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Dr Alex Moulton died today at age 92. As well as being the progenitor of small wheeled bikes he had a big hand in the Issigonis Mini. He designed the 'rubber cone' suspension used pre/post the hydraulastic versions.
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Interesting chap. The obit gives the impression the bikes are historic - the later generation of space frame ones are still in production, but quite pricey.
www.moultonbicycles.co.uk/heritage.html
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>>an interest which would lead to a highly fruitful partnership with Sir Alec Issigonis, notably on Hydrolastic suspension systems for, among others, the Austin Mini. Hydrolastic evolved into the so-called Hydrogas system
That's not right, surely?
I've never had a Mini, but I thought they were all (bouncy) rubber, apart from a few years with hydrolastic.
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True, they started and ended on rubber lumps and trumpets, with a period on the Hydrolastic (I had a 1967 Hornet with that, changed the rotten rear subframe, threw the knackered hydrolastic bits away and put rubber lumps on)
The hydragas was on other BL cars.
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It's right that Hydrolastic became Hydrasag, I mean Hydragas.
It's also right that the Mini used Hydrolastic for some years.
And it's also true that the Mini did not use Hydragas.
I used to top up my Maxi's suspension with 50-50 water/antifreeze through a modified greasegun rather than take it to the garage when it needed a 'boost'.
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>>I used to top up my Maxi's suspension with 50-50 water/antifreeze through a modified greasegun rather than take it to the garage when it needed a 'boost'.
There must have been something wrong with it. My father and I between us ran an Austin 1800 for nearly 20 years. In all that time it only ever had its hydrolastic system repressurised once.
That was when we let it down to replace the suspension arm bearings.
Moulton had a Metro that he had linked the Hydragas units fore and aft on, as the system was supposed to work. Everyone who tested it reckon it was vastly superior to the isolated unit version shipped by B/L.
The problem with both Hydrolastic and Hydragas was that tuning the suspension for spring rate, rebound and damping involved changing the valves in the units which, in turn, required the system to be depressurised and repressurised. This meant that fine tuning in development took significantly longer for each iteration than a conventional spring and damper arrangement, either of which can be swapped in minutes.
The swan song of Hydragas was on the MGF, with isolated units accompanied by conventional dampers to reduce development time.
I still reckon that, on a bigger car, those hydrolastic and hydragas systems provided the best rides of the period. My friends used to fight over who got to come with me in the 1800 for the comfort, even in the 1980s. For a car then getting on for two decades old to still be considered more comfortable than more modern machinery must mean that Alex got something right.....
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>> As well as being the progenitor of
>> small wheeled bikes ............
What was the point/advantage of having such small wheels?
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>> (trans)portability
>>
That is true, A diesel submarine I was in during the 60s carried a small wheeled folding Moulton bike for the postie to use, at least that was the excuse, it was used as a handy run about when in harbour.
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>> What was the point/advantage of having such small wheels?
>>
From the Moulton Bicycle website -
Small wheels with high pressure tyres have been integral to the Moulton design from the beginning. The combination of the lower rolling resistance of high pressure tyres and the lower aerodynamic drag of small wheels, allows the bicycle to go faster with less effort.
In contrast to large bicycle wheels, the smaller Moulton wheels are immensely strong. Their lower moment of inertia allows faster acceleration and more responsive steering. Smaller wheels also reduce the overall length of the bicycle, making it compact and easier to transport.
www.moultonbicycles.co.uk/features.html
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>> >> What was the point/advantage of having such small wheels?
>> >>
>>
>> From the Moulton Bicycle website -
>>
>> Small wheels with high pressure tyres have been integral to the Moulton design from the
>> beginning. The combination of the lower rolling resistance of high pressure tyres and the lower
>> aerodynamic drag of small wheels, allows the bicycle to go faster with less effort.
>>
Yeah! Right!
That why all road and racing cyclists use small wheel bikes?
Not.
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>> I've just come across this. hyperphysics.phy-astr.gsu.edu/hbase/mechanics/bicycle.html
>> And this. hyperphysics.phy-astr.gsu.edu/hbase/rotv2.html#rvec4
>>
Clicking on all the blue coloured links takes me back 50 years. I can remember studying it, but I can'r remember anything else about it! I do remember the word "precession" though.
Last edited by: L'escargot on Tue 11 Dec 12 at 10:08
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>> Yeah! Right!
>>
>> That why all road and racing cyclists use small wheel bikes?
>>
>> Not.
You're quite wrong, but you can do your own research.
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Some interesting stuff here: www.bikeforums.net/archive/index.php/t-474185.html
"Most world speed records are set on small wheels" :o
Last edited by: Focusless on Tue 11 Dec 12 at 10:10
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>> Some interesting stuff here: www.bikeforums.net/archive/index.php/t-474185.html
After reading all that, my head is spinning faster than a bicycle wheel!
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>> Some interesting stuff here: www.bikeforums.net/archive/index.php/t-474185.html
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>> "Most world speed records are set on small wheels" :o
For an upright riding position.
Recumbents are faster still, and you don't see those in the TdF either.
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Small wheel bikes are not used in racing because they don't handle very well.
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>> Small wheel bikes are not used in racing because they don't handle very well.
Isn't it just race cycling regulations?
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>> Small wheel bikes are not used in racing because they don't handle very well.
They are certainly different, and I don't think my Brompton is as safe in the wet as my large wheeled hybrid, though it's faster for me. But I wonder why the governing body saw fit to ban them from races?
Rule 1.3.018. “Wheels of the bicycle may vary in diameter between 70 cm maximum and 55 minimum, including tubular type...
From here -
www.4horses.me.uk/B/bicycles.html
Small wheels aren't banned from many types of competition. But there is a host of reasons I imagine, not least tradition and the large user base for large wheeled bikes, and the memory of some of the horrible small wheeled bikes produced.
The Hadland link in the above page is now dead. The material referred to is here I think -
hadland.wordpress.com/2012/06/25/small-wheels-for-adult-bicycles/
Last edited by: Manatee on Tue 11 Dec 12 at 11:05
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Wouldn't a larger diameter wheel have less distortion of the tyre as it rotates and thus a lower rolling resistance than a smaller tyre travelling at the same speed?
vs.
Larger wheels cause more aerodynamic drag due to higher frontal area and drag at the longer spokes.
Depending on which causes more of an effect would mean which could travel fastest.
Maybe a gigantic rear wheel and tiny front wheel would have the best of both worlds, although I don't remember my mate's Raleigh Chopper being as fast as my Grifter.
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>> Maybe a gigantic rear wheel and tiny front wheel would have the best of both
>> worlds, ............
Bikes used to be just the opposite at one time!
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Apparently more than a few deaths occured as people went 'over the handlebars' of their penny-farthings.
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>> Recumbents are faster still, and you don't see those in the TdF either.
Because they dont handle well, go round corners very fast, the the riders prone postion does not provide full lung function or capacity.
In fact it is the height of stupidity
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>>In fact it is the height of stupidity
I'd love to see a TdF mountain stage being done on recumbents... more death than Group B rallying.
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>> >>In fact it is the height of stupidity
>>
>> I'd love to see a TdF mountain stage being done on recumbents... more death than
>> Group B rallying.
Ah, but the Group Bs were the fastest...
There's a lot of variation in recumbent designs. Some of them don't climb very well at all. But they are fast and no doubt a design could be developed for that sort of event. ISTR Lance Armstrong said he'd try one if they weren't banned (he'd try anything, as we now know, allegedly).
That said, the Tour and the tactics, the peloton, pacing and team riding, is all evolved around uprights - I don't think you could mix them up very easily.
What puts me off the idea of a recumbent, apart from the price, is my perception that they are less safe. But people who use them usually say they get more consideration from other road users.
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>> What puts me off the idea of a recumbent, apart from the price, is my
>> perception that they are less safe. But people who use them usually say they get
>> more consideration from other road users.
Because they have a smaller frontal area and they're so low down they're not as visible to other road users.
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Depends... www.cruzbike.com/sofrider (front wheel drive!)
Last edited by: Focusless on Tue 11 Dec 12 at 13:43
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Looks like tight turns could be a problem.
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A lot of technological advances which make bicycles faster and more efficient are banned by the UCI because of their absurd obsession with keeping bikes as close as possible to those of the seventies. Thus we have £99 clunkers being wheeled out of Hafords with superior braking systems to the out-dated rim brakes still fitted to race bikes, something which should have been consigned to the bin two decades ago.
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Alex Moulton RIP - henry k
