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PostPosted: Sat Sep 08, 2012 11:39 pm 
retrobike rider
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highlands
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Are there lots of restrictions regarding the designs, like with the bikes?

Thankfully not...3 wheels, big at the back, small at the front, one size of pushrim per chair (ie one fixed gear), feet don't touch the ground, no fairings, commercially available, steering in races over 100, brakes over 400m.
That's pretty much it, the rest of the rules are obsolete these days (bells, mirrors, 4 wheels, one arm drives etc.) Just 15 rules over 2 sides A4.

I've been working with UK Sport and BAe Systems developing them over the last couple of years, and we brushed up against several guys used to UCI and F1 regulations. They were completely flummoxed by not having all those picky little rules on everything to work against.

All the best,


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PostPosted: Sat Sep 08, 2012 11:48 pm 
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That is interesting, thanks. It was a subject of conversation over dinner the other night, and now I have it from the horse's mouth!

I am looking at constructing something lightweight in a carbon flavour for ease of portability. Having dealt with wheelchairs and mobility aids over many years I am astonished at the cost versus low tech of the run of the mill equipment.

One thing the paralympics might influence is the sexiness of wheelchairs, adapted cycles, etc.

There is a chap near here who is making sexy wheelchairs.

I had a conversation with a chap on one of those wheelchairs that rear up on two wheels to allow eye to eye conversations, what a revelation.

Total respect for one of the true innovators on here!

:)


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PostPosted: Sun Sep 09, 2012 1:02 am 
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danson, you and David Weir have an awful lot to be proud of. Legends, both of you. Makes me truly proud to be British.


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PostPosted: Sun Sep 09, 2012 1:44 am 
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azaro wrote:
danson, you and David Weir have an awful lot to be proud of. Legends, both of you. Makes me truly proud to be British.


Hear hear!


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PostPosted: Sun Sep 09, 2012 10:19 am 
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danson67 wrote:
one size of pushrim per chair (ie one fixed gear)


Full of admiration for your work. Do the wheels have to be direct drive or is there feedom in how the hands interface with the wheel?


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PostPosted: Sun Sep 09, 2012 12:08 pm 
retrobike rider
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Direct Drive or freedom? Technically, both would be legal, but direct drive is the current norm...if you look at the wheels, there's a pushrim mounted on the outside, approximately 15" in diameter. This is covered in a high friction rubber. The athletes don't really push this, but punch it with their gloved hands, a bit like bowling a hoop along.

This pushrims vary a little in diameter between events and athletes between 14 and 16". The larger the rim, the lower the gear. Sprinters tend to use the larger rims to give a low gear for a good start. In the longer events, the start is less important, so they use a smaller rim (higher gear) to give better top end speed.

There have been attempts to cover th ewhole disc with a high friction coat, and push anywhere on it, but this tends to tie up the wheel, and lacks the consistent stroke that a single size of pushrim.

Sprinters often use the 4-spoke wheels, rather than the discs to get a crafty quick low gear push on the spoke near the rim at the start...but the commissaires are on the look out for this.

All the best,


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PostPosted: Sun Sep 09, 2012 12:13 pm 
retrobike rider
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Highlands:
Quote:
There is a chap near here who is making sexy wheelchairs.

Andrew Slorance at Carbon Black in Nairn? Certainly very nice, we'll see how the price and customisation options settle down. Carbon fabrication doesn't lend itself well to either being practical.

All the best,


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PostPosted: Sun Sep 09, 2012 2:07 pm 
Gold Trader / rb Rider / Special
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Do you make any other chairs? For instance the beefy rugby ones?
Also, for some users that do have use of legs, are they comfy to be tucked up under you for so long?


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PostPosted: Sun Sep 09, 2012 2:51 pm 
retrobike rider
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I don't make rugby chairs, but I do make day chairs...both Shelly Woods' and Dave's day chairs are also mine. Similarly, I've done rowing seats, waterski seats, handcycles and a few basketball chairs over the years.

We supply most of the chairs for the GB rugby team, but they're mostly Melrose from New Zealand or VMC from the States.

Making them is a possibility, but we're only a little comapny (6 of us) and I'm the only designed/fabricator, so expanding a product line is dfficult.

On the seating position...true, there aren't many elite long distance racers that have leg sensation. Cramping and poor circulation will always be a problem. A few double amps are coming up, but the longer races are dominated by SCI racers and Spina Bifida. At 1500m and above, racing is open class, so T54s will always dominate.

Hannah Cockcroft (T34), for example, can walk (albeit unsteadily) and would probably struggle to race, and would never medal, over 1500m+. Similarly, Tanni G-T raced at T53, and didn't win Para medals at the longer distances, as she had to race against the more able, faster, T54 classes (Mostly Chantal Peticlerc, from Canada).

At lower levels of the sport, there are often footplates etc, and the athletes (especially the CP T34 etc ones) sit in a much more conventional 90/90 degree position. More comfortable, but far less efficient.

All the best,


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PostPosted: Sun Sep 09, 2012 11:03 pm 
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danson67 wrote:
Highlands:
Quote:
There is a chap near here who is making sexy wheelchairs.

Andrew Slorance at Carbon Black in Nairn? Certainly very nice, we'll see how the price and customisation options settle down. Carbon fabrication doesn't lend itself well to either being practical.

All the best,


Yes of course, but we have the skills to do it here. I am constantly bemused by the importation of very basic steel chassis mobility scooters, etc. from China when we have all the skills and inginuity to create lightweight hi tech ones here, en masse, at competitve prices.

Remembering a lot of these aids are sold to the government at hugely inflated prices, I would love to see innovative companies taking advantage of what is a large market and making a real difference to the everyday practicalities of life with a disability.


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