Rear mech won't stay in gear - slips back to small cog - Campagnolo / Huret late '70s

no_helmet_king
no_helmet_king Posts: 10
edited April 2018 in Workshop
Hi guys,

This weekend I have replaced my gear cables with Jagwire stainless. I also took the time to swap out my chromed-steel Raleigh gear levers and fitted some Campagnolo Super Record from the same era. The bike is a 1979 Raleigh Grand Prix with 10-spd Huret Challenger rear derailleur. This is my first ever attempt at setting a rear derailleur.

I also fitted new alloy wheels to the bike and along with these a re-con freewheel, which is a very similar Maillard piece to my original one, but with slightly smaller cogs. With the new freewheel and no rear mech adjustment I found changing onto the larger cogs difficult and it would not select the largest cog. I remedied this when fitting the new gear cable, aligning the jockey-wheels to the big and small cogs using the 'limit' screws, though to achieve this both screws are set pretty much to their limit, as pictured.

I can now select the largest cog, but the problem I am having is the bike will not stay in any lower gear, it just slips straight back down to the smallest cog. With the finger-screw on the lever itself tightened up, the mech will stay in the 3 highest gears, but will still slip back off the two largest cogs. With the lever-screw tightened up to the point it can barely be moved, the mech will stay in the lower gears, but the second it loosens up the bike slips straight back down again.

Online guides / videos are confusing as they all show some late-model Shimano that looks like a spaceship and has a million features that my vintage Huret does not appear to have. I am confused... are my gear levers totally unusable? Is the smaller freewheel totally unsuitable? Or am I missing some vital piece of adjustment?

Any help / advice here would be much appreciated guys as going up hills is currently out of the question for me! :cry:

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Comments

  • whyamihere
    whyamihere Posts: 7,702
    It sounds like the problem is at the shifter end, not the mech. Think about the way it works - the shifter is moved to tension the cable, and should have sufficient friction to prevent this tension from being released until you want it to be. The spring in the derailleur is always working against the cable tension. You say that you've swapped out the shifter as well as all the other bits, I'm afraid you may have bought a dud.
  • Thanks for the reply, I feared as much. I think the fact I have caked the levers in WD40 for 'smoother' operation may have contributed to the lack of 'friction' in the friction-levers. For the time being I will run them as tight as possible so the bike is useable, but if the problem persists I guess I will look for some 'new-old-stock' replacement levers. The ones I have look OK, fingers crossed the WD40 is rubbed away and they become better... fingers crossed.
  • Monty Dog
    Monty Dog Posts: 20,614
    I doubt you'll have done any permanent damage as there's simply some friction washers inside.
    Make mine an Italian, with Campagnolo on the side..
  • svetty
    svetty Posts: 1,904
    If you aren't sure what you are doing maybe best take it to your LBS?
    FFS! Harden up and grow a pair :D
  • @Svetty ... harden up and grow pair... my 'LBS' (ooh how trendy) would be more than happy to show me how to set a rear derailluer up, but I thought I would ask on here as it is such a helpful forum.

    Anyway, I stripped the gear levers again, wiped the lube off and gave the friction plates a light beat-up with emery. Operation is now much better, I am able to select all gears and stay in them! The levers are tight but still useable while riding.

    I can see why these type of shifter are referred to as 'suicide levers' and people have switched up to ratcheting or indexed gear shifters. Oh well, this is my 40 yr-old beast and I shall stick with it... averaged 25.6kmh on way to work this morning... probably will be buying a helmet after all.
  • shaw8670
    shaw8670 Posts: 264
    If it plays up again, try carbon assembly paste. It provides smooth movement and a bit of grip. There is plenty of info online about it's properties.
    Greetings from the wet and windy North west
  • keef66
    keef66 Posts: 13,123
    I reluctantly gave up on some old Campag friction shifters when helping my son tart up an 80s Peugeot. I suspect a previous owner had lost some of the innards and they just wouldn't stay in the lower gears.

    Replaced them with some NOS Shimano 600 levers and they've been fine
  • veronese68
    veronese68 Posts: 27,311
    I can see why these type of shifter are referred to as 'suicide levers'
    I always thought suicide levers were the extra brake levers that were utterly rubbish and barely slowed you down. Like these:
    photo0714.jpg
  • keef66
    keef66 Posts: 13,123
    Veronese68 wrote:
    I can see why these type of shifter are referred to as 'suicide levers'
    I always thought suicide levers were the extra brake levers that were utterly rubbish and barely slowed you down. Like these:

    Me too. They were indeed utterly rubbish.

    Maybe the yoof wot have only ever known STI type shifters think faffing around with shifters on the downtube is suicidal? Whereas old codgers like me grew up with them and could select any gear precisely and without really thinking about it.

    If so, how do the millennials cope with extracting a bottle on the move or fishing something out of a jersey pocket?
  • veronese68
    veronese68 Posts: 27,311
    keef66 wrote:
    Maybe the yoof wot have only ever known STI type shifters think faffing around with shifters on the downtube is suicidal? Whereas old codgers like me grew up with them and could select any gear precisely and without really thinking about it.
    Could be. When we were on holiday in France a few years back the son of another family staying in the same place fell off his Dad's bike and broke his collar bone. He blamed the downtube shifters for the fall.
    Being a cruel parent I have brought my kids up in great hardship so the lad has an old racer with downtube shifters, although they are indexed. He's also learned to drive in a car that only has 4 gears and you need to pull the choke to start it. As a result of my cruelty he has actually gained a bit of mechanical sympathy and can nurse something that isn't working perfectly.
  • Vino'sGhost
    Vino'sGhost Posts: 4,129
    Svetty wrote:
    If you aren't sure what you are doing maybe best take it to your LBS?
    LOL in case the saturday boy knows what to do with something the age of his grandparents LOLOL
  • Vino'sGhost
    Vino'sGhost Posts: 4,129
    keef66 wrote:
    Veronese68 wrote:
    I can see why these type of shifter are referred to as 'suicide levers'
    I always thought suicide levers were the extra brake levers that were utterly rubbish and barely slowed you down. Like these:

    Me too. They were indeed utterly rubbish.

    Maybe the yoof wot have only ever known STI type shifters think faffing around with shifters on the downtube is suicidal? Whereas old codgers like me grew up with them and could select any gear precisely and without really thinking about it.

    If so, how do the millennials cope with extracting a bottle on the move or fishing something out of a jersey pocket?
    its ok they feel safe because they have a helmet and a zillion watt flashing led