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 Post subject: Front mech adjustment
PostPosted: Wed Dec 26, 2012 1:31 pm 
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Location: Warks
small but silly stuff:
On my steelie with a band on front mech, I have to pretty much trim the front shift lever after each change at the block (14-28) this isn't the case with other steelies with friction shifters I have ridden, usually only needs a trim when you get to more 'extreme' positions...any clues?


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 Post subject:
PostPosted: Wed Dec 26, 2012 2:53 pm 
Old School Grand Master
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Location: Cumbria
Depends on how "thin" the slot is for the chain in the front mech.......early campag seemed quite narrow whilst simplex were a lot for forgiving. Some front mechs had a curved-in inner plate which "helped" the chain onto the big ring. Sometimes could be straightened which helped.

What are ou running?

Shaun


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 Post subject:
PostPosted: Wed Dec 26, 2012 3:18 pm 
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Hi it's a Campag record... cage does look narrow now you mention it...
also it doesn't seem parallel to chain ring, tail is further outboard so maybe I should swivel the mech to get that lined up ...


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front mech1.jpg
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 Post subject:
PostPosted: Wed Dec 26, 2012 5:33 pm 
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I always thought that was something that went with the territory... A 3/32 chain, 5/6 speed block... It's just the way it works. More cogs/narrower spacing and chain means you can shift a few more gears before it happens? I'm no authority.. I bought my last derailleur in about '85.. :shock:

Apart from what's already mentioned, two additional things which could be influential: a)Whether or not the chainrings run perfectly true. b)Length of chainstays.

P.S. The spacer between the cage-plates at the aft of the cage does look a bit weird (i.e. narrow) in that pic. The cage should be slightly wider at the aft than at the fore?


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 Post subject:
PostPosted: Wed Dec 26, 2012 6:12 pm 
Old School Grand Master
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The mech needs swivelling around a bit so it's parallel to the chainrings or slightly inboard at the rear.

Early Campag Record were notoriously narrow, I'll measure my spacer tomorrow but looks right to me.

Shaun


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 Post subject:
PostPosted: Wed Dec 26, 2012 7:07 pm 
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maybe I can insert a small bush and longer bolt at the rear of the cage... I check the rings also , many thanks

ps i have an old Bertin with friction shift, same 6 speed rear block and you'd think it was fitted with indexed, the gear shift is butter-smooth and hardly ever needs trimming... 8)


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 Post subject:
PostPosted: Wed Dec 26, 2012 8:11 pm 
rBoTM Winner
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I agree with Midlife, from the pic it looks like the mech needs twisting into line as it is not parallel to the chain ring.


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 Post subject:
PostPosted: Wed Dec 26, 2012 8:13 pm 
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thanks guys :)


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 Post subject:
PostPosted: Wed Dec 26, 2012 8:47 pm 
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Campag stuff has always been noisy.........in the 70's there was a right racket when the group (peloton) came to a hil or set themselves up for a sprint........

Suntour realy should have cleaned up when it came out but sadly left it to Shimano.

Shaun


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 Post subject:
PostPosted: Wed Dec 26, 2012 9:43 pm 
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Quote:
Early Campag Record were notoriously narrow


Fair enough.. that's before my time! The only reference I have to hand is a mid 80s Nuovo Gransport. Distance between insides of cage plates: Fore.. 10mm. Aft.. (widest part, just before the outer plate bends in to meet the spacer).. 12mm. The spacer itself is about 8mm.

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ps i have an old Bertin with friction shift,


Is it the same model of front changer?.. and how long are the chainstays, compared to this bike?


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