This reminds me - I found the answer to most of my questions about Deore chainrings in a scanned 1982 Shimano catalog on Sheldon's site. Believe it or not, there were, at least in 1982, FOUR different Deore outer chainrings. I'm guessing at the BCD's based on the range of available rings:
Model LD double. Inner ring 130 BCD, same as Dura Ace, and the least useful for wide range gearing. Unfortunately, this is the one I have,
Model MD double. Inner ring probably 110 BCD, smallest ring 33 or 34. Looks like in 1982 this model outer ring only went up to 50T.
Model LD triple. Middle ring 130 BCD. Inner probably 74 BCD. Smallest inner ring listed 28T, but maybe this was just for complete cranksets, as the MD triple below shows inner ring as low of 20T.
Model MD triple. Middle ring probably 110 BCD down to 33 or 34T. Inner probably 74 BCD down to 20T. Again, looks like the outer ring in 1982 only went up to 50T.
Deore seems to have emulated not only some of the French design, but also onfusing nature of French offerings.
So anyone have any of the last three Deore outer rings for sale?
Speaking of triples, there was some discussion a while back about the maximum or minimum tooth differential if the chain is to shift smoothly from the inner to middle ring. Was it the inner-middle spread, or the middle-outer spread that was said to be critical in this regard?
Regards,
Jerry Moos Houston, TX
MARK <mhoffman0@snet.net> wrote: I just "uneathed" a couple of Lotus bike from our shop dungeon, seeing as the Deore crank sets on them were a recent topic. One was a double and the other a triple. The triple was a mess, as were both bikes. The DD pedals seem seized and the crank bolts in the self-extractors were bending the allen keys. I'll see if the Kroil did any good over night.
But why I REALLY made this submission was the fact that I'm looking for a left mate to the crankset for my '53? Dawes, which I broke while test-riding it prior to purchase some 20 or so years ago. It seems like it fits the Allez description Steven was talking about. The bike did have Allez pedals.
I've posted some pics of both the above mentioned cranksets at
http://client.webshots.com/
Mark Hoffman New Britain, CT
And yes, Alan...I will call you today ;-)