Could a duff chain sharkfin my chainring?

Hitby
Hitby Posts: 218
edited October 2009 in MTB workshop & tech
Hi all, I've just fitted a Deore groupset that I bought and went out for my first ride today - unfortunately the chain (shimano HG-53) snapped twice within about 3 miles - luckily for me I ran across a couple of fellas that gave me some powerlinks otherwise I'd have been screwed.

Anyway, there's obviously something wrong with the chain but as I've just been fitting another new one I've noticed that some teeth on the chainring are shark finned already, this was a completely new groupset less than 5 miles ago!

Could the duff chain have caused this or is the chainring faulty as well? Either way I want replacements from Merlin but I'd appreciate the advice of someone with more experience,

3976266345_9e3e8dbb6e_b.jpg

Thanks for your help

Comments

  • supersonic
    supersonic Posts: 82,708
    Looks ok to me. Worn chainrings look far worse than that.

    Get a SRAM chain ;-)
  • Hitby
    Hitby Posts: 218
    So do you think the hooked teeth are normal and nothing to worry about (bearing in mind it's only done 5 miles)?

    http://skitch.com/wddn/nbshj/dsc-3728.j ... otal-pages

    If so, I'll just leave it on the bike and just get them to replace the chain but I don't want to ride on it if it's going to cause more problems in the long run. The guys that helped on me on the trail said that it didn't look right

    edit: oh and I bought a PC-971 from the lbs ;) seems much better quality
  • supersonic
    supersonic Posts: 82,708
    I don't see any hooked teeth!

    These are worn teeth:

    chain_ring_wear_02.jpg

    Shimano chainrings and teeth are multi profiled and are different in various parts of the chainrings. This is to aid shifting.

    It can be seen here on this new chainring from SHimano:

    704908Lrg.jpg

    Relax, refit, and riiiiiiiiiide!

    ;-)
  • Hitby
    Hitby Posts: 218
    well, Merlin Cycles said chains don't come with warranties (even when they snap within 3 miles!).

    I've learnt my lesson though, I won't be ordering anything else from there. The extra cost at the LBS is worth it.
  • Agreed; those teeth look fine. They even have paint on them. I am not quite sure how it's possible to erode the hardened steel teeth without first removing the paint from them :?

    And yes - get a SRAM chain. It's perfectly compatible with your groupset and you don't need anymore of those silly shimano pins.
  • lesz42
    lesz42 Posts: 690
    Hitby wrote:
    well, Merlin Cycles said chains don't come with warranties (even when they snap within 3 miles!).

    I've learnt my lesson though, I won't be ordering anything else from there. The extra cost at the LBS is worth it.


    er? so you rather pay more for the same thing?
    Giant Trance X0 (08) Reverb, Hope Hoops 5.1D, XT brakes, RQ BC, Works Components headset 1.5
  • Hitby
    Hitby Posts: 218
    And get some form of face to face service when something goes wrong? Absolutely!
  • lesz42
    lesz42 Posts: 690
    well, wait untill your lbs is wrong or something, mine told me that 17 mm cone spanners are rare, and even he does not have one in the workshop!


    and he was charging £15 each for a 15 mm one, got 2 , one 15mm one very "rare" 17mm for £3 each, from the net


    god i am so lucky to get a "rare" 17mm cone spanner :roll:


    and wanting to charge £40 to set up my rear mech, as it takes all day? did it my self in an hour ( first time go at it too)



    i went from a shimano chain, when it got a bit worn to kmc or sram, just from reading reviews moaning about shimano "pins"


    my merlin built wheels are great, again my local lbs were charging almost £100 more for the same spec, worth it?



    no



    and to show that i am fair, he rebuilt my rear wheel, had about 5 new spokes, and a buckle of about 4/5mm

    charge for spokes and true? £7


    amazing price and service


    but i am still aware that the 2 local lbs's can have bad customer service ( the other one tried to sell me a shimano chainset, and told me the BB was an extra £30)


    best thing is to read and learn and ask questions here and else where, and do it your self
    Giant Trance X0 (08) Reverb, Hope Hoops 5.1D, XT brakes, RQ BC, Works Components headset 1.5