Worn chainring? DA7900 53T 2000km

Ben6899

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)

mamba80

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

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

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

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?

mamba80

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

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.

arthur_scrimshaw

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?