BB, Chainring and Chain wear

Had 30 minutes to kill so attempted to do some 15s/45s sprints, sadly just starting the last set I snapped the chain with my gigantic power output (unlikely but I can dream).

This means I guess is time for a refresh, the chain is ~6 months old but I don’t track km per chain, annoying that Strava can’t do this. This must be at least the 5th chain since purchasing her (early 2018) so potentially chainrings as well? BB is also the original. Currently done 18530.7 km.

They don’t look too shark toothy but there is wear there, which I’d expect are

BB doesn’t spin fast, can’t say I’ve ever tried before mind you! And there is a noise if you turn the volume up.

I’m leaning towards new BB, new chain and maybe a bit longer before rings.

Oh and maybe a forum admin could add a “mechanical advice” tag as I’m sure I can’t be the only person who trusts this place more than the wretched hive of scum and villainy that is Reddit.

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I’d replace it all. Unless you installed the chain incorrectly, it’s possible that the chain rings contributed to the failure. It’s hard to tell what the BB problem is, but if you grab the crank and move it laterally, is there noise, or movement? If it’s been used primarily indoors then it’s very possible sweat got into it (replace it), and on that note, check your pedal bearings too. Taking a look at the headset just to rule out sweat in there too would be a good idea. And, if you sweat a lot down your arms and hands, replace the bar tape too, checking the pars for corrosion/rust.

If it’s used indoors, put a ‘bike thong’ on it. It won’t keep everything out, but it helps…

I added the “bike” tag as the closest since we don’t have a “mechanical advice” one at this time.

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those chainrings have plenty of life left in them IMO


Mine were worn like that and I was ‘advised’ to replace them. I usually, pre-pandemic, replaced the chain at the beginning of the season, and haven’t replaced chain rings in years. I do chain yearly, cassette 2 or 3 years, and chain rings almost never, but was told I really need to change them more often. :person_shrugging:

(Looks like it needs a cleaning too)

Do you have a chain checker? They are pretty inexpensive and very worth the purchase.

In my experience the more I keep my chain healthy, the chain rings and rear cassette last much longer.

You are due for cassette, I wouldn’t do chain-ring yet myself based on the picture, but could do them all at once, I just hate throwing “not worn out” stuff into the landfill.

When the whole system is worn out you will blow through chains. The shifting performance is noisy and jumpy even when well tuned.

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Yeah, but having the bike on the turbo just put maintenance out of my mind since she’s clean (ISH) and that’s when I normally do my checks. Stupid I know!

On my trainer trapped roadie, I found that replacing the chain and cassette really did quiet down the noise. Even outdoors, I could often sneak up on people because the whole drivetrain was that much quieter.

Early in the pandemic, I replaced a SRAM chain on my DI2 bike, with an official Shimano chain, and the difference was amazing. So much quieter.

OH!! Do not negate the possibility for sweat drenching the chain. It likes to get in the rollers, and then all bets are off. I had a fairly new chain develop seized links due to sweat penetrating the rollers in the links. Had to toss it because it was too far gone, and was surprised that it got so bad so quickly, and then discovered my Speedplay pedal bearings were nearly completely seized as well. All due to rust. (They use a single o-ring on the inboard end to protect the bearings. Yeah, maybe they need two?) And all of that failure due to rust was hidden my my noise cancelling ear buds!! I had to laugh. I was riding that noisy squeaky mess for months, not knowing it was that bad. Wild…

Not at all. Hop on and go. It’s what we do outside, but on the trainer it just focuses all that sweat onto the bike and bearings, etc. And bars, and all of it. I was nearly sick to my stomach when I was pulling the old tape off. Yeah, Hop on and go, and forget the maintenance is probably pretty common.

Nice to know I can probably skip rings, cassette should be good or at least shifting was fine when I last had the wheel in.

Might need it in the new year since I can’t remember when I replaced it, maybe 2 years ago.

I think I should start a sheet with dates replaced.

That’s why I used seasons (before the pandemic ruined it all). Easier to remember.

Rings look fine. What I tend to do is replace chain but have spares of rings and cassette in case existing doesn’t mesh with new chain.

Strava will track your component wear, even going back and calculating the mileage from the date you started using it.

Settings->My Gear->My Bikes

Click on a bike and then “Add Component” and you can specify the date you added said component and it will calculate the mileage to today, or add it for today and the mileage is tracked. When you replace that component you can retire or delete and add a new one.

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Well that’s new and cool.

Yeah, strava keeps track of all sorts of milage for components on my bike. Chain and cable are by far the most beneficial to me. Not new, been doing it atleast for 5+ years

Just had a look on chrome, and yes it must be there as a different bike has it chain recorded. Guess I started to record and then forgot.

Why not do it all. That way it will all wear in evenly. Black Friday deals.
Also new bar tape. I know a rider that rides the trainer a lot. His bars snapped while riding. Not a fun thing to happen. The bars looked like garbage under the tape.

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It’s not just my turbo bike so has fresh tape every spring, that’s just where I was when I broke the chain today.

As nice as a full refresh would be the cost difference between a chain at home or a chain and rings at home and a shop BB isn’t insignificant, but I wasn’t sure about the ring state hence asking - I’ve never replaced rings on the roadie before.

Gonna count the links and hope it was under 114 as my local has some 114 on sale.

BB swaps aren’t that hard. Some of the shops around here will let people borrow the tools to do the job, some won’t. But it’s not rocket science. The only thing I usually ‘farm out’ is bleeding hydraulic brakes. I kind of need them to work on occasion.