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PostPosted: Sat Jan 03, 2009 2:10 pm 
retrobike rider
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And to think Kona claimed to have invented the sloping top tube!

It's interesting that the horizontal braces between the bottom of the head tube and the top of the seat tube were thought necessary. We now know they're not necessary of course, but I wonder if they were provided 'to be on the safe side', or whether there were initial failures without them? Or were the tubes available then not stiff enough for off-road without reinforcement?


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 Post subject: Braces
PostPosted: Sat Jan 03, 2009 3:26 pm 
retrobike rider
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Modern bikes solve the problem of the forces from the forks, twisting and ultimately breaking the frame, with the use of re-enforced headstock/downtube joints (both internal and external).

Using braces to re-triangulate the frame is simply a geometric solution to the same problem.

Which is best? That’s down to issues of: weight, cost-effectiveness and aesthetics.

My understanding is that the cross-brace/s were introduced as a safety precaution because this problem is made worse by the combination of larger hub-brake forces, and an extra long headstock.

Remember that oversize/ strengthened tube-sets were not available at this time and the Clelands were made from standard Reynolds 531ST.

Picture = 1979 (un-braced Cleland)


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File comment: 1979 (un-braced Cleland)
1979rangeriderweb_179_small_956.jpg
1979rangeriderweb_179_small_956.jpg [ 165.96 KiB | Viewed 2271 times ]


Last edited by GrahamJohnWallace on Sat Jan 03, 2009 4:09 pm, edited 1 time in total.
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PostPosted: Sat Jan 03, 2009 4:02 pm 
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Thanks for the comments,

Yes I agree about the saddle! was just one that was around at the time of the photos. The bike came with no saddle, but i think a brooks would suit it best or a turbo.

I will have to get my Dad to join up to this forum if he's not already a member! he has a collection of retro mtbs.

I know he visited David Wrath-Sharman in Wales a few years ago whilst tracking down spare parts for the rebuild. I think the new rims came from him. The bike originally had a different front brake, possibly from a moped? This was replaced as it did not work that well and the SA front hub matched the rear nicely.

Will see if a frame number is visible, quite likely now its been repainted.

Would really like to get hold of original graphics for the down-tube and head-badge? does anyone have these, or artwork.


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PostPosted: Sat Jan 03, 2009 4:26 pm 
retrobike rider
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I do have one complete sheet of Cleland graphic transfers (somewhere?).
Geoff Apps who designed the bikes and their graphics, may have the original artwork. I will discuss this with him.

It would be a good idea to have some more printed instead of using up the last remaining sheets.


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PostPosted: Sat Jan 03, 2009 5:50 pm 
retrobike rider
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GrahamJohnWallace wrote:
It would be a good idea to have some more printed instead of using up the last remaining sheets.

As you may already know, Gil_M on this website is the man.


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PostPosted: Sat Jan 03, 2009 7:11 pm 
retrobike rider
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These pictures show Cleland Aventuras in with their "as supplied" components. The brakes are French ' LeLeu' moped hub-brakes. Mudgard colours and styles varied from bike to bike and various parts were often colour coordinated to the frame or each other.

Some earlier Aventuras were not supplied with the full Shimano DeoreXT groupset as this was not yet available.


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1983 Cleland Aventura.jpg
1983 Cleland Aventura.jpg [ 83.74 KiB | Viewed 2224 times ]
1984 Cleland Aventura.jpg
1984 Cleland Aventura.jpg [ 90.35 KiB | Viewed 2224 times ]


Last edited by GrahamJohnWallace on Thu Jan 08, 2009 9:44 pm, edited 1 time in total.
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PostPosted: Wed Jan 07, 2009 11:23 pm 
MacRetro rider
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Hello Rainard,

That's an astonishingly good restoration job being done on that Aventura!
The rear hub is a very rare Sturmey Archer, there were only twenty five pairs made made in 1986/7. The principle difference is the incorporation of a swing-cam, as per Dave Wrath-Sharman's design. The brake shoes are non-standard, but standard replacement items can be modified to fit. If you're interested, I have a matching front hub, which is part of the Clelandale Prototype, so it's laced into a 590 wheel. I was never very happy with these brakes, they worked very well most of the time, but sometimes would snatch violently, and lock on. And you never knew precisely when this would happen ~ no warning. Some very embarrassing moments. The standard SA (your front hub) were not much use at all in wet and muddy going. Completely unreliable. They may have been improved, but I doubt it. Nowadays, Shimano 'Roller Brakes' fit the bill very well indeed ~ in fact I'd go so far as to say they are as near perfect as you're likely to get.
The Chainset looks completely original, but where did you get those Speed Hakkapeliittas!?!?! They are the best tyres for Cleland style off-roading.
The saddle looks about right for a production model, because the buyer was most likely going to fit their own; you're quite right, a sprung and narrow Brooks, I think the model name was 'Champion'. However, the Cleland concept is ever practical and pragmatic, so, if that saddle is comfortable, then keep in on. However, it looks a little wide to me, because, with the Cleland you are supposed to be able to slide right off the back of the saddle.
And those handlebars won't let you do that, unless you've got very, very long arms! Yep, that handlebar set-up is very definitely not original, and goes against the principles of the Cleland Design; which is...
There is no 'perfect' design layout for a bicycle. People talk about a 'stable' design being desirable. But the fact is that a bicycle is completely unstable; you can't have a stable bicycle, you can only have a bike that is, at times, less unstable. Anyone telling you that their design is stable is talking bollocks. All aspects of bicycle design should take this into account and mitigate the instability. On analysis one can say that the principle means of controlling the instability is by being able to rapidly and easily shift the centre of gravity of the bicycle and rider, but of this combination, the rider is by far the greater part, so shifting the CG of the bike is of little use. The best way of shifting the CG of the rider is to place them on the machine so that their body weight can be readily moved forward or backward, or from side to side, or any combination or permutation of all of these. Placing the handlebar right above the steering axis and relatively near the saddle, with the saddle quite forward, achieves this facility. It also raises the rider to a very high riding position, which makes the CG much higher than the average machine. This flies in the face of conventional design 'wisdom' which says that a low CG is vital for a stable machine. This is simply not true ~ it does apply to vehicles that are inherantly stable (ie: a car) ~ but not to a machinne which falls over if you leave it alone. Here your manipulation of the CG is the rider's principle tool of manoeuvrability. If we see the CG as being at the end of a lever, then the longer that lever is, the less effort is required to manipulate it. The further it is from the ground (the fulcrum) the greater the leverage; you have to move it further, but it is easier to move it.
So, obviously, the previous owner who fitted that handlebar set-up, didn't understand this principle ~ it's like fitting a spoiler to a Range Rover!
The original handlebar was a CW 'Flat Top', but there are some jump bars now available which would fit the bill ~ Gusset 'Prison' for example ~ and using a very short 'BMX' clamp/stem. The Handlebars shown in the Advert were a pair of Renthal Trials bars, and only used on one machine.

Anyway, it will be great to see it completed ~ perhaps you or your father will be able to get over to the Birthday Ride at Wendover next December?


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PostPosted: Thu Jan 08, 2009 8:03 pm 
retrobike rider
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GeoffApps wrote:
The Handlebars shown in the Advert were a pair of Renthal Trials bars, and only used on one machine.


When Geoff says 'one machine' he means one Cleland Cycles' produced machine.

This is an English Cycles' produced version of Geoff's Range-Rider design.

It is worth remembering that the Clelands were inspired by trials-motorbikes and not by Marin-County' style bikes and their stretched-out riding positions.

Clelands have superb technical-terrain' abilities.

Whilst recently riding with Geoff through half-frozen mud, I was forced to get off and walk. This reminded me of the incredible technical-ability of these bikes, when in the hands of an expert rider.


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Bash84.jpg
Bash84.jpg [ 63.52 KiB | Viewed 2095 times ]


Last edited by GrahamJohnWallace on Thu Jan 08, 2009 9:47 pm, edited 3 times in total.
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PostPosted: Thu Jan 08, 2009 8:23 pm 
MacRetro rider
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It's worth pointing out that in the picture above the Cleland rider is climbing a one-in-two loose surfaced hill (about 33% I think), and at that point he has climbed about thirty yards.

Here's an example http://www.vimeo.com/2679372 of typical Cleland manoeuvrability, the flood is about 14-16" deep with rocks under the water ~ randomly placed, of course!


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PostPosted: Thu Jan 08, 2009 9:59 pm 
retrobike rider
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Cleland rider climbing a one-in-two loose surfaced hill

Another View


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