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  1. #1
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    Strong enough frame?

    I'm planning a first, short tour at the end of the year, just ducking north to south across Tasmania. I'll do it comfortably in a couple of days, maybe cruise and do it very slowly in three, but overall it's not that epic (some of you may not even class it as a tour!). Of my bikes I would plan to take my current commuter, a '93 Giant Allegre, made of Giant proprietary "Lightweight Racing Tubing" or some such. Lightweight is a relative term; I've got a '91 Merckx Corsa Extra 60cm, which I believe to be Columbus SP, and it is probably a similar weight, maybe a touch heavier in the frame. It's got wheels which I'm sure will be the ticket, Mavic Open 4 CD (predecessor to Open Pros, proper eyeleted nipple holes, solid equipment) laced to mint Suntour SL hubs.

    So, I have two questions, will my frame/wheels die under load? and whats the best solution to dealing with the lack of rack mounts? Tubus QR skewer option or Old Man Mountain?

    I'll be flying across packing light will be necessitated by check-in weight limits (figure 17kg or so is already down with the bike packed in cardboard), is 10-12kg (22-26 pound odd I guess) safe on a non-touring specific bike?

  2. #2
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    Sounds fun! You should be fine. Take which ever bike has the lower gearing, and use the stronger wheels (i have the impression either bike could use the wheels). Pack as light as you can - lots of hostels in Tasmania, maybe you could get away w/o camping gear?

    I put the Tubus Fly with the quickrelease adaptor on my road bike, and was very satisfied with it on a short lightly loaded credit card tour. I haven't used OMM so I can't compare.

    I didn't make it to the middle of Tassie (it was snowing in February!!!) but if you happen to ride the east coast, Freycinet and Maria Island are both totally awesome - get off your bike and do some hiking.
    ...

  3. #3
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    think about it this way: would the frame fail if you were 22-26 pounds heavier?

    youll be absolutely fine

    and +1 on the fly rack.

  4. #4
    Senior Member Wogster's Avatar
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    Quote Originally Posted by lachy94 View Post
    I'm planning a first, short tour at the end of the year, just ducking north to south across Tasmania. I'll do it comfortably in a couple of days, maybe cruise and do it very slowly in three, but overall it's not that epic (some of you may not even class it as a tour!). Of my bikes I would plan to take my current commuter, a '93 Giant Allegre, made of Giant proprietary "Lightweight Racing Tubing" or some such. Lightweight is a relative term; I've got a '91 Merckx Corsa Extra 60cm, which I believe to be Columbus SP, and it is probably a similar weight, maybe a touch heavier in the frame. It's got wheels which I'm sure will be the ticket, Mavic Open 4 CD (predecessor to Open Pros, proper eyeleted nipple holes, solid equipment) laced to mint Suntour SL hubs.

    So, I have two questions, will my frame/wheels die under load? and whats the best solution to dealing with the lack of rack mounts? Tubus QR skewer option or Old Man Mountain?

    I'll be flying across packing light will be necessitated by check-in weight limits (figure 17kg or so is already down with the bike packed in cardboard), is 10-12kg (22-26 pound odd I guess) safe on a non-touring specific bike?
    The big issue with bicycles and weight is the weight of the load, the biggest part of that load is the "engine"

    A rider who is under 75kg probably will not have any issues with wheels or frame, a rider who is 150kg and over may have wheel issues. Frames, unless they are really light weight racing frames are sufficiently engineered to handle all, but the heaviest riders, that includes, surprisingly many of the carbon fibre reinforced plastic frames. Yes there are 150kg riders on carbon without ill effect.

    With wheels there are a couple of things to remember, as the load weight increases or spoke count decreases, spoke tension becomes more critical as does the amount of flex in the rims (but to a lesser degree). There are 100kg riders who have 32 spoke wheels that pop a spoke every 25km, and 150kg riders on 24 spoke wheels that wear out rims without popping a spoke. If your worried, get a wheel builder to properly tension and true your wheels before you head out.

  5. #5
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    Quote Originally Posted by Wogsterca View Post
    ... that includes, surprisingly many of the carbon fibre reinforced plastic frames. ....
    huh?
    ...

  6. #6
    Senior Member Wogster's Avatar
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    Quote Originally Posted by valygrl View Post
    huh?
    Carbon frames are actually carbon fibre reinforced plastic frames, it's made by forming a thin thread, a chain of carbon molecules, this is then twisted into a "yarn" which is weaved into a cloth. The bicycle manufacturer then takes this cloth and impregnates it with a liquid plastic resin, if forming a tube then they would roll a small amount of the cloth into a tube, then coat it with the plastic, then build this up into layers until they get the right diameter of tube they want.

    The carbon fibre thread is very expensive, making the cloth horrifically expensive. The advantage to the bicycle manufacturer is that the material can be formed into all kinds of exotic shapes that can not be easily made using metal tubing. There is also no need for welds or joints in the material, as long as the cloth is cut so that joints between layers do not line up. For most products there is considerably more plastic then carbon. This is why it's more properly called carbon fibre reinforced plastic. The material does not rust, it doesn't suffer from stress fractures, but can be affected by shock.

  7. #7
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    Sounds like i'm in the clear . I'm 6'3", so even though I'm very lean I'm still 78kg or so (179 pound odd), but I suppose you're right, if someone weighing 100kg wanted to ride my bike I'm sure they could it ok, so that's cool. Another concern I have is the tight clearance of the rear wheel, and the short chainstays, am I going to be hitting my panniers with my feet all the time?

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