[david james]

i understand colwood wheelworks of hailsham, east sussex are having remanufactured various sa toggle rods including the 4 speed (01323 848667) , has anyone successfully matched a modern sa 5 speed gearchange lever with an old style 4 speed hub?

[Bruce]

the ‘modern’ five speed hub controls vary significantly from one another and I do not think that the cable pull lengths of any of them will suit an FW four-speed. Specifically you need a long 1-2 pull and a long 3-4 pull on a 4s hub, and this doesn’t match any 5s single toggle shifter.

The all plastic trigger for the ‘sprinter’ 5s hub will only work with (either ball-locking or dog locking) sprinter hubs as well as post 2000 SRF5 and X-RD5 hubs without the (W) suffix. This trigger is still made and sold as a Brompton part.

An almost identical trigger exists for controlling the (W) suffix hubs which use a different (shorter on 1-2 and 4-5) cable pull. These triggers are usually marked (W) and the numbers on the top bezel are noticeably closer together than on the sprinter version.

The aluminium thumbshifter SLS50 is only suitable for the (W) hub. This shifter exists in two forms;
1) original
2) revised

SA have not given the revised part a new part number but you can tell which you have because the revised version has a dot on the bezel which the earlier version lacks. The revised version has less sticking friction between gears, so (in theory) doesn’t hang between gears following a downshift, which the earlier version did. Personally I don’t think they have fixed it. I’ve seen a lot of broken (W) hubs and I think the shifters are to blame. If you downshift there will be an overshoot, so you must manually pull the trigger back to the detent position for that gear, else risk slippage.

If you want a more contemporary look and more gears, I recommend converting the 4s gear to a 3s (using AW internals) or 5s (using AW toggle and key, revised large sunpinion locking dogs, additional left side pushrod) and then using SLS30 thumbshifters for control. The downshift overshoot is less important with the SLS30 shifter because it cannot make the gears slip badly in the same way as in the single toggle 5s hubs.

cheers

[david james]

thanks for that

[Author]

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