Bicycle Mechanics - Economics of chain/cassette replacement frequency

Apparently, I've gone "too long" with my 10-speed Ultegra chain, at about 1/16" over 12 inches. Though my mechanic offered to change my chain, suggested that for the price of the 10-speed chain (retail $40), I might as well keep going for a bit, since the cassette (retail $80) too would need changing, and as worn as it is I wouldn't be happy with just a new chain.

This is my first 10-speed bicycle. Said mechanic mentions that the Shimano Ultegra chain has always been roughly half the price of the Shimano-series cassette. This seems to have been the case back in the 9 and 8-speed Ultegra days.

I've gotten about 2500 miles on the chain, so assuming I do wait about 500-1000 more miles, that's 3500 for $120 versus, say changing the chain every 1600 miles and one cassette and another chain at say 3500 for $160.

The joys of modern technology. $0.015/mile for chain and maybe another 0.02-0.03 cents
per mile for cassette. I would say, buy the chain and fit it and see if the cassette tolerates.
If the casssette does not object, continue on with the new chain and old cassette.
Most of the time this works, at least it always has in the past. You won't get more than
two chains per cassette however. If you continue on with the same chain, you will certainly
get into the cassette replacement scenario with a new chain. You won't damage
the new chain by riding it long enough to evaluate cassette incompatibility.
Clean the cassette before putting on the new chain though.

+1 on the chains/cassette.

Old cassettes tolerate newer chains at some level. Old chains typically do NOT tolerate new cassettes.

In the old days guys would have two chains and swap them out weekly or monthly. But with the pins and stuff that's not really practical.

To check your chain, put it in the small ring and a cog you use a lot (or one of the smaller ones) and, while sitting, push very hard while going slow. The chain will jump if it wants to. Don't stand else you'll sit really hard on the stem or top tube, not fun. Check all the gears while in the small ring, and if things seem fine, you'll be fine.

cdr

The debate between very frequent chain replacement to "protect" the cassette or running them both for a long time and replacing both together is an annual event.

If you are using a very expensive cassette, say a Record Ti or Dura Ace, then frequent (and that may mean every 1000 miles) chain replacement makes sense since the cassette is $200 or more. If you are using low cost cassettes, then changing a $25 chain a bunch of times to protect a $50-$70 cassette is not good economics.

I get 5000 miles or more out of a Shimano 9-speed or Wippermann 10-speed chain and change both the chain and cassette (Ultegra, 105, Veloce, etc.) together.

I just paid $25 for an 8-speed chain and $18 for a cassette. First I replaced the chain but the new chain was skipping on the old cassette. The fact that the chain was more expensive than the cassette makes me think I should just keep riding on the old chain and cassette and plan to replace them both when they stop functioning as a set. However, chainrings are substantially more expensive. I don't have a feel for how long I can let the chain go before I damage the chainrings. So I guess I will stay with the new chain and cassette.

Chainrings are easy enough to inspect. That said, chainrings tend to last a long, long time - much longer than your cassette.

I love this kind of discussions. It reminds me how happy I am to be a singlespeed cyclist. My whole drivetrain lasts longer, and the rear cog which I seldom have to replace (steel singlespeed BMX cog, straight teeth) costs much less than a cassette.

Also consider that a worn drive system, even if it has worn together such that it doesn't slip, is 2-3% less efficient than a new, unworn drive system (according to Rohloff). Not a big deal for recreational cyclists, but definitely a factor for serious racers.

I just paid $25 for an 8-speed chain and $18 for a cassette. First I replaced the chain but the new chain was skipping on the old cassette. The fact that the chain was more expensive than the cassette makes me think I should just keep riding on the old chain and cassette and plan to replace them both when they stop functioning as a set. However, chainrings are substantially more expensive. I don't have a feel for how long I can let the chain go before I damage the chainrings. So I guess I will stay with the new chain and cassette.

Lol. You paid too much for your chain.

Also consider that a worn drive system, even if it has worn together such that it doesn't slip, is 2-3% less efficient than a new, unworn drive system (according to Rohloff). Not a big deal for recreational cyclists, but definitely a factor for serious racers.
I'd really like to see evidence of this efficiency loss. As long as the chain is clean and reasonably well lubricated, it doesn't make mechanical sense to me.

As noted, chainrings last a LONG time and will tolerate worn and new chains with equal performance until they are very badly and obviously worn out.

If the chain measures an accurate 1/16" over a 24 pin length then you should be able to replace the chain only and keep on riding. I've done that at least 3 times with 9-speed and 10-speed chains with absolutely no chain slip. I get at least 5000 miles out of a chain.

Al

I'd really like to see evidence of this efficiency loss. As long as the chain is clean and reasonably well lubricated, it doesn't make mechanical sense to me.

As noted, chainrings last a LONG time and will tolerate worn and new chains with equal performance until they are very badly and obviously worn out.

+1

Why not just replace the worn out cogs on the cassette? Not all the cogs get used the same amount. Cost?

Why not just replace the worn out cogs on the cassette? Not all the cogs get used the same amount. Cost?
This used to be practical when freewheels were common and every LBS had Sun Tour and Shimano and sometimes Campy "cog boards". You just bought the ones you needed and kept the others. Building your own custom freewheel was also practical and often done.

That pretty much went away with the introduction of cassettes and the various shaped teeth that made indexing work so well. Cogs were made for specific cassette configurations and mix-and-match was less useful and not supported by the manufacturers. Cog boards vanished.

Also, while individual cogs are available, not all tooth counts are and the price of individual cogs is so high that replacing three costs more than an entire 9-speed cassette.

Why not just replace the worn out cogs on the cassette? Not all the cogs get used the same amount. Cost?

I've replaced several individual cogs but this was to build a custom cassette not normally available. With many of the higher quality cassettes the larger cogs are pinned together in clusters and cannot be used or replaced individually. The synchronization from cog to cog hasn't been an issue on custom cassettes I've used.
Like HillRider said, replacing individual cogs usually isn't cost effective when compared to new cassettes unless you have a source for good individual cogs below retal price.

Al

T
You won't get more than
two chains per cassette however.


Another case of "your mileage may vary". I have over 18,000 miles on my DA cassette and its 5th chain. This last chain skipped a bit on the 17 until it wore enough to break in. The new cassette is in the drawer waiting for the next chain change. It's going to cost to ride a bike. I'm over it.

Another case of "your mileage may vary". I have over 18,000 miles on my DA cassette and its 5th chain. This last chain skipped a bit on the 17 until it wore enough to break in. The new cassette is in the drawer waiting for the next chain change. It's going to cost to ride a bike. I'm over it.

I don't disagree, as the front drive (8spd KMC chain, Ti 6spd Indian sourced cassette and Ti drive ring)
on my Rotator Pursuit hung in for 16,000 miles before sudden decrepitude made its appearance.
Chain still had less than 1/8 (a bit under 3/32 actually) elongation. Had to change the cassette, chain
ring and chain before it all worked ok. One case where $5-15 cheap steel 7-8spd cassettes from
Nashbar allowed a DIY cassette 12-32T 6spd. The rear drive on the same bike, a 9spd set up is on the
3d chain and 3d cassette. Figures.
My usual experience based on 70kmi from the 70s and
past 10yrs is 3 chains per most used CW, 2 chains per cassette. Most used CW is usually the 42T
on my triples. The 30T will probably outlast me. The 52T will probably go 4 chains or even 5.

^^^How the heck does your chainwheel live only 3 chaisn (haha, lifespan measured in chains, I like it)? It could only be if they are aluminum chainrings. Even then, a bit low count.

^^^How the heck does your chainwheel live only 3 chaisn (haha, lifespan measured in chains, I like it)? It could only be if they are aluminum chainrings. Even then, a bit low count.

Uh, ALL good quality chainrings are aluminum. I do agree that's a pretty short lifespan for chainrings. I've had them last 30,000+ miles and still work well.

^^^ So what makes an aluminum chainring better quality than a steel one? The fact that it's 2 grams lighter?

^^^ So what makes an aluminum chainring better quality than a steel one? The fact that it's 2 grams lighter?
First it's a lot more than 2 grams difference. For example, A 26T granny ring is 50 grams in steel and 25 grams in Al. The difference for a 53T road ring would be far more dramatic.

Second, it doesn't matter what you think of the benefits, the facts are that all good quality chainrings from all manufacturers (Shimano, Campy, TA, SRAM, Stronglight, etc.) are aluminum. The sole exception is a steel granny ring used on MTB cranks and even they use aluminum larger rings.

Factor in the cost for new chain rings, too. Riding with a worn out chain will accelerate wear on the rings, and they're expensive.

I find relatively frequent chain replacement allows long life for the cog set, and especially the rings.



Apparently, I've gone "too long" with my 10-speed Ultegra chain, at about 1/16" over 12 inches. Though my mechanic offered to change my chain, suggested that for the price of the 10-speed chain (retail $40), I might as well keep going for a bit, since the cassette (retail $80) too would need changing, and as worn as it is I wouldn't be happy with just a new chain.

This is my first 10-speed bicycle. Said mechanic mentions that the Shimano Ultegra chain has always been roughly half the price of the Shimano-series cassette. This seems to have been the case back in the 9 and 8-speed Ultegra days.

I've gotten about 2500 miles on the chain, so assuming I do wait about 500-1000 more miles, that's 3500 for $120 versus, say changing the chain every 1600 miles and one cassette and another chain at say 3500 for $160.

First it's a lot more than 2 grams difference. For example, A 26T granny ring is 50 grams in steel and 25 grams in Al. The difference for a 53T road ring would be far more dramatic.

Second, it doesn't matter what you think of the benefits, the facts are that all good quality chainrings from all manufacturers (Shimano, Campy, TA, SRAM, Stronglight, etc.) are aluminum. The sole exception is a steel granny ring used on MTB cranks and even they use aluminum larger rings.

The Shimano Sora crank used to come with steel rings. As a triple that thing was a tank.

The Shimano Sora crank used to come with steel rings. As a triple that thing was a tank.
Right, and some low-line MTB cranks had all steel rings too. Some were even riveted on so you had to replace the entire crank when they wore out.

But, as I said, every crank above entry level from every maker uses Al chainrings.

Back to chains, I always have used the rule of thumb that 1/16" meant that the cogs were likely ok and that 1/8" is the point at which they are pretty much cooked.

My last geared bike was a MTB with Deore crankset - it had steel chainrings. Furthermore, I think you can still buy all-steel 3-part chainring sets today, so I just take issue with the usage of past tense.

My last geared bike was a MTB with Deore crankset - it had steel chainrings. Furthermore, I think you can still buy all-steel 3-part chainring sets today, so I just take issue with the usage of past tense.
I did say above entry level they all have Al rings. The Deore is one of Shimano's lower level mtb groups and, as mtb components, they are subject to dirt, mud and wear that road components are typically not. However, that notwithstanding, all of Shimano's better MTB groups have Al rings.

There seems to be two theories to follow:

• Replace chain when a chain checker has deemed it "stretched".
• Ride chain and cassette together indefinitely; replace both in about, oh, 10 years.

If you don't buy expensive cassettes, as I don't, just let the chain and cassette mesh together. It certainly is the easier route, especially if you have multiple bikes and can't track milage easily.