I’m just returning to road cycling after a 9 yr hiatus from a bad knee and wanted to build a road bike using some old parts I had around . First I had on hand some 10 spd Campagnolo veloce Ultra shift shifters and I also had some Shimano spaced wheels which led me to look at the “shimergo” option to see if there were any new ideas on how to marry these disparate parts.
I’m no stranger to this, having once tried Campy 9spd shifters & der with a Shimano 9 spd cassette but the results were less than stellar, despite what others said so I was weary of half baked solutions again -like the supposed use of Sram 10 spd der or unconventional cable clamping.
Of course there is the J-tek solution or the shimano-cassettes-with-campy-spacings but my ideal solution was cheap, used of the shelf components and elegant (I never quite liked the idea of the j-tek thingy hanging of my derailleur or the hubbub kludge).
My “promised-land” solution is Campy shifters (cheap, light, reliable & ergonomic), a Shimano derailleur (cheap, light & reliable) paired with any Shimano spaced cassette which are cheap and have the best ratio options.
My first idea.
Many years ago, a Japanese seller on Ebay was selling something called the “magical pulley” (or at least that’s what I remember) which changed out the Campy lever internal pulley around which the gear cable wrapped to one of a different diameter which altered the cable pull but they were about $50 shipped. I toyed with buying a new campy pulley and dremelling it down to change the pull ratio but never did so.
Some details of the “magical” or “growtac equal pulley” being installed is here…
Confusion about Campagnolo linear vs variable cable pull
I posted recently about the myth that Campy shifters do not pull at a consistent rate and based on my findings here
http://www.bikeforums.net/bicycle-me...able-pull.html
I found both Shimano & Campy levers pull in a non-linear manner. This important finding eliminates the idea that this can never be a successful marriage.
My Solution
I was browsing and came across these sites..
A guide to rear shifting | Cycling UK
https://en.wikibooks.org/wiki/Bicycl...ing_Dimensions
Art's Cyclery Blog » Science Behind the Magic | Drivetrain Compatibility
and I noticed an old-style Campy derailleur has an almost ideal pull ratio for matching new Campy 10 spd shifters to Shimano rear mechs but these are close on 15 years old so any old units would be clapped out by now and probably expensive anyway. Wouldn’t it be great, I thought, if there was another modern der with a pull ration of 1.4:1?
Well, as I re-read the blog.artscyclery.com I almost fell of my chair with excitement. You know the eager kid and the back of the classroom with his hand in the air, grunting to get attention so he can shout out the answer? Well, that’s how I felt as I read any Shimano 11 spd (or Tiagra 4700 10spd) rear derailleur has a pull ratio of 1.4:1 as that is the golden ratio required to enable a 10 spd campy lever to use all Shimano rear parts. And all the info was right there but no-one seems to have joined the dots and as far as I can tell, nobody has published anything on this combination.
And it gets better as this combination should also work with 9spd ie Campy 9spd shifters with Shimano 9 spd der and cassette although this I have not tried yet. It also means a Tiagra 4700 shifter “should” pull the same cable as a campy 10 spd shifter and they are basically interchangeable.
The attached table (copied from the wikibooks site) shows what works where I substituted “Shimano 11spd” for “Old campy”as they both have a 1.4 ratio.
As you can see, for 10 spd we a standard Shimano setup is designed for a 3.95 mm cog pitch and this hybrid is calculated to shift 3.97mm which is only 0.5% error. Also note 9spd wants 4.35mm and this gives an almost exact 4.36mm per shift so it should work perfectly also.
I’ve been running for a few weeks a Tiagra 4700 der with the Veloce ultra-shift shifters, Ultegra 12-25 cassette and KMC x93 chain. All shifts have been smooth, quiet and well, it just works as it should.
So in summary:
Any 10 spd Campag Shifter + any road Shimano 11 spd Derailleur (or Tiagra 4700 or microshift 11spd) + and any Shimano spaced 10 spd cassette
OR
Any new style 9 spd Campag Shifter + any road Shimano 11 spd Derailleur (or Tiagra 4700 or microshift 11spd) + and any Shimano spaced 9 spd cassette.
What this open up.
This opens up the ability to build nice cheap 10 spd training or commuting bikes.
Example : I found Veloce levers ($84 & 358 gram) plus Shimano 105 5800 der ($25 & 230 gm ) with any 10 spd cassette of your choice.
Compare this to a similar Chorus der ($200 & 186 gm) with a Centaur cassette ($70 & 248gm) –and that’s not to mention wheels where Shimano compatible hubs are way more common and cheaper than their Campy counterparts.
And, if you’re out touring on your campy 10 spd and the levers dies but the only option is Shimano, a Tiagra 4700 could be substituted to get you going.