relief' in the formed material around the hole, they had inadvertently created a stress raiser AND in the 'frayed' ends of the fibres that were cut, pre-made crack initiation sites.
I service subject to stress, then, the bolts could 'fret' the holes making them even weaker, and the a crack would 'run' fro the hole through the spoke, so the wheel 'broke up'.
Whole paper as devoted to the problem and how they attempted to solve it. Seem to recall, that after they identified it, they tried piercing the holes in the cloth before it was cured into 'hard' CF. They tried layering up the area around the whole to strengthen it, and numerous other things. Think the final 'fix' was to form the spoke plates around pre-made 'bosses', which I seem to recall were straight graphite carbon...
Tangentially to topic; but when I was ten, in 1980 a British Film, made with American money, starring British pop star David Essex and american actor, Beau Bridges... called 'Silver-Dream-Racer' was released... VERY VERY cheesy, if you want to watch it, but absolutely FASCINATING!
Bridges plays a loud-mouth Yank bike racer, loosely modelled on I believe, Randy Mamola and Eddie Lawson, represent the American 'Invasion' of European dominated GP road-racing, of the era, bringing with them big-bugs sponsors and dirt-track rear wheel steering and lots of 'attitude'.. and if anything the Bridges character, as over the top as he played it, is probably some-what more restrained than characters he was based on! Anyway, track rival is 'under-dog' British 'clubman' played by David Essex, a store-man and petrol pump attendant in a London car workshop, who for some curious reason seem to have a lot of left hand drive Pontiac's (Not sold in the UK!) in to have their oil changed!
Anyway, Nick Freeman (Essex) is struggling to make ends meet and pay his race entries, nursing an old air-cooled Suzuki GT500 twin, stripped for racing, along on over sized piston rings, cornflake packet gaskets and gaffer tape, to usually break down before he can win. Bruce McBride (Bridges) Has all the best tackle, (water-cooled, RG500 square four, I think), two team mates to run interference and stop any-one getting past him in a race, a team of work mechanics to prep the bike, with an articulated lorry load of work-shop equipment, and a motor-home for him to relax in before and after a race where Brit Nick just got a Transit van!
BUT.. Nicks Brother, is an aero-space engineer, and has been building a bike to beat the world in his shed for the last five years... when he comes off a dirt-bike in a quarry and gets himself killed, and his widow, who is best remembered as the Nescafe advert woman (Diane Kiene, I think) Gives Nick the 'Silver-Dream-Racer'.. which is 'almost' finished.. and is water cooled and ha disc valves and the 'secret weapon' - a carbon-fibre frame... a bike, to level the playing field, and let Nick stick it to the loud-mouth Yank on the track.....
Preposterous.. a complete no-body, in their back garden, building motorbike out of a 'then' unheard of 'space age' material.... yeah RIGHT!
You have to remember that this was 1980.... pre-ates Kiwi John Britain dong it for real at Daytona, by almost a decade... BUT the daft thing was, there was actually far more 'fact' in the film than there was 'fiction'... and as a student I wanted to know how much!
Incredibly, the 'Silver-Dream-Racer' actually WAS made from real carbon fibre! Or at least one of the three they built for the film was.
Used a conventional tube frame construction, the actual tubes formed from mandrel winding actual filament Carbon onto a former,, and laid-up with resin, much like conventional GRP, rather than 'pre-impregnated' sheet as ha become the more usual means of laying up C-F. Technique had, ISTR been pioneers to make a carbon-fibre push bike, by Peugot, and later adopted by Honda to make Carbo-Fibre fork-stanchions, which was the topic of a whole other research paper, looking at how they achieved that!
In the film Bruce McBride, the Loud-Mouth Yank, rode for Suzuki, and probably small co-incidence that thier team livery was nie on indistinguishable fro that of UK Based Heron Suzuki.. BUT, at that time, Heron Suzuki were building their own frames around the 'production' RG500 square-four engines, and while they hadn't got a Carbon-Fibre frame... they had made one!
Heron had an ex F1 car construction engineer, who was experimenting with making 'monochoc' or box section motorbike 'chassis' out of turkey wrap... OK, well incredibly thin aluminium 'foil', glued together and the pulled apart to form a 'honey-comb' section a bit like corrugated card-board! Used n the Aerospace industry, stuff is incredibly 'light' and when used in thick carefully orientated 'sections' in compression, astoundingly 'strong'.
'Honey-comb' could also be formed from sheet Carbon-Fibre, and be even stronger and even lighter than aluminium, and either 'core' material could be 'skinned' in either CF or turkey-foil to make the final structure.
Heron, apparently experimented with all four possible permutations, but settled on aluminium over aluminium for their race bikes, as it was more resilient to fatigue, and more practical for making track-side repairs or modifications.
Their sister team Galini Suzuki in Italy, adopted the construction and went further, making I think it was five frames, all skinned in carbon, at least one over a carbon honey-comb, the other over aluminium.... but, it never raced! Suzuki Japan, pulled the 'plug' o the 'franchise' European importers, and created thier own local operating businesses, and fro accounts I read, Suzuki 'people' turned up at both Heron in Britain and Gallini in italy, and gang-handed loaded up all Suzuki 'owned' parts, tools and equipment into a van and carted it off, leaving both teams with no engines.. or tools!
The UK team, was I believe later incorporated into the Suzuki 'factory' GP department, during the Kevin Swantz era, but the honey-comb frames wee ever seen again. apparently, Suzuki deemed them irrelevant to 'production' motorcycles, and wanted to further 'conventional' frame construction development within the GP effort....
Poor Kevin! Because they NEVER made a GP bike that 'handled' again, and he got the pins in his bones to prove it! Mind you.... probably just as well, as a shit-or-bust Yakie 'loud-mouth' he would probably still have crashed them... and I would't have been able to have turkey for Christmas... bastards.. I hate turkey. almost a much as I loath brussel sprouts!
Anyway... wasn't the end of the REAL 'Silver-Dream-Racer'.
Engineer responsible for the Heron Honey-comb frames, I believe was take on board by 'Armstrong'.. ow THIS is a flukey bit of history!
Armstrong-Sidley, were a TINY division of the Sidley 'armaments' corporation, more commonly associated with the Hawker-Sidley-Harrier 'Jump-Jet' aeroplane. In 1972, the mighty BSA group went bankrupt', and like Sidley, had a large umber of government armaments contracts. Sidley bought chuk of the BSA group off the official receiver, and Armstrong, who built scout-car I think, might even have been one of them. However, amongst the contract was one to make and support the BSA B40 motorcycles used by the army... small problem.. they didn't make motorbikes! Slightly bigger problem... they couldn't make motorbikes! The receiver had sold a whole chunk of the BSA B40 tooling and 'spars' to a cap called Alan Clews, a notable Scramble rider, and 'special-builder' who wrapped Cheney scrambles frames around tuned up B40 engines....
So, Sidley bought him out! Creating the Armstrong Motorcycle company. Later to become CCM or 'Clews Competition Motorcycles'.... this also spawned the Armtrong-Bombardier-Rotax military motorcycle, often seen sporting Harley Davidson badges, from an experment by Clews to stuff an overhead cam Rotax engine into a Cheney scrambles frame......
Slightly more successful, but probably less profitable, they got their hands on this hap from Heron, AND some disc valved tandem two-stroke engines from Rotax, and went road-racing.... with ISTR Kenny Irons and Mick Ward? in UK 240 & 350cc GP championships, giving a 'guest' ride to Neil McKenzie, ironically later Swantzs's team mate with a work ride at Suzuki! Oh! The wheels within wheels of the TINY world of motorcycles!
I think the Armstrong, had about three successful seasons in the UK, but never got the funding to contend the world-championship, while Sidley, seemed to want desperately to get 'out' of the bike business, selling CCM back to Alen Clews in the end, and selling their take in the Bombardier-Armtrong-Rotax out to Bombardier, I believe.
The Armstrong Carbo-Fibre frame, then became the 'kit' Hijera, I thik, usually lugged to take a Rotax or Yamaha big four-stroke single for Sound-of-singles racing... I recall they sold a lot of kits to Japan....
MEANWHILE... more wheels in the wheel! Gllini! Left without an egine, and all set to go racing.... were adopted by the Castiglioni brother, then owners of Cagiva.... AND while they had no engine... they DID have a pair of crank-cases.. loaned by Suzuki before they pulled the plug to establish the mounting pots for the frame.... and conveniently not ni the work-shop when Suzuki claared it out, beg out at a subcontractor being measured and fitted for 'dies' to make the engine cradle to take them... These became the basis of the Cagiva FP bike, raced by Randy Mamola, and later Ron Haslam....
https://scontent-lhr3-1.xx.fbcdn.net/hphotos-xft1/v/t1.0-9/1005661_638259756198945_1948677317_n.jpg?oh=60a31c5d64ff00cc8a1acc7c698ea6f1&oe=57013C6A
There you go, that's Randy... pretty chtty pic, blown up fro an old film-photoI took at the British GP in 1990...
Ah! But the Heron & Gallini bikes were RG500 square-fours! The Mamola-Cagva was a V-four! Correct! Ad Heron & Gllini had been working on frames to house the 'last' of the square fours, when Suzuki announced the V4, they would pt into the Swantz bike, and between that and the plug being pulled, Gallini had been sent advance V4 crank cases.. and from those, Cagiva 'reverse engineers' the Suzuki V4 engine and built their own based on it.
SO!!! Back to the Silver-Dream-Racer! It was 'all going on, and Carbon-Fibre race bikes were being built, in maybe not garden shed, but certainly in small engineering work-shops by dedicted 'Shedologists'!
Ah, yeah, BUT! One thing to get your hands on some fancy new material and make a bike not of it in your back garden! But to scratch build an 'advanced' racing engine in your garage?
Curiously less well documented, but astoundingly more common, actually.
Probably the best documented is the Grieves. In the 1950's Bert grieves was a dedicated Shedologist, and fan of the Villiers two-stroke engine. He built his own 'trials' and 'scrambles' socials around these, essentially 'lawn-mower' engines! Eventually stepping up to become a small scale motorcycle manufacturer, having evolved the Villiers lawn-mower otor into a rather 'potent' competition power-plant, not just for trials and scrambles, but road-racing too, with the 350c Greeves, Silverstone.
Cotton, had a similar history, evolving proprietary two-stroke 'lawn mower' engines into potent competition motorcycles, as did DOT. And famouse name from Trials, Birmingham boy, Vale Onslow, actually rode his legendary 'Val-On' Special from Birmigham to London to collect his, I think OBE.
Simplicity of the two-stroke engine, in the 1950' & 60's and to the 70's made it incredibly 'adptable' and easy for some-one with a bit of enthusiasm, to take a simple piston ported lawn-mower engine and start tinkering to make it a bit more 'peppy'. Not a very bg leap from that to welding crank-cases together to make a tandem twin two-stroke or even a square four, though more likely to start by boring holes in the crank-cases to add reed or disc valves.
One completely scratch-built 'racer' I found reference to fro the 'Silver-Dream-Racer' er, did't have a carbon frame, but it did have an entirely shed-built tandem twin engine, loosely based on the same rotax engine as used the Armstrong, but re-engineered to incorporate 'double-disc' valves.. one on either side of the crank, to double the area the crank-case cold suck in charge through..... don't think it was very successful, mainly due to the chaps that made it, two brothers and their Dad, ISTR... I think they kept running out of money or something....
However... plot of the film, as fantastic as it was, was actually less incredible than a lot of what was actually happening, in reality, garden sheds and little workshops, presumably not just n the UK, but, wherever shedologists have a spanner and a motorbike and a 'stupid' idea!
And NOWHERE, would seem to fit that description better than New-Zealand! With a vibrant history of eccentric shedologists, doing silly things like making double-overhead camshaft cylinder heads for 1920's Indian scouts, and taking them to Utah!
So, that was my quest, digging through the academic archives, in the Materials Technology section of the Uni Library, looking for references to Carbon-Fibre used in motorcycle construction.
The most remarkeable thing i that though, was Honda. And how early they were messing with the stuff, and how much they were trying to make out of the stuff.. which brings us back to the 'wheels'.... eventually.....
The quite bizarre thing about Honda was, having seemingly leaped at this new 'technology' was how utterly 'conventional' they were n how they tried to utilise it.
The Carbon-Fibre wheels, case in point. Honda looked at the wheels they already made, and simply tried a direct 'material substitution' making the exact same components, in the exact same shape, and bolting them together in the same way, 'just' made out of the alternative material, rather than looking at the thing they wanted to make, and designing the 'whole' artefact, its form and its construction to suit the material....
The wound filament forks, anther example. They looked at a conventional pair of tubular telescopic motorcycle forks... and copied the exact same shape in carbon fibre....
At the time, there were even more folk experimenting with 'funny front ends' on motorcycles, alternatives to the telescopic fork, notably in England a devoted Shedologist, Roy Creacy, father of the 'flyng banana' a bizarre motorcycle with a roof, sort of a Robin Relient 3-wheeler (whose engine it used!) missig aother wheel ad its doors! But with an ovatve 'Hub-Centre-steer' front suspension system,, bit like a Bmota Tesi.... There was also the Hossak, that inspired BMW's production Funny-Front end 'Tele-Lever', amogst many others... Yamaha's GTS was inspired by an american shedologist in the same vein.
But HONDA! At that time, were backing the only 'funy-front-end' bike in GP racing I ever recall, the 'Elf', that used a single sided 'swing-arm' front suspension a bit like the Yamaha GTS 20 years later.
To make a front suspension system out of Carbo-Fibre, then, it would have been far more logical, to look at the material and the sort of 'sections' it could best be formed into to gain the greatest advantage from its incredibly stiffness, and see a 'tube' didn't utilise it very well! A box section DID.. so WHY not make a box section swig arm, and use an 'elf' type swig arm front suspension system, WHY try copy a telescopic-fork that most thought was rather 'compromised' to start with!
Strange, strange corporate thinking. So ready to embrace the 'new' yet so reluctant to let go of the 'old'...
BUT, by curious 'dint' of Eddisoia rasoning, like Edison not 'failing' to invent an electric light-bulb in 9,999 experiments, but 'discovering' 9,999 ways NOT to make an electric lght-bulb, before the one experiment cracked it.... Hondas early experiments in Carbon-Fibre, trying so many different ways, to exploit the material, and make it work, probably did the most to help find where carbon-fibre couldn't be readily exploited and push it into places it could.
Those broken Carbo-Fibre Com-Stars, weren't, by Edisonian logic, 'Failures' they proved may ways how NOT to build a carbon fibre wheel!
There you go, another muse for'em to pot memes on! |
Holy Fucking Shit...
I've heard that the BBC are turning that post into a 64 episode epic drama....
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Honda CBF125 ↳ Speed Triple |
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| trevor saxe-coburg-gotha |
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trevor saxe-coburg-gotha
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| Posted: 17:50 - 17 Jan 2016 Post subject: |
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Fwiw I definitely prefer the cast on the SR - but then, spoke on TDR. /shrug
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| Fizzer Thou |
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Fizzer Thou
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| Posted: 18:12 - 17 Jan 2016 Post subject: |
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This is the picture that came to mind when I read the OPs post
https://i666.photobucket.com/albums/vv23/WiNot_Rhencullen/Bikes/BikesBikesBikes192.jpg
The reports of very flexible cast wheels on the oil cooled Gixers like the GSXR1100H would be enough to make someone look for a stronger wheel,but that would make the bike heavier.But cast wheels like on the GS1000 were so heavy it did affect handling 
But the spoked wheels on several of my bikes are more difficult to maintain than the cast wheels on my other bikes 
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trevor saxe-coburg-gotha
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| deadwolf |
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deadwolf
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| Posted: 07:37 - 18 Jan 2016 Post subject: |
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| UncleFester |
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| woo |
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woo
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| Posted: 13:28 - 18 Jan 2016 Post subject: |
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mike you need to add a tl:dr column to your info
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Old Thread Alert!
The last post was made 10 years, 235 days ago. Instead of replying here, would creating a new thread be more useful? |
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