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clubman

Member since Jun 2008 • Last active Dec 2019

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  • in Bikes & Bits
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    Jeff 80.
    The jumping problem sounds to me like an incompatible chain and sprocket rather than a malfunctioning derailleur. Even the best modern mechs won't stop the chain jumping when there is wear on the chain or the sprocket, and jumping on one sprocket is typical, since it's the most worn one that jumps.

    Of course, if you're using a new block and a new chain then I'm wrong, but if one is new and the other is not this could well be your problem.

  • in Bikes & Bits
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    These 'mudguards' never gave any protection, and racing bikes never have mudguards. I suggest you take them off and forget them.

    I'm sure we'll all be most interested to hear how you get on with the cambio corsa on the road.

  • in Bikes & Bits
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    I've just re-read these posts and I'm beginning to think I can see an answer. I believe the problem is that the chain is too long, and this causes the jockey cage to be too upright to allow the bottom sprocket to engage. I'm assuming here that the main problem is getting onto that bottom cog - if it won't change onto the others we'll have to think again.

    It's quite clear to me that the main use for these mechs is for us to get pleasure by trying to figure out how to make them work - actually using them isn't nearly so much fun.

  • in Bikes & Bits
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    I have set up a Simplex TdF and made it work fairly well (which is possibly as well as they ever work!), but I certainly would not claim to be an expert.

    I'm not clear about exactly what your problem is - are you saying that if you have the chain tension correct it won't change, or that you can't get the tension right?

    I suppose you have got the jockey cage the right way up - it's not rare to see them fitted upside down so that the the top jockey wheel is too far away from the sprockets, which might cause the sort of problems you describe.

    It's worth mentioning that these old 'plunger' mechs were never easy to set up, especially in comparison with parallelogram gears, and I'm talking here about a time when they were current and new spares were readily available.

  • in General
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    I'm rather expecting that lap top is going to turn up soon.......

    "I just thought I'd give those cushions on the settee a bit of a tidy up, and what d'you know, there it was down the back of the sofa!"

  • in Bikes & Bits
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    Assuming your block is like all the others I've seen:

    There should be a disc just outside the damaged slots which the removing tool would have fitted into. The disc is often stamped "unscrew" with an arrow pointing clockwise since it normally has a lefthand thread. This disc is the outer cone of the freewheel bearing and should have two small holes into which you can insert a punch or the edge of a chisel to unscrew the disc. Once this is off the outer part of the block with the sprockets comes away revealing the centre which can be removed in a vice.

    And if you can re-assemble it afterwards you're a cleverer person than I am.

  • in Bikes & Bits
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    I happen to have a spare block (if I can find it, that is) 16, 19,22. If you can repair or replace the mech you can have it.
    Remove the old block by dismantling it and then unscrewing the centre holding it in a bench vice. Do not cut the spokes to remove the damaged rim before doing this!

    Personally, I would want to convert this machine to 5 speed, since I think a 3 speed derailleur is more trouble than it's worth, unless you can use a wide ratio double chain ring set up. The TdF will not cope with this.

  • in Bikes & Bits
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    This was an all too well known failure back in the day.

    It was usually caused by the arm of the mecahism getting bent (often by someone other than the owner!), but faulty adjustment was certainly another cause. Benelux and Huret were just as bad, and this problem was perhaps the main thing which made the Campag Gran Sport such a revelation. With a Campag, if someone knocked your bike over it would only push the mech over against the spring - as soon as you picked it up it just sprang back to where it was before with no harm done.

    In this case, I note that the block is very close to the hub flange, which meant there was no margin of error to avoid this disaster - a spacer (or two) behind that block might have secured a longer life for the unfortunate TdF mech.

  • in Bikes & Bits
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    It's not obvious from the photo, but on the Aussie Hurlen the back mudguard lower stays are made up from wire coat hangers - with the mounting on the seat stay in that position you need very long stays and I couldn't find any. My effort is not quite as good as the originals since the wire is slightly thinner and less rigid, but they've kept the mudguard in place for some years now.

  • in Bikes & Bits
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    You could be right about those lugs - I don't know what they are, but the bottom bracket is standard size, so that's not much help for indentification.

    Sealing your BB bearing might be ok for the bearing, but it's not a solution for the problem - perhaps your LBS is hoping to sell you a new frame after yours has rusted through!

    I think this problem is almost always caused by lack of a back mudguard, but you might take the extra precaution of silicon sealer around the seat bolt area.

    It used to be normal practice (towards the end of the unsealed BB era in the 70's and 80's) to fit a plastic seal between the BB cups. You may still be able to find these at cycle jumbles, but if not it's possible to make one from a plastic bottle.

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