Raleigh/Carlton Grand Prix: Setting Rear Derailleur [Huret Challenger '70s + other vintage mechs]

Setting up the rear derailleur is essential if you've fitted a new one or replaced your free-wheel. I fitted a freewheel with slightly smaller ratios and a new rear wheel which may have had slightly different spacing and found that I could no longer select the largest cog, while selecting the smallest cog would easily throw the chain off.

The Challenger, like all French-made Huret mechs and a lot of other vintage derailleurs, are simple in design and do not require a lot to set up. Online guides show modern and more complex mechs with functions that vintage ones lack.

1. Loosen the nut holding the gear cable at the rear derailleur and allow the cable to slacken. [It is likely a small bolt with a hole that the cable runs through and the nut holds the cable in position.]

2. Press the gear-lever fully forward, parallel to the cross-bar so the cable is in its full loose position.

3. Set the chain at the smallest / outermost cog on the freewheel.

4. Set the outer-limit of the derailleur's movement by adjusting the H-screw until the upper jockey-wheel is in line with the smallest cog of the freewheel. [This is the foremost of the two small screws located on the side of the derailleur itself.]

5. Pull the gear cable tight and tighten the nut holding it in place at the rear derailleur.

6. Pedal forward and draw the gear-lever up until the largest cog of the freewheel is comfortably selected. [The inner-limit screw on the mech may prevent this and will need adjusting first.]

7. Set the inner-limit screw [or B-screw] on the derailleur to prevent it going any further than the largest cog. [This is the left-hand screw located to the rear on the derailleur.]