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PostPosted: Mon Dec 06, 2010 5:20 pm 
Gold Trader
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xeo wrote:
[quote=
I realise fashion has a part to play in the MTB world, but I wish people (the Yoof?) would realise that in the UK the majority of trails do not require long travel, then we might get more investment in creative and intelligent alternatives to "all mountain" bikes which have become the norm.


Agree, but all mountain bikes have become the "norm" due to the average rider having bigger asppriations than several years ago.

In my book, there are two types of mountain biking most commonly done in the UK (NOT including racing) these would be trail centre riding, & er, going out in the countryside, (something we all here know all about being "retrobikers")

Therefore i ride predominatly two types of mountain bike, the first being either one of my old school MTBs (when its dry!!) or my thrash hardtail with 100mm fork, or my (wait for it...!) "all mountain bike" ! a lapierre spicy, with, 6" travel, disc brakes & a 50mm stem ! (s**t the bed) & why you ask ? a few reasons ;

retro steed & hardtail for local through the woods, or up in them there hills.. (if i wana go for a "thrash/blast/rag" the hardtails best, much more fun)

OR

The Spicy for riding afan, cwmcarn, or the megavalanche. For wales, idealy, due my wanting to "go for it" (i ride/race DH) & push myself. You see its my attitude to my riding that effects what i ride. Im FULLY aware that i could ride my muddy fox seeker over Afan, but it wont be no way near as much fun! & besides, no matter what all you may think, the facts are that a four-bar linkage suspension (set up right) aint that half bad to ride!!! (shock horror) the only penalty being extra weight, but hey, im pretty fit, & all that crap is in the mind anyway. Mind you the only occasion it was not, was on a media demo ride with John Tomac @cwmcarn not long ago.. he was behind me, & steamrollered past me on (wait for it!!!) 6" travel bike! he was f**king flying up that first hill. :shock: haha!

Theres nought wrong with "fashion" we were all victims once, christ, you aint EVER gona catch me in bright yellow lycra any more! but ALL mountain bikes, ridden by all ages, are fine for the UK. just not every person.[/quote]

I am not claiming that there isn't a place for 6" travel bikes in the UK, of course there is and I only recently sold my Ellsworth Epiphany (5.25" travel 4 bar linkage). My point is that the majority of riders in the UK are relatively new to the sport and have started out riding on a 6" travel "all mountain" rig or even tried a hardtail. This is negative because most of them aren't as fit as John Tomac and will struggle up hills compared with a hardtail (I don't care what anyone says, even the most efficient full sus rig can not match a hard tail in the climbs with equally matched riders on board).

I was in the peak district a few weeks back and saw so many riders out on shiny new £3k all mountain rigs and when they returned from their rides, they were barely dirty. The enjoyment seemed to be coming from the purchase of a bike that was more expensive than their mates', rather than enjoying the riding itself.

If the magazines and fashionista's were a bit more balanced and educated new riders about buying an appropriate machine for the kind of riding they do, the market place would be more diverse and bikes like the Cleland wouldn't be so "unusual". ;)

I like modern bikes as much as retro and own both, I just think that the majority of modern bikes are clones of one another and would be extremely difficult to tell apart without their decals. Full sus bikes are pushed as "must have" because full sus bikes have many more components to wear out and therefore have many more bits to replace/upgrade, so generate more money for the manufacturer. I doubt we will see a huge number of carbon full sussers being ridden by enthuiasts in 20 years time!


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PostPosted: Mon Dec 06, 2010 6:04 pm 
Retro Guru

Joined: Wed Jun 14, 2006 3:35 pm
Posts: 420
Location: Newbury
shedfire wrote:
Been digging around a bit, cogitating, walking the dog... that sort of thing today.

Couple of things to throw in the air for discussion on topic.

1) DWS's "Big Blue" looks pretty normal to me. His bars are at about the same height as his saddle. Not way up in the air. - http://www.flickr.com/photos/thebc23/39 ... /lightbox/

2) I think the remit for Cleland's, and the "Gentlemans Offroad Bicycle" are very close to the bikes Jeff Jones is building. His bikes also add another dimension - multiple hand position bars. Jeff's bikes also have a rearward weight bias and a light front end.


Ahh hello sir (cristian formerly of HL's here - how you doing?)

DWS's, big blue, like Ronald Jeramey, has length. something the cleland doesnt (in the ride position..) Im familer with Jeff Jones, had a customer buy one a few years back, beautiful bikes. & give me rearward weight bias anyday, either that or a klunker. :)

Not sure that multi position handlebars are so great? especialy like the ones that resemble mini bmx type bars, wouldnt these give the rider to much adjustment, adversely affecting the overall ride ?

To what percentage could a bikes ride position be adjusted to within its geomerty capabilitys, without f**k*** up its intened use, & doing all sorts of wrong stuff ?!

I love your idea of a gentlemans bike though, & of course you'll get it right! :D (looking forward to stocking Ragley 2011 btw)

& Barny, i agree we wont see many people riding carbon full sussers in 20years time... they'll be on here, lamenting about them! but dont be so cynical! :D If we didnt have evolution, we wouldnt have had E-stays :wink:


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PostPosted: Mon Dec 06, 2010 6:14 pm 
Dirt Disciple

Joined: Sun Jun 27, 2010 8:36 am
Posts: 34
Oh. Cristian. Didn't expect to find you here :-)

I'm good. Hope you're well.


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PostPosted: Mon Dec 06, 2010 6:42 pm 
retrobike rider
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Existing mountain bikers may not be potential Cleland customers simply because they come with so many preconceptions with regards to what an effective off-road bike should be. And these preconceptions make them blinkered to equally valid alternative approaches.

These preconceptions, both valid and invalid, are extremely useful if we are to develop a good understanding of how our bikes are perceived. And this knowledge will then guide us as to how these bikes can be best marketed.

The biggest preconception of all is that Cleland style bikes are slow and only suitable for leisurely rides. It's true that they were never designed to be fast but because air resistance is not critical at average off-road speeds they are quite capable of keeping up with mountain bikes apart from hill climbs when the weight of the old bikes takes its toll. I should know, as I often run my 1983 and 1988 Clelands on rides alongside modern bikes whose riders aren't prepared to wait for slow coaches. In fact on certain types of terrain, soft sand, rough bridlepaths, sloppy mud, the ultra low presure tyres give the Clelands a distinct advantage.

Because they look slow and leisurely, these bikes are likely to be perceived as such, no matter the reality. You can't easily change preconceptions but I am determined that anyone that takes one of these bikes on the local mountain bike ride should not be disappointed by their turn of speed.


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PostPosted: Tue Dec 07, 2010 8:54 am 
MacRetro rider
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This is an interesting thread, which has thrown up a number of issues.

One such is bottom bracket height, and therefore centre of mass.

Conventional bicycle design theory suggests that a low bottom bracket and c/m give a bicycle design stability.

This theory assumes that a bicycle has the capability of being stable.

Can it?

Try a simple experiment: Stand next to your bicycle, holding it vertical. Step away from it and let go of it. What happens? Of course, it falls over. This is proof that a bicycle is inherently unstable.

Thus the aim of bicycle design is, inter alia, to accommodate this inherent instability, and control it to maintain balance.

As you cycle along your bicycle is constantly falling, to one side or the other. To accommodate this, you steer from side to side to maintain balance. You are probably not aware that this process is going on.

Now, if you've read this far, try another experiment: find a long piece of material, such as a broom handle or length of wood about four or five feet long. Attempt to balance it vertically on your open palm. Tricky, but do-able. Now try the same thing with a pen. More or less impossible.

This is because the centre of mass of the broom handle is further away from your hand than the c/m of the pen.

This distance is critical; the greater the distance, the more reaction time you have to adjust the balance of the broom handle, whereas the pen has fallen over before you can react to get it into balance again.

It's the same with a bicycle: your open palm represents the ground and the broom handle/pen represents a bicycle; your movements to maintain the balanced vertical position of the broomhandle/pen represent your use of the steering to maintain balance on a bicycle.

Unless, I'm a complete idiot, this knowledge tells me several things:
1) A bicycle is unstable, so the idea that any design feature (apart from a sidecar) will provide any degree of stability, is nonsense.
2) Very few people understand this, or have even given the concept a moment's thought.
3) Centre of mass is the 'tool' by which a bicycle rider maintains balance when riding a bicycle.
4) The further away the c/g is from the ground, the less effort is required to maintain balance, leading to greater efficiency and less rider fatigue over a longer haul.
5) I am probably banging my head against a brick wall.

This is by no means the whole story of the Cleland design.

This is only one of several bicycle design factors that I have given lots of thought to, and incorporated into my design, but which the vast majority of cyclists either disagree with or don't care to hear about.

To be honest, I would much rather keep this all to myself; just enjoy riding my bike and not have to explain all this stuff over and over again.

But I was brought up not to be selfish, and to share my sweeties...[/b]


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PostPosted: Tue Dec 07, 2010 11:34 am 
retrobike rider
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The bike stays upright because of the gyroscopic effect of the wheels turning. The faster the wheels are rotating, the greater the gyroscopic effect. That's why it doesn't fall over when you're moving, but it does want to fall over when you stop. You can keep it upright when stationary using balance, but you only need to use balance when there is little or no gyroscopic effect.

A low centre of gravity provides stability in cornering. Whenever any vehicle is cornering, the higher the centre of gravity, the greater the centrifugal force trying to make the vehicle topple over to the outside of the turn. A two-wheeled vehicle needs to be cranked over to the inside to counterbalance that force. The lower you can keep the CoG, the easier it will be to corner.

Surely this is only confirming experience. Everyone feels precarious when they get on a bike with a high bottom bracket or saddle. 29ers feel stable because of the greater gyroscopic effect of the bigger wheels. They don't have high bottom brackets. All designers use as low a bottom bracket height as they can get away with.


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PostPosted: Tue Dec 07, 2010 11:39 am 
Dirt Disciple

Joined: Sun Jun 27, 2010 8:36 am
Posts: 34
Actually, you're both right.

High BB's are more stable at (very) low speeds.

Low BB's are more stable at high(er) speeds.

At low speeds there's no (minimal) gyroscopic stability, so the balance situation is like the pole-on-your-finger thing.


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PostPosted: Tue Dec 07, 2010 12:52 pm 
Retro Guru

Joined: Wed Jun 14, 2006 3:35 pm
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Location: Newbury
"gyroscopic effect of the wheels turning" = forward motion & continued momentum ..

Now im no bike designer by any means, but the above simply imply that they play a huge part in the bi-cycle being stable, at any speed, & likewise BB height being very important, reletive to the intended design application. In which case the Cleland being a low speed bike (whats its best at) a higher BB being better. I still know that riding any bike off-road in such a bolt-up-right position aint good though ..

Guys, (Brant/geoff ect) im sorry this prob. bores the living crap out of you, & you know it all already. But I couldnt help it. My tiny ego & keyboard-champion-wantoness compells me to do so. :cry:


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PostPosted: Tue Dec 07, 2010 1:01 pm 
Retro Guru

Joined: Wed Jun 14, 2006 3:35 pm
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Location: Newbury
oh Hi Brant, btw - im great thanks, back behind a counter! check yer pm's

Cristian :)


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PostPosted: Tue Dec 07, 2010 2:09 pm 
MacRetro rider
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Joined: Mon Nov 10, 2008 10:39 pm
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Location: SE Scotland
This is were I part company with the rest of the world: a bicycle is not inherently stable under any circumstances whatsoever.

Whilst being ridden, at various speeds, certain factors affect its balance, and the ease with which it can be balanced, but it remains inherently unstable.

Any discussion about the stability of a bicycle in motion is, in my book, invalid. There is no stability to discuss. It doesn't exist.








...but then, the religious cannot understand the heretic.



(I suppose I'd better get on with my invention to catch people who fall off the edge of the world)


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