Martin wrote:
"i recently aquired a cambio corsa bike. now i wonder what might be the best chain to use with it? I tried a standard inexpensive 1-1/8" chain since i figured that was the best match to the standard chain in 1940 (right?). On a testride i found the performance left to be desired, it basically teft me with only one gear of 4 to use. Would a 3/32" be a better fit?"
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. 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'.
In a subsequent post, Martin added:
"Side question: was a 4-speed cluster customary in 1940? Sheldon says they started to be around not before the 50ies?"
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. 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?
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. 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.
Steven Maasland
Moorestown, NJ
USA