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Has everyone seen the giraffe bike Paul Brodie built?
https://www.brodiebicycles.com/brodie-b ... -cycleexif
Has everyone seen the giraffe bike Paul Brodie built?
https://www.brodiebicycles.com/brodie-b ... -cycleexif
Did the Victorians know more about bicycle design?
- Thread starter GrahamJohnWallace
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Yes, absolutely wonderful, I wish you could buy bikes like this. So much more interesting than modern bikes. It would be a great bike to take around the local trail centre. Imagine just how far you could hang off the back on the 'drop-offs'.
It also has a suspension seat-post and a front brake that also clears mud from the tyre. :shock:
Retro_Roy":2x8tkyrp said:
Yes, absolutely wonderful, I wish you could buy bikes like this. So much more interesting than modern bikes. It would be a great bike to take around the local trail centre. Imagine just how far you could hang off the back on the 'drop-offs'.
It also has a suspension seat-post and a front brake that also clears mud from the tyre. :shock:Attachments
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The lack of wheel wobble at such a low speed illustrates the fact that tall top heavy unstable objects fall over more slowly than short unstable objects despite their lower centre of gravity. That bike probably has a bottom bracket height of around 30 inches. Yet some modern trail-bike manufacturers state that their new bikes are much more stable because they have dropped the bottom bracket less than an inch when compared to their older model.
If such manufacturers are actually referring to longitudinal-stability then an inch would make little difference on a fashionable long wheelbase bike. Fitting anti-dive front suspension or anti-jack rear suspension would have a far greater impact. I use dropper posts to improve longitudinal-stability because, with the saddle out of the way, its so much easier to quickly move your body weight to where its needed. Trials bicycles don't need long wheelbases and low bottom brackets, just a rider who knows when and where to shift his body weight.
Is it that modern trail-bikes are designed to be used by unskilful riders who stay in the saddle and do relatively little in terms of moving their bodyweight around? If so, are these bikes the way they are so that they crash through technical sections, relying heavily on their strength and suspension in order to get through? The bike does all the work whilst the rider takes the credit?
That's something I notice with my full suspension bikes. Though I can ride an un-sprung bike down hill, over rough terrain quite quickly, it takes a lot more effort and skill. :?
I think the biggest danger is that the cars might crash into each other whilst they are distracted by the presence of the penny farthing. No car who drove into the penny farthing could say that they didn't see him coming. :shock:M-Power":1kimyl9c said:Cant help it but watching this chap in London traffic gives me palpitations
https://youtu.be/T_QyTnGPmEc
The lack of wheel wobble at such a low speed illustrates the fact that tall top heavy unstable objects fall over more slowly than short unstable objects despite their lower centre of gravity. That bike probably has a bottom bracket height of around 30 inches. Yet some modern trail-bike manufacturers state that their new bikes are much more stable because they have dropped the bottom bracket less than an inch when compared to their older model.
If such manufacturers are actually referring to longitudinal-stability then an inch would make little difference on a fashionable long wheelbase bike. Fitting anti-dive front suspension or anti-jack rear suspension would have a far greater impact. I use dropper posts to improve longitudinal-stability because, with the saddle out of the way, its so much easier to quickly move your body weight to where its needed. Trials bicycles don't need long wheelbases and low bottom brackets, just a rider who knows when and where to shift his body weight.
Is it that modern trail-bikes are designed to be used by unskilful riders who stay in the saddle and do relatively little in terms of moving their bodyweight around? If so, are these bikes the way they are so that they crash through technical sections, relying heavily on their strength and suspension in order to get through? The bike does all the work whilst the rider takes the credit?
That's something I notice with my full suspension bikes. Though I can ride an un-sprung bike down hill, over rough terrain quite quickly, it takes a lot more effort and skill. :?
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All my bikes are short wheelbase, steep geometry bikes with higher than normal bottom brackets. Even the modern full suspension ones. Though most of my riding is on 'natural' trails or completely off trail, I do ride the occasional trail centre 'black run' and manage ok. Admittedly I take my time and ride at my own pace and no course records were ever threatened.greencat":ibvgxwt1 said:
Way back I did take my old 1983 Cleland Aventura down what was described as a 'black-run'. By having the saddle right down for the entire run, hanging right off the back for the 'drop-offs' and climbing out of the saddle I managed, to my surprise to clear it without any trouble. Again, no records where broken apart from possibly the slowest time ever.
Perhaps I should take it back to a trail-centre when they reopen? However, I will need to sort out a problem with the brakes first.
I think that you can ride over technical terrain on low tech simple bike (eg BMX) as long as its design allows the rider to move his body weight around quickly.
However, you can only bunny hop, lift the front end etc, quickly enough when going slowly. At speed you need mechanisms to absorb the shock and keep the wheels on the ground etc. There are more skill involved in the former and more thrills involved in the latter.
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In terms of biomechanics the issue here is about feedback loops. How quickly a bike feeds back a loss of balance to the rider and how much time the rider has to respond.
When a bicycle unbalances to the right, the rider responds by steering to the left. If the rider gets the correction right the balance (equilibrium) is regained. If he fails to make the right amount of correction then the bike will either continue to fall over, or if he/she overcompensates, start to fall the other way.
In simple terms, it is the contact patch of the front wheel and its relationship to the combined weight of the bicycle & rider acting at the Centre of Gravity (CoG) that controls balance.
The closer the front wheel contact point to the CoG the quicker the bike will respond to steering corrections. A bike with these characteristics is usually said to have 'twitchy' handling. Conversely, the further away the CoG the slower the bike will react and the longer the rider has to repond.
So is it best to have a bike where the response to steering corrections is swift and direct? or slow and woolly?
It depends on the skill of the rider and nature of the ground being ridden over. On smooth grippy surfaces a quick response to corrective steering is desirable. On rough slippery surfaces however it is better to have a bike that is both slow to unbalance, and gives the rider more time to respond with the appropriate amount of correction.
By moving their weight about strategically, a rider can get both characteristics from the same bike. The problem with many older MTBs is that they were designed to be ridden mostly in the saddle. The same is probably true of modern gravel bikes?
Theoretically, lifting your weight off the saddle of a road bike will make it more twitchy as the bodyweight moves forward onto the pedals. Great for the extra control required for track-stands though.
In terms of biomechanics the issue here is about feedback loops. How quickly a bike feeds back a loss of balance to the rider and how much time the rider has to respond.
When a bicycle unbalances to the right, the rider responds by steering to the left. If the rider gets the correction right the balance (equilibrium) is regained. If he fails to make the right amount of correction then the bike will either continue to fall over, or if he/she overcompensates, start to fall the other way.
In simple terms, it is the contact patch of the front wheel and its relationship to the combined weight of the bicycle & rider acting at the Centre of Gravity (CoG) that controls balance.
The closer the front wheel contact point to the CoG the quicker the bike will respond to steering corrections. A bike with these characteristics is usually said to have 'twitchy' handling. Conversely, the further away the CoG the slower the bike will react and the longer the rider has to repond.
So is it best to have a bike where the response to steering corrections is swift and direct? or slow and woolly?
It depends on the skill of the rider and nature of the ground being ridden over. On smooth grippy surfaces a quick response to corrective steering is desirable. On rough slippery surfaces however it is better to have a bike that is both slow to unbalance, and gives the rider more time to respond with the appropriate amount of correction.
By moving their weight about strategically, a rider can get both characteristics from the same bike. The problem with many older MTBs is that they were designed to be ridden mostly in the saddle. The same is probably true of modern gravel bikes?
Theoretically, lifting your weight off the saddle of a road bike will make it more twitchy as the bodyweight moves forward onto the pedals. Great for the extra control required for track-stands though.
GrahamJohnWallace":2y4y90h7 said:
While I've happily ridden my Brompton down some trails, I've yet to see anyone bring a retrobike to Red Bull Rampage or even use one to tackle the 8 foot gap jumps the local kids have built in the woods. I don't doubt that someone could (I watched Sam Pilgrim riding a rigid Walmart bike down Whistler a while back), but I think it would be a very rare rider. The sport has changed almost beyond recognition in the last 2-3 decades, riders and bikes have got more capable - and not just in terms of speed. Post of video of the Cleland tackling the black trail next time you are out there - it would be cool to see it in action and I'd love to see the expressions on other bikers.
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BITD, I did try to jump my Brompton over a trench dug in the road. Not a good idea as it was the original type where the rear triangle did not lock onto the seat-tube, and the back of the bike tried to fold up in mid air.greencat":2e2rdrol said:
I have little doubt that I am out of touch with recent trail centre developments. I also assume that some black-runs are more difficult than others.
I would like to take a Cleland around a modern trail-centre, preferably a bike fitted with a modern dropper seat-post. I do occasionally take a Cleland along on a local MTB club ride. Initially, I am usually greeted with disbelief, sometimes bordering on polite ridicule. However, I usually manage to keep up. Once I received a spontaneous round of applause from the other riders when I cleared a technical downhill course they had built. I think that they were expecting me to kill myself.
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Oh look 'modern bikes are betterer' again - no, no they're not, they're just different. Nobody is going to watch you or your sport if its just a procession.
In the pre-internet days, there was no Youtube to ape to, just your mates and the jumps you did which got bigger and bigger as the story got passed around.
Its forgotten that the roads we have now are a result of cycling. Victorian bikes and riders were tough as the roads were simply not up to much. A Brompton would have been a very bad bicycle to ride back then.
For a while it felt like trail centres were just part an arms race - they got gnarlier so the bikes got gnarlier or is it the bikes got gnarlier first - whatever, it all got very silly. Unless you got tooled up, you couldnt just 'go for a ride'. Then you have to drive to them and its all very sanitised no matter how big the drops are. Trying to sling an 1980's or 1990's, even a 2000s MTB around one is not the fun it should be.
The fun part is taking an old bike out and seeing what you and the bike can still actually do. It would be fun to try the Victorian bat shit crazy stuff because it would be fun
Fun!
FUN I tells ya!
In the pre-internet days, there was no Youtube to ape to, just your mates and the jumps you did which got bigger and bigger as the story got passed around.
Its forgotten that the roads we have now are a result of cycling. Victorian bikes and riders were tough as the roads were simply not up to much. A Brompton would have been a very bad bicycle to ride back then.
For a while it felt like trail centres were just part an arms race - they got gnarlier so the bikes got gnarlier or is it the bikes got gnarlier first - whatever, it all got very silly. Unless you got tooled up, you couldnt just 'go for a ride'. Then you have to drive to them and its all very sanitised no matter how big the drops are. Trying to sling an 1980's or 1990's, even a 2000s MTB around one is not the fun it should be.
The fun part is taking an old bike out and seeing what you and the bike can still actually do. It would be fun to try the Victorian bat shit crazy stuff because it would be fun
Fun!
FUN I tells ya!
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I am lucky as I live in the countryside and can easily go riding off road without having to drive. I can appreciate the need for trail-centres situated close to cities as not everybody can live in areas close to good natural trails. In the UK, the very first off-road riding experiences where created on the cleared bombsites of WW2. The big difference between now and then is that back then you only needed a bike rescued from a ditch to have fun. Now you need an expensive, specialist trails bike.legrandefromage":2lsaig1i said:
A Victorian solid tyre high wheeler riding in the city would have to contend with uneven cobbles, horse dung, and worst of all, tram lines. From my limited experience of trail centre riding is does appear that offer a 'sanitised' riding experience. Their designed surfaces are smoother than natural trails and I don't seem to have any adverse cambers. They are far better maintained, drained and free of the ruts, roots, branches, quagmires, loose and slippery surfaces that are commonplace on bridlepaths.
Trail centres are designed to allow riders to experience the thrill of speed in as safe a way as possible and there's nothing wrong with that. But bikes designed for fast trail-centre use are not optimised for the long distance natural trails that interest me. For me the relatively simple 'old bikes' I have been riding for decades are hard to beat though I do fit them with modern tyres, suspension/dropper seat-posts etc. I do own some very nice well engineered modern XC bikes, but they get far less use than the old bikes.
After all these years of engineering development and given the vast number of modern bikes on the market, I should be able to go out and buy something similar that is lighter and stronger but I can't.
In nature competition results in diversity. Market forces however seem to result in reduced choice as big manufacturers all follow the latest trends.
Compared to modern bicycles, Victorian machines where crudely made from basic materials but the sheer variety of designs on offer was amazing. If we could combine the diversity of Victorian design thinking with the amazing capabilities of modern engineering and production processes then think what fun could be had.
What could this bike become if it were re engineered from today's marerials?
This bike uses a Watt's straight line linkage connected to a single spring in tension to suspend the rider above the wheels. The advantage of this is that there will be no front end dive when braking and no rear end squat when accelerating. If fitted with a pre-loaded spring, the suspension could be completely isolated from the transmission forces.
