Originally Posted by
SoreFeet
I have a beautiful cyclone derailleur. I think it is 70's vintage. What is the the teeth capacity? How do I tell if it is the original or MK2...I think I would like to use it since the weight and condition is so great.
Look at the back of the parallelogram cage and you should see an inscription reading "MAEDA INDUSTRIES, LTD ... JAPAN" - or some such. There should also be two small mysterious upper case letters - which would be the date code for year and month. Let us know if you find this.
Photos would be useful for identifying the exact model ...