Originally Posted by
Lascauxcaveman
The other two choices are, pictured on the right, a slightly used Shimano Tourney MegaRange, nearly one pound of brobdingnagian engineering writ large in steel and plastic (What a bulletproof behemoth! And since these things come
new from various eBay sellers at around $15 - including shipping - I feel no compunction against listing its swap meet value at around $7) and on the left, the legendary Shimano RD-TY20 (which you've never heard of because it's just a junk derailleur that came on Wal*Mart bikes way back when Wal*Mart was just a corner drug store in some butthole backwater of Arkansas.) Swap meet value, maybe $1?
Right now, I'm leaning towards the RD-TY20, not only for the general rusty crappiness of the thing, but because it weights less and probably works just as well. Also, the RD-TY20 has a cage that's slightly bent inwards. Not yet ready to do the Dance-Of-Death-With-The Spokes, but close enough to keep things interesting.
Anyone want to offer their input?
The TY 20 is legendary when you consider it's origins... it goes way back to the 1960's when Shimano was copying the Simplex Model 61 and created the Skylark which turned out to be a derailleur that indexed quite reliably when the cable anchor's position was changed (last model).
The TY20 has also been copied and cloned by other makers and you really need a Falcon copy to really bring the level down... the TY20 is actually pretty decent.
It might be the most successful derailleur ever.