replacing rear mech and crankset

bing gordon
bing gordon Posts: 662
edited August 2009 in Workshop
ive a specialized allez triple 07 24 gear/8 spd and the rear mech is has a "Shimano Tiagra, long cage" on it at the mo so im wondering what would be a 1/2 decent replacement ? , any links would be handy.

its just there's so many rear mechs on the market and i wouldnt know a good one from a bad one. sometimes paying through the nose doesnt mean you get the best and im on a tight budget.

also , the sora triple crankset is looking worse for wear teeth wise so an replacement might be needed so any advise on that.
i do remember changing the crank on me mountain bike and it was a nightmare finding the right profile to fit due to all the different profiles heights on the crank.


  • keef66
    keef66 Posts: 13,123
    edited July 2009
    Is the rear mech knackered because of an accident? If it's just not shifting well it could just need lubricating, or it might need new cables, or the shifter could be at fault.

    If it does need replacing it would be simplest to go with Shimano, and if you stick with the triple chainrings you need the long cage mech. That should limit your choice a bit. Current Shimano rage from "cheap" to expensive is Sora, Tiagra, 105, Ultegra, Dura-Ace.

    Re the chainrings: are you sure they are worn? When new they have differently profiled teeth to help with shifting from one chainring to another.
  • skyd0g
    skyd0g Posts: 2,540
    As keef66 says above, and as you say you're on a tight budget - before you go replacing anything, a bit of fettling and TLC will probably get all running sweetly. :D
    Cycling weakly
  • maddog 2
    maddog 2 Posts: 8,114
    Tiagra is okay but 105 and Ultegra are better, so you pays yer money basically. Any Shimano 9spd long cage road mech will be fine. 10spd may work too but might rub on your fatter 8spd chain so I can't confirm this.

    as for cranks, you can either replace the rings or the whole chainset. The latter may well be cheaper, and you can upgrade too.

    See Ribble, ChainrEaction etc. for a start point on pricing and check your chain for stretch as that may be goosed too. No point in fitting new rings then running a shot chain on it, as you'll wear the teeth prematurely.
    Facts are meaningless, you can use facts to prove anything that's remotely true! - Homer
  • bing gordon
    bing gordon Posts: 662
    thanks for all the advise , i think i'll stick to what i got and try my best to tweek it all up after what you have all said , i just didnt relise how dear rear mechs can be.
    the rear mech is shitted up and abit groggy when shifting so i'll try to clean it all up and lube it before i replace the cables and chain.npo doubt i'll be dropping it off at my LBS monday !!.
  • keef66
    keef66 Posts: 13,123
    Have a look on the Park Tools website. Step by step instructions for sorting everything. Also Google for Sheldon Brown; again advice so simple even I can follow it. YouTube also has videos of people fixing bikes which is often easier to understand than words and pictures.
  • pinno
    pinno Posts: 51,786
    All for sale by me on e-bay ending tonight - look for "susofreality"
    seanoconn - gruagach craic!