Re: [CR]right chain size for cambio corsa?

(Example: Bike Shops)

Date: Sat, 07 Apr 2007 23:17:36 +0200
From: "Martin Appel" <martin@team-ware.de>
Organization: RC Concordia 86 =?windows-1252?Q?M=FCnchen?=
To: The Maaslands <TheMaaslands@comcast.net>
Subject: Re: [CR]right chain size for cambio corsa?
References: <045f01c7793c$16379ad0$0200a8c0@HPLAPTOP>
In-Reply-To: <045f01c7793c$16379ad0$0200a8c0@HPLAPTOP>
cc: CR <Classicrendezvous@bikelist.org>

Thanks to all who replied both on and off-list!

many thanks to Aldo too for your advice. In fact, the cluster "tumbles" a bit while freewheeling, but as i've seen that from other clusters of all vintages, even new ones, i dont think it does any harm. I'll check the chainwheel for roundness!
> Firstly, the bike is most definitely not from 1940, but rather from the
> end of the 40's or perhaps even more likely from the early 50's. Check
> the hub locknuts and perhaps the BB axle and headset for date codes.

You are right, hub nuts say 49. Seller told me the QRs werent original and equipped me with a new set of longer pins (maybe he only meant the pins werent original? we had lost the bilingual skills of his daughter at that part of the conversation), only i forgot to ask how to replace them. are they threaded?
> Secondly, most cambio corsa bikes with 4 block freewheels work best with
> 1/8" chains as they are stiffer and make the shifts more precise. You
> must however be aware that many 'newer' freewheels don't like the wider
> chains much, so the problem may lie here. As Aldo correctly pointed out
> it could also be a problem with the height of the shifter 'cage'.
> Sheldon is all wet on this as 4 blocks were commonly available in Italy
> in the late 30's and five blocks in the late 40's.

my 4 block is an Everest, and there is pretty much room, i guess a 5 block would fit without problems. How do i determine whether the block is 1/8 or 3/32? do the sprockets have a characteristic width or spacing? the 1/8 chain ran nice and silently on them on the workstand.

The cambio corsa
> dropouts were however not very amenable to use with a 5 block. Have you
> verified that you do indeed have the 17 or 19 tooth dropouts?

they are 17 tooth type.
> It is furthermore my experience that many of the problems that occur
> with cambio corsa and Paris-Roubaix derailleurs are linked to incorrect
> gap between the top and bottom sides of the drop-outs. Over the years
> many have been spread open which makes shifting almost impossible. The
> same can also happen if the gap is not constant.

the gaps are looking nice and parallel to me. the axle needs a bit of force to be pushed in when mounting the wheel, but i applied some grease and now it is what i would call a nice tight fit.

You must also check out
> Aldo's incredible video clips showing how the gear 'can' shift when used
> by somebody with dexterity and a properly set up bike.

watched it and gasped in awe :) i'll need to take up gymnastics to be able to reach down as far effortlessly :)

Martin Appel Munich, Germany

--- *looking for "Automoto" fork crown medals! please send mail :)

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