Does this chainring need replacing?
#1
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Does this chainring need replacing?
Hi, My son has just bought a 2nd hand bike to use on a smart trainer. The cogs look a bit worn on the large front chainring. Will it need replacing soon?



#2
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Is the chain skipping? Every chain ring will need to be replaced eventually if it is used .... (as in, "put to use, ' not "purchased from a prior user,") so yes, in time, it will need replacement. I wouldn't replace a chain ring if it was still performing well, though. If the chain skips off or slips ... get a new right, right away.
Of course, I could be wrong.
Of course, I could be wrong.
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No. The teeth aren’t supposed to be the same all the way around. Some of the teeth will look flatter than the others but that is a design feature that improves shifting. Your chainring looks fairly fresh and serviceable.
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Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
#4
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Is the chain skipping? Every chain ring will need to be replaced eventually if it is used .... (as in, "put to use, ' not "purchased from a prior user,") so yes, in time, it will need replacement. I wouldn't replace a chain ring if it was still performing well, though. If the chain skips off or slips ... get a new right, right away.
Of course, I could be wrong.
Of course, I could be wrong.
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When I worked in bike stores, customers would come in to ask about/complain about the short teeth on the big ring at least a few times per week. We'd just walk them over to the display bikes and point out that the big rings on all the brand new bikes had teeth that looked exactly the same as their ring.
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tooth 'shape' is hard to judge on modern chainrings, some have flatten top, others have a sharkfin shape which appears 'worn' but isn't.
way we had checked BITD, with chainline tight on chainring and all the way through jockeywheels and middle cog - pull/lift chainlink off of chainring at the point where a horizontal line bisects the Bottom bracket. This is the point where the chainwrap on the ring is the tightest.
If the chain lifts so much that the chainring teeth are greatly/more than fully exposed - ring may be worn... Total Judgement call !!! I'm not acquainted with any 'hard measure'.

This one looks ok.
IMPORTANT Conidtions
Chain must be in almost new or new condition. Worn chains first thing to check (best with a Park Tools chain checker (there are many poor/cheap substitutes which aren't accurate).
The CC3 and similar from Park Tools are great.
Used Bike? Always check the chain before using...
My visual assessment (which may be wrong) is the chainring looks good.
Ride On
Yuri
way we had checked BITD, with chainline tight on chainring and all the way through jockeywheels and middle cog - pull/lift chainlink off of chainring at the point where a horizontal line bisects the Bottom bracket. This is the point where the chainwrap on the ring is the tightest.
If the chain lifts so much that the chainring teeth are greatly/more than fully exposed - ring may be worn... Total Judgement call !!! I'm not acquainted with any 'hard measure'.

This one looks ok.
IMPORTANT Conidtions
Chain must be in almost new or new condition. Worn chains first thing to check (best with a Park Tools chain checker (there are many poor/cheap substitutes which aren't accurate).
The CC3 and similar from Park Tools are great.
Used Bike? Always check the chain before using...
My visual assessment (which may be wrong) is the chainring looks good.
Ride On
Yuri
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Since you weren't referencing a set of Sora cranks/rings, the point you were attempting to make with your "side eye" remark is unclear.
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