Shimano Cassette/Campy 9sp Felix Wong

[Note: this is just one way to get a pre-2001 9-speed Campagnolo shifting system to work with a 9-speed Shimano cassette. There are other—perhaps better—solutions now including using a JTek Shiftmate or using a post-2001 9-speed Campy shifter cog (in the Ergopower lever) in conjuction with a pre-2001 Campy rear derailleur. See this excellent in-depth article by the UK’s National Cyclist Organization for more info.]

In ’99, I made the switch to a Campagnolo shifting system (Ergopower levers, crank, derailleurs, etc.), but wanted to retain my wheels with Shimano hubs. There were two reasons for this: (1) wheels are somewhat expensive ($200 for my set of Mavic CXP33 rims and Ultegra hubs), and (2) Campagnolo cassette freehubs are LOUD! This is one area where it is my opinion that Shimano has the edge: while coasting, my Ultegra hubs are virtually inaudible.

Fortunately, the spacing between a Shimano and Campagnolo 9-speed cassettes are similar enough that they can be adapted. In fact, according to some USENET newsgroup cycling enthusiasts, a Shimano 9-speed cassette can be used as is with Campagnolo components without any modifications whatsoever, as long as the narrower Shimano chain is used. However, perhaps because I was using a Sachs chain, shifting did not seem to be perfect, so I decided to modify the spacing of the Shimano cassette to make it more similar to Campagnolo’s.

The spacing between the largest 5 cogs in both Shimano and Campagnolo cassettes is 2.5mm. However, the spacing between the smallest 4 cogs in Shimano’s is 2.5mm, whereas it is 2.8mm in Campagnolo’s. Hence, the trick is to increase the 2.5mm spacing between the smallest 4 Shimano cogs to 2.8mm.

I easily achieved this by cutting shims out of an aluminum can. Two shims add the required .3mm! Since there are 3 gaps between the 4 cogs that need to be 2.8mm, however, 6 of these shims are needed. I actually only used 5–just 1 between the smallest 2 cogs–and can report near-flawless shifting. Using 6 shims makes it difficult to install the cassette lockring. I also discarded the “built-in” shim/washer on the Shimano lockring.

See below for a step-by-step pictorial.

Cutting an aluminum can for the shim material.

Resultant aluminum sheet after cutting.

Tracing an outline of the shims using an existing spacer.

The resultant shims.

Installing the shims.

Discarding the pre-existing shim
on the lockring, and then
installing the lockring.

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One comment on Shimano Cassette/Campy 9sp

  1. Comment by Mark

    We are now several years down the road, any longterm observations?

    I have made the mod and I am going to try it right now, I was having trouble with auto downshifting which I had been told was because of the straight Shimano cassette/chain with the Campy Ergopower/der setup.

    We shall see.

    Interesting site and articles.


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