Shimano 100GS rear derailleur replacement

[John Sperr]

I have an old TREK 800 Antelope (ATB bike) that recently lost the rear
derailleur. It's a Shimano 100GS Series, Part Number RD-M100-GS working
on a 7 speed hub.

Does anyone know where I might locate a replacement or what part would
be a compatible substitute with the Shimano "Total Integration" click
shifters?

Thank you.

John Sperr
Rhinebeck NY

[Werehatrack]

Post by John Sperr
I have an old TREK 800 Antelope (ATB bike) that recently lost the rear
derailleur. It's a Shimano 100GS Series, Part Number RD-M100-GS working
on a 7 speed hub.
Does anyone know where I might locate a replacement or what part would
be a compatible substitute with the Shimano "Total Integration" click
shifters?

Any recent Shimano rear der, and any SRAM rear der marked as
"SIS-compatible", with either the same cage length or greater, using
the same type of mount (which I believe is an axle tab for the Trek
800), should work. Rear derailleurs don't care how many sprockets are
on the freewheel; the shifter takes care of moving the der the correct
amount to match up with the freewheel spacing.

Many bike shops have a junk box full of used serviceable units of this
type that can be had cheap.

If an axle-tab mount was present as original equipment and you want to
increase the range of options, a dropout-mounted der can be used with
the addition of an adaptor.