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PostPosted: Wed Nov 06, 2013 9:39 pm 
rBoTM Winner
rBoTM Winner

Joined: Fri May 20, 2011 5:59 pm
Posts: 641
Location: West Yorkshire
FINNEY1973 wrote:
Velobase confuses me when it comes to 1990 - 1994ish 8 speed mechs - ties in with the Index technology but it describes them as friction derailleurs? Surely if they are part of the 'group' then the Record & Chorus mechs must be index?


Technically it's the shifters/ergos that are indexed not the mechs. While Shimano designed their whole groups to work with indexing, Campagnolo tried to make everything back compatible and it didn't really work.


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PostPosted: Wed Nov 06, 2013 9:50 pm 
Retro Guru

Joined: Tue Oct 16, 2012 4:16 pm
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Location: NOTTINGHAM
gavr wrote:
and it didn't really work.


and never was a truer sentence written..... :D


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PostPosted: Wed Nov 06, 2013 9:53 pm 
rBoTM Winner
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Joined: Tue Apr 25, 2006 12:06 pm
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Location: Vienna, Austria
gavr wrote:
FINNEY1973 wrote:

Any finally to the DT internals - see attached - to my eyes it doesn't match any of the colour coded inserts so 8-speed??


Most certainly 8 speed.

I think you need a newer rear mech but even they can be tricky


Now this is getting tricky.

Firstly,if your rear mech looks like the one below then it's definitely 8-speed compatible, no question about it.

Image

Not wishing to state the obvious but I've got a feeling the issue lies within the iincompatibility between your 8-sp cassette and your 8sp DT shifters. The A/B rear mech ran from 88-92 and your SL-01RE CG Record DT shifters ran from 92-94 which tells us that they were never really designed to work together. Now, why would one 8-speed system be different to the next? Well, Campagnolo did in fact have three Syncro systems, Syncro I, Syncro II and Syncro 8sp, your DT shifters are Syncro 8sp. Syncro 8sp came out in 92 at the same time as Ergo levers but it was the first time Campagnolo made kit that wasn't backwards compatible with older potentially similar kit. I suspect the brief was to make revised DT syncro shifters that worked with the new Ergo-specific rear mechs. I know the center-to-center cog spacing required for the the post-82 DT shifters (Synro 8sp) is 5.0mm, I fear your cassette maybe different. In which case my suggestion would be to either change the shifters to Syncro I or II or update the cassette, your lovely A/B rear mech should work with either.

How does this sound?


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PostPosted: Wed Nov 06, 2013 10:17 pm 
rBoTM Winner
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agentorange wrote:

Now this is getting tricky.

Firstly,if your rear mech looks like the one below then it's definitely 8-speed compatible, no question about it.


I think we're agreed that technically it's supposed to be eight speed compatible, it's actually getting it to work that's the problem


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PostPosted: Wed Nov 06, 2013 10:25 pm 
rBoTM Winner
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gavr wrote:
agentorange wrote:

Now this is getting tricky.

Firstly,if your rear mech looks like the one below then it's definitely 8-speed compatible, no question about it.


I think we're agreed that technically it's supposed to be eight speed compatible, it's actually getting it to work that's the problem


OK true but what I'm suggesting is that it isn't the RM that's to blame. Your DT shifters shifts aren't placing the chain on the sprockets correctly so surely that suggests a compatibility issue between cassette and shifter.


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PostPosted: Wed Nov 06, 2013 10:33 pm 
Retro Guru

Joined: Tue Oct 16, 2012 4:16 pm
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That sounds more than plausible if indeed the brief at Campag was to make syncro 8sp that worked with a 'compatible' RM. For sure, I cannot disagree with anything in either your logic or knowledge on that one. So where does leave me - my RM is as per the picture - the DT levers are Syncro 8sp so the spacing - I understand the logic - correct spacing between cogs equates to the 'x' distance of equivalent cable pull through the shift on the levers. So my existing cassette is 8 speed and through some rather rudimentary calipers I've measured my spacers at 6mm (is this correct and standard for a Campag 8 speed?) and if 5mm is the optimum then can I not just buy new spacers and try that (or can I not get 5mm spacers easily) and why is my existing cassette fitted with 6mm?

Apologies for my ignorance - I just like building bikes and riding them (when they work!!!) :)


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PostPosted: Wed Nov 06, 2013 10:55 pm 
rBoTM Winner
rBoTM Winner

Joined: Fri May 20, 2011 5:59 pm
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Location: West Yorkshire
The spacing should be 5 mm centre to centre. Your cassette is part of the 8sp Record and Chorus groups - see the 1992 catalogue again - as are your shifters.

A can believe shifting might be very sensitive to any misalignment of the mech hanger if the bike's been dropped


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PostPosted: Wed Nov 06, 2013 11:04 pm 
Retro Guru

Joined: Tue Oct 16, 2012 4:16 pm
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Location: NOTTINGHAM
Frame is like new, barely a mark on it so it hasn't been abused - Got another cassette somewhere so i'll give that a go, going to put a friction shifter on and try that to see if I can get it operating smoothly and across the cassette without issue - by hook or by crook this will work to some level, whether I'm happy with that level is another matter but i'll cross that bridge at the weekend.


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PostPosted: Sat Nov 16, 2013 3:25 pm 
Retro Guru

Joined: Tue Oct 16, 2012 4:16 pm
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Location: NOTTINGHAM
3 hours this morning :facepalm: switched over to some friction only levers and it works fine - up and down the cogs without issue. So it's a compatibility problem with the syncro levers, cassette and the RM. I've had my beady eye on exactly what's not working and it's principally the click on the lever doesn't correspond to the correct amount of travel on the RM. So the symptoms: the chain isn't sitting quite central on many cogs, it's in gear as such but it's hitting (fractionally) the adjacent cog hence the noise. After watching what's happening in each gear and this off-centre chain issue I'm concluding that the RM (though capable of 8-speed and capable of 8-speed indexing) isn't happy with what i'm asking it to do. The chain line is perfectly straight through the RM and across to the chainrings.

So to the next step I could sit and get more frustrated and annoyed by this or buy a RM that's 1992 - 1994 (Chorus or Record) so that they are designed to work together. I could run it in friction mode but that's not what I want. This bike will be doing many a mile so it needs to right, my hunch is to go for another RM.

When PITA was mentioned earlier in the thread I thought how hard can it be! PITA is bang on the money I reckon!


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PostPosted: Mon Dec 30, 2013 6:50 pm 
Dirt Disciple

Joined: Sun Aug 25, 2013 7:54 pm
Posts: 27
Not meaning to resurrect an old thread, but this is great information. I have a 1989 Colnago Spiral Conic currently set up with Record 10 components, am occasionally tempted to backdate it with period correct C Record components...but then I reread this thread. :)


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