Unusual chain/sprocket wear?

Sanders

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Region
USA
City
PNW
Como 4, 275 miles.
Just did a quick cleanup to throw a bit of fresh chain lube on. The teeth of cassette sprockets look worn in a strange pattern. The chain seems a bit hammered too. Quick wipe down and oiled a couple weeks ago but that's all since came from dealer. Didn't really look at it that close until I cleaned off sprocket grime tonight. Yikes! Wifes Como 3 with 750 miles looks much better, almost new.
 

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Do you consciously let up on pedal pressure when you shift? The Como/Vado series don't have a software function that eases motor torque when you're about to shift. They rely on the rider to do that. Otherwise you're moving the chain under very high tension making for unhappy gears.
 
I do understand the torque sensing of motor and do not make demands without being in full motion. I'm a mechanic by trade and I was attracted to the Brose concept. My wife's bike we bought used, 500 miles on it. Shes not as aware. Totally different looking cassette. I have noticed for quite some time that the gear changes have been really loud mechanically and it felt like I was changing 2 gears at a time as it wasn't the response I was expecting. Something's just a bit odd here.
 
Looks normal to me. The cassettes have many different tooth profiles specifically for chain pickup and release. A worn cassette would have much thinner tops to the teeth bordering on pointy, but yours are still broad and flat.
 
Are you asking about the bevel edge, or am I missing something else? A severely worn tooth will come to a point, or have a curve where the roller contacts the tooth. Don't see any of that. What are you using for chain lube? Looks dry and dirty for being lubed a couple weeks ago.
 
Sierratim: what I think I meant was that I won't change gears and step on it before the gear has completely enganged. I'm not real demanding of it, haven't ever gotten off seat to peddle
rich c: i had just cleaned moments before picture, pedro's dry lube as we are in a very/dusty climate. little humidity or moisture
 
Sierratim: what I think I meant was that I won't change gears and step on it before the gear has completely enganged. I'm not real demanding of it, haven't ever gotten off seat to peddle
rich c: i had just cleaned moments before picture, pedro's dry lube as we are in a very/dusty climate. little humidity or moisture
Are you having any shifting problems?
 
Como 4, 275 miles.
Just did a quick cleanup to throw a bit of fresh chain lube on. The teeth of cassette sprockets look worn in a strange pattern. The chain seems a bit hammered too. Quick wipe down and oiled a couple weeks ago but that's all since came from dealer. Didn't really look at it that close until I cleaned off sprocket grime tonight. Yikes! Wifes Como 3 with 750 miles looks much better, almost new.
Looks exactly like mine did when I asked the question. It's the way they are designed to be, on my Spark bike.
 
I think I was mostly reacting to the biggest gear. Just wasn't expecting anything but clean looking teeth and saw a few that looked a bit hammered. Lots of wear on chain plates/links that made it look like it struggled to get to next gear. This all may be normal, thus the question.

I have had a lot of noise when changing gears. Sometimes feeling like I went up or down 2 instead of the next 1. Dont recall hearing that type of noise from her bike as we ride together. Believe me, I'm not pumping on it that hard.
 
I think I was mostly reacting to the biggest gear. Just wasn't expecting anything but clean looking teeth and saw a few that looked a bit hammered. Lots of wear on chain plates/links that made it look like it struggled to get to next gear. This all may be normal, thus the question.

I have had a lot of noise when changing gears. Sometimes feeling like I went up or down 2 instead of the next 1. Dont recall hearing that type of noise from her bike as we ride together. Believe me, I'm not pumping on it that hard.

Sounds like you may need to tweak your derailleur adjustment. It's not uncommon to get a bit of cable stretch after a few hundred miles. Tightening up the shift cable with the inline barrell adjusters usually takes care of this.

This Park Tool article and video cover the full range of derailleur adjustments. Check out the indexing section.


Current specs on the Como 4 call out the Shimano HG500 10-spd 11-42t cassette.

shopping (1).jpeg

The tooth shapes and ramps are all intended to help the chain jump gears smoothly when shifting with the pedals in about the 2:00 position.

The Como 3 specs the Shimano HG200 9-spd 11-36t cassette. It's ramp and tooth shapes are different.
 
Sounds like you may need to tweak your derailleur adjustment. It's not uncommon to get a bit of cable stretch after a few hundred miles. Tightening up the shift cable with the inline barrell adjusters usually takes care of this.

Before you attempt any cable adjustment, confirm the the derailleur hanger is straight; this is the piece that the derailleur is attached to. When you look at the derailleur from the rear of the bike, it should be hanging completely vertical. if it is not, then the hanger or possibly even the derailleur itself is bent. No good gear adjustment can be performed until the derailleur is aligned.
 
Will look at derailleur mount first.

Upon further review as I stared at the teeth long enough I did notice some seemed intentionally different. Apparently for a reason. Very clever. Cable stretch makes a difference too. Funny how I didn't think of that as an elevator mechanic. Cable stretch is a big thing in my biz. Just getting old I spose.

I could just take it to LBS where I got it and will if its deeper than this but can't imagine not riding this evening after work. They're quite busy.

Thanks for the info folks!
 
Will look at derailleur mount first.

Upon further review as I stared at the teeth long enough I did notice some seemed intentionally different. Apparently for a reason. Very clever. Cable stretch makes a difference too. Funny how I didn't think of that as an elevator mechanic. Cable stretch is a big thing in my biz. Just getting old I spose.

I could just take it to LBS where I got it and will if its deeper than this but can't imagine not riding this evening after work. They're quite busy.

Thanks for the info folks!
Have a great ride!
 
Upon further review as I stared at the teeth long enough I did notice some seemed intentionally different. Apparently for a reason. Very clever.

If you take a closer look at a new Shimano cassette - attached - this is confirmed.
Nothing wrong with your cassette - apart from cleaning needed ;)


Shimano CS-M8000-11 11_46.JPG
 
I did tighten cable slightly.
Smoother now. Awesome.
As I look at that cassette pic from sierratim I see that my semi-clean unit does look just like it. I also looked at a picture of a new chain. Looks just like mine now. Apparently they are built in a way to make it all work together. Once again, very clever. Guess it's all more sophisticated than I thought. Before this my bike experience was a knock-off Schwinn varsity during the late 60's. (Did I say that? Was my microphone on?) My knowledge base is increasing and I appreciate the help.
 
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