Jerry Moos wrote: "...I'm interested in the six-hole 116 BCD Randonneur rings, and hope to learn a bit more from this thread. You seem to be saying these were designed as a middle/inner ring which attached to the outer ring of a TA Cyclotourist crank...." --------------
Yes Jerry, the 5-pin Randonneur outer chainrings were just a different drilling the rings used on a 5-pin (ref.710) crank arm. (Basically, if you're eyeballing a 52 tooth outer ring the drilling would appear to be right about at the center of the arms).
----------------- JM: "...I had been guessing instead that the Randonneur rings were first used with the three-arm cottered steel 116 BCD cranks made by very many manufacturers. I had about concluded that three holes of the Randonneur were used to attach to the crank, while the remaining three were used to attach a three-hole 116 BCD inner ring like the TA Professional...." ------------------------
You had lost me here, Jerry. The TA 3-pin Professional set which I have (circa 1975) has only 3 holes on both inner and outer rings. And, they bolt together with 3 simple bolts passing through the crank arm spider (just like Campy, etc)...
BUT, just now Jerry, I've finally found more info. ~ In the 1963 Ron Kitching catalog (page 10), there is shown two different configurations for "Type Randonneur Chainwheels."
For the Randonneur 3-arm double (ref 2213) or the triple (ref 3213), the outer chainring (ref.RA203) is drilled with 6 holes for connecting the chainrings and this ALSO has 3 ADDITIONAL tabs extending between three of the windows, for attaching separately to 3 arm cranks (which TA did not yet produce themselves).
This page also shows the rings for the standard 5-pin cranks (which TA actually was also making by then). These sets were the Randonneur 5-pin Double (ref.2215) and the 5-pin Triple (ref.3215). That outer chainring was (ref.RA205)
The TA inner chainring used for BOTH the 3-pin and 5-pin Randonneur set-ups was the same (ref.206).
------------------- JM: "... One reason I thought this is that most of the few Randonneur rings I have seen are 48T to 52t, i.e. an outer ring, while I have seen lots of three hole rings in 42T, 40T or 38T...." -------------------
Yesterday I got an interesting email from Mike Barry in Toronto [Bicycle Specialites]
He said:
1. I was about the only person who has even mentioned these rings in all the 35 years he has been dealing with TA.
2.) He knew just what I was talking about and actually had a couple of the inner rings - but just in 39 and 48 teeth.
[ It struck me odd that there even would be a 48t inner ring ]
----------------- JM: "...Anyone know for sure which applications the Randonneur rings were first designed for? Regards, Jerry Moos Big Spring, TX " ---------------------
Which came first; a very interesting question.
TA's 5-pin configuration chainrings were being manufactured by them since maybe 1950, and it would be easy to re-drill the outer rings,... but why bother when the 80 BCD already had this covered.
TA's choice of using specifically the 116 BCD - which is exactly the diameter same as the arms on common 3-arm cranks - would seem to imply that originally they intended those cranks to receive the Randonneur rings. However, their outer rings for the 3-arm cranks were unique forgings with 3 additional mounting hole tabs... although they already did make a single road chainring for the 3-arm cranks - with just 3 holes drilled, and down to a 36 tooth ring.
With that drilling TA would actually be able to use THE SAME inner rings on both style of cranks... They could still use their basic 5-pin outer ring forgings for various patterns by just making an alternate drilling on the outer rings.
The consumer could transfer over some of the components over if they upgraded cranks. And maybe this was a selling point to help TA hit a broader market... cheaply. So perhaps this was the true reason they thought to produce the chainrings in the first place.
So, which was the first use? My guess would be neither. But now I'd REALLY love to see some of their early catalogues from the 50s to follow an actual chronological development of their products!
Bob Hanson, Albuquerque, New Mexico, USA