Worn chainring? DA7900 53T 2000km

Ben6899
Ben6899 Posts: 9,686
edited January 2015 in Workshop
Hello,

Does anyone think this chainring looks slightly worn?

It's a DA7900 with 2000km, nice weather, use. It's only seen one chain - same kilometerage and less than 1/16 worn. I noticed the possible issue while just checking the chain.

I first thought "that looks like shark-finning", but on inspection of Google images it seems DA teeth are profiled toward that kind of shape from new (compared to a symmetrical Campagnolo chainring tooth).

Am I being paranoid? If not, then what on earth is the reason for such wear on a well-maintained bike!?

Cheers
Ben

(PS. it rides / shifts fine)

20150112_190300_zpsnrg0gspf.jpg

20150112_190341_zpsg1xoks7x.jpg
Ben

Bikes: Donhou DSS4 Custom | Condor Italia RC | Gios Megalite | Dolan Preffisio | Giant Bowery '76
Instagram: https://www.instagram.com/ben_h_ppcc/
Flickr: https://www.flickr.com/photos/143173475@N05/

Comments

  • mamba80
    mamba80 Posts: 5,032
    looks exactly the same as mine DA7900 - so unless we ve both got wrecked chain rings....... you FD is set higher than mine though :)
  • crankycrank
    crankycrank Posts: 1,830
    Looks perfectly fine. Shimano chainring teeth are machined with so many various shapes they look like they've been used for splitting rocks even when new .
  • mallorcajeff
    mallorcajeff Posts: 1,489
    Ive got a spare one thats done 200 ish miles and looks almost the same so its how they are. Ive also another one which has done 28k miles and not worn out
  • Ben6899
    Ben6899 Posts: 9,686
    Thanks chaps. I'm aware that some Shimano teeth look broken - caught out by that when I was a noob! - but I just thought I could see some "shark-finning" on the 'normal' teeth - which would have been sh1te on a 2000km-old chainring.

    Glad you could reassure me.

    On a related note, I do need some better lube though - I'm finding Finish Line Wet too heavy and Finish Line Dry too light. Any suggestions?
    Ben

    Bikes: Donhou DSS4 Custom | Condor Italia RC | Gios Megalite | Dolan Preffisio | Giant Bowery '76
    Instagram: https://www.instagram.com/ben_h_ppcc/
    Flickr: https://www.flickr.com/photos/143173475@N05/
  • mamba80
    mamba80 Posts: 5,032
    fwiw I use 0-5w synthetic car engine oil, its thin and very sticky, apply and wipe off excess with a rag, 1 liter will last you many years.
  • keef66
    keef66 Posts: 13,123
    After years of experimenting with bike specific lubes of the wet / dry / wax kind, along with various other motor oils and transmission fluids I now use plain old 3-in-1 oil. Big bottle for 99p from Wilkos. Drop on each roller, spin the cranks to work it in, then thoroughly wipe off the excess along with any muck it's displaced.

    It seems to be just the right consistency for a year round chain lube.

    Wet lube is too sticky and attracts / retains too much dirt. Motor oils are similarly dirt magnets. Wax lubes are OK in a dry summer; I like the fact that it flakes off taking dirt with it, but they are hopeless in the wet.
  • Ben6899 wrote:
    Thanks chaps. I'm aware that some Shimano teeth look broken - caught out by that when I was a noob! - but I just thought I could see some "shark-finning" on the 'normal' teeth - which would have been sh1te on a 2000km-old chainring.

    Glad you could reassure me.

    On a related note, I do need some better lube though - I'm finding Finish Line Wet too heavy and Finish Line Dry too light. Any suggestions?

    Finish Line Moist?