​Instructions for setting up Sunrace 11-42t range expanding cassette with longer B screw

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Instructions for setting up Sunrace 11-42t cassette

A medium or long cage rear derailleur will be required for use with a 11-42t cassette. In most cases,

swapping the Sunrace 11-42 cassette for a standard ratio cassette should be a straightforwards

swap. However, in order to gain the clearance necessary for the rear derailleur, it may be necessary

to move the derailleur a little further away, by turning the ‘B screw’.

With the B screw turned to the correct point, the gap between the upper jockey wheel and the

bottom of the largest cog (the 42t) should be approximately 13mm (ignoring the chain). In rare

cases, the original B screw may not move the derailleur enough when it is fully screwed in – in this

case, it will need to be replaced by the longer B screw supplied with the cassette. This is a

straightforwards swap, the original B screw can just be unscrewed, and replaced with the longer one

provided by Cranknuts.com