Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: Mrs Pingu on 06 January, 2019, 06:08:25 pm

Title: Tiagra SL4600 shifter repairable?
Post by: Mrs Pingu on 06 January, 2019, 06:08:25 pm
Flat bar shifters, like these: https://www.chainreactioncycles.com/shimano-tiagra-4600-2x10sp-flat-bar-shifter-set/rp-prod145034?mx=a

Anyone know if they're repairable? Google hasn't helped much. The front shifter just stopped and went all floppy. It doesn't feel seized or jammed, more like a pingfuckit has broken or pinged off. I've bought a new set now but on the off chance that it might be reusable I thought I'd ask....
Title: Re: Tiagra SL4600 shifter repairable?
Post by: Torslanda on 06 January, 2019, 06:38:40 pm
Have you removed the cable? If the cable isn't engaged in the socket correctly it can jam the shifter.

The usual sketch is the grease solidifies and the pawls/ratchet mechanism won't engage. Remove the cable and keep squirting the WD40/TF2/GT85 in through the cable port whilst working the triggers. Rescued several sets of shifters using this method, suppose I'll never get rich...
Title: Re: Tiagra SL4600 shifter repairable?
Post by: Mrs Pingu on 06 January, 2019, 06:43:13 pm
Yeah I saw the WD40 method on YouTube. Didn't look like it felt like my lever but I can have a quick poke sometime.
Title: Re: Tiagra SL4600 shifter repairable?
Post by: Brucey on 06 January, 2019, 08:38:43 pm
typically if the left shifter manages the 1-2 shift and then goes all floppy, the upshift pawl has stuck.  WD40 or similar will usually free it off but some form of better lubrication will keep it good for longer.

You can usually remove a cover on the bottom of the shifter, and actually see the upshift pawl; this makes it easier to direct the WD40 correctly.  Obviously if you still have a mech connected (check the cable isn't binding and that the mech itself is free.....)  it should pull back at the workings so that it is easier to 'exercise' the shifter.

Occasionally a spring breaks inside an STI shifter but  IME a sticky pawl is far more common. If a shifter is to go sticky, it will almost invariably be a front triple shifter, simply because it is used so infrequently.

cheers