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Technical Help

We sell the tens of thousands of spares!

Finding the right spares can be hard and we are here to help. We are making a series of short videos that will show you how to locate the elusive spare part that you have been asking about on BikeRadar, Cycling Weekly or Mtbr.


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Questions and Answers

Shimano Long Cage and Short Cage Derailleur (SS/GS/SGS)

Understanding all the codes for Shimano is difficult even for us working in the industry. Here are some tips on how to understand the differences between short cage derailleurs and long cage derailleurs.

Essentially Shimano rear derailleurs come in different sizes to accommodate the size of the rear cassette: short cage or long cage.

The last 2 or 3 letters in the Shimano model number will indicate the cage length of the derailleur.

For example, a Dura-Ace rear derailleur code is: RD-7900. It will be followed by the letters SS if it is a short cage or GS if it is long cage model. The full model number would then be: RD-7900-SS (gear ratio compatible up to 30T) or RD-7900-GS (wide gear ratio compatible up to 32T).

This is the same for all the Shimano road type rear derailleurs; they all either end with SS or GS.

For Shimano MTB rear derailleurs, the last letters will be GS if it is short or medium cage or SGS if it is long cage. There are exceptions though, as you might get a Saint derailleur in a short cage.

An XT rear derailleur will be RD-M771-GS (medium cage) or RD-M771-SGS (long cage).


More Help Coming Soon

Please note we are often very busy in our shop so, where possible, when calling, please have the part number to hand.


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