Re: [CR]9mm chainring bolts for Campy Sport 3-arm

(Example: Bike Shops:R.E.W. Reynolds)

From: "Olof Stroh" <>
To: "Aldo Ross" <>, <>
References: <001001c62bf1$1eab18c0$0617fbd1@Newhouse>
Subject: Re: [CR]9mm chainring bolts for Campy Sport 3-arm
Date: Tue, 7 Feb 2006 15:47:54 +0100
cc: EricMeddaugh@AirgoNetworks.Com

Aldo Ross wrote:

> Are the crank arms aluminum or steel? They were available both ways,
> steel earlier and aluminum later. On my '78 Competition G.S. they were
> aluminum, so I'm guessing your's are, too.
> The 3-arm "Sport" chainset used hex head bolts, rather than the socket
> head bolts, to attach the chainrings to the crank spider. Part numbers
> are 3325 "Sport chainwheel fastening screw" and 3329 "collar nut".
> Looks like the kind of bolt used on Italian 3-armed cottered chainsets
> from Gnutti, Magistroni, etc, but on these the arms are threaded so
> don't require the collared nut.
> In my experience the bolts in the 3-arm aluminum cranks often came loose
> and fell out - I used to tighten them after every ride. Replacement
> bolts were hard to find even back in the '80s... some folks gave-up on
> finding the correct parts, and drilled them to accept regular chainring
> bolts.
> Interestingly, the bolts connecting the chainrings are considered
> "fixed" and no replacement parts numbers are listed in the Campy
> catalog. The chainring description includes the text "Please specify
> the number of teeth of the fixed double chainrings".
> Perhaps the best hope is to find a shop with an 70's/80's-era Campy
> parts cabinet. I'll check I-Pro up in Bellbrook next time I'm there. _________ Some five-six years ago I got three sets of 3-pin Gran Sport cranks with chainswheels for a good price at a bike-shop. Worthless old junk, you know.

One 170mm with those 9mm hex nuts and two 150mm with "normal" Campagnolo bolts.

I admit to having the 9mm bored up to 10mm. It´s now a user (albeit on a nice Crescent owned by my daughter).

I´ve heard about the 150mms called "Baby Sport". Maybe the big one is just a "Sport"?

just complicating things

Olof Stroh
Uppsala Sweden