Berns1

Hey,

SO I have a trek bike that I cycle to work everyday, max kilometers a week 100. I had my chain and cassette replaced in Feb and just had my bike in for a service and the guy said that the cassette will have to be replaced within a month or two max. is there anything anyone can recommend to me to do to help the cassette last longer? I would have thought that I would get longer from the cassette? Thanks guys for any ideas

zeeway

Try a different bike shop...

KevinF

Are you cleaning / lubricating your chain periodically?

Regardless of how clean you keep a chain, they will wear out. Worn chains in turn wear down cassettes. If you replace the chain before it's too badly worn then the new chain should work just fine with the old cassette.

If you put a new chain on and the chain starts skipping on the gears then you waited too long; i.e., you need to replace the cassette as well.

For reference, I ride around 250km a week, April through October and a cassette lasts me easily two or three years.

Trakhak

Use the big chainring with one of the larger sprockets whenever possible (i.e., on level or nearly level ground) instead of the small chainring with one of the smaller sprockets (the smaller sprockets wear more quickly than the larger sprockets).

cny-bikeman

+1 The range for each chainwheel with the rear cogs overlaps, so if you find yourself riding quite a bit on the smaller cogs try riding the next larger chainwheel with a larger cog. The odds are high that you can find a combo that is close in gear ratio (feels the same) and wear will be much lower. Here's a page that allows you to plug in the chainwheel and cog sizes so you can visually see equivalent ratios: Bicycle Gear Calculator. Interestingly it also allows one to adjust the max angle of the chain, so you can see what gears have a high angle that can increase wear.

Also, shift so as to spin the pedals at a rate of at least 75 rpm (cadence) as a higher rate both reduces wear (same speed in a lower gear) and is more efficient. Some incorrectly believe that lugging lower gears gets one in better shape. I spin at a rate of 90+ and take forever to wear out a chain.

Finally, lube but don't overdo it. Wipe off excess, especially if you using a heavier lubricant.

I would note that manufacturers increased the wear problem by choosing to add smaller and smaller cogs (and often marginally useful gears) instead of decreasing jumps between gears or offering lower gears. Somehow racers managed to ride fast in the past with only a 13 (or 14 if you are old enough) tooth small cog. Yes, there's a small reduction in weight due to shorter chains and smaller chainwheels, but at a cost for the consumer, who does not have a sponsor to absorb increased parts wear.

p.s. Although all of the above is true I would question the ability of anyone to accurately assess cog wear except at the extreme end. The most common way to find out a cassette is worn is skipping or noise when a new chain is installed. I would ask the mechanic how he decided that the cassette needs replacement, as even with poor condition I can't see wearing out a cassette in a few months.

pdlamb

This is how you know your cassette needs to be replaced. (Replace the chain within a few days, if not immediately, when this happens.) This sounds like the "your brake pads are 50% worn out, you'll need to replace them" auto repair scam. (Yes, if you've driven the car 10,000 miles, you'll need to replace them in another 9,000 miles.) Changing a cassette is easy, and apparently pretty profitable, for the shop to be pushing a replacement in two months.

Trakhak

Small correction (no pun); otherwise spot on.

cpach

That seems way too often, given your stated average distances.

To make your drivetrain parts last the longest, appropriately lubricate and clean your chain, and buy a chain wear indicator and replace the chain its worn. Many of these tools overmeasure chain wear somewhat, but you'll be sure to not be riding on an over worn chain. Replace cassettes when skipping occurs. If you ever get skipping with new chain and cassette, replace the chainrings.

maddog34

two other things to consider... get a better quality cassette, maybe? and back off the torque you're applying as you shift.

there is a vast range of different quality cassettes... can't be sure what grade your cassette is, but i'm suspecting it may be a really low grade one.

and CLUNK shifting beats up gear teeth.

noglider 

If you let your chain get really dirty, the grit will cause the chain to wear prematurely, which will cause your cassette to wear prematurely. If you don't want to clean your chain, and I don't blame you, replace it prematurely. This is the less wasteful thing to do.

velocentrik

Chainrings, chains and cassettes work as a team.

If your previous chain was worn to the point of being allowed to stretch, thus causing accelerated cassette and chainring wear, and you replace the cassette and chain but not the chainrings you kind of transfer the stored up chsinring wear through the chain to the new cassette.

With a new bike, or drivetrain, good mechanics always recommend rotating multiple chains. With 7/8 speed you rotate three new chains, 9 speed four chains, and 10/11/12 speed use five chains. You don't want to wait too long to rotate chains. It's especially important to rotate quickly the more speeds you have on the rear cog stack since the cogs are narrower and wear faster. You can get away with every 500 miles 7/8 speed, but you need to rotate 9 mor often and 10/11/12 earlier still.

The multiple chain rotation will optimize getting max mileage out of the cassette and chainrings.

velocentrik

Also at 100km week you've put 2400km on the bike since February. Entirely possible you've worn out a new chain and cassette if you matched the two new components to the badly worn chainrings.

There is nothing remotely difficult about changing a cassette, chain, or chainrings. The required tools are minimal. Any cyclist can be servicing those components themselves anyway.

shelbyfv

When you follow this practice and get your cassettes to last through five chains, do you change the cassette when the first chain measures too long or do you run each of the five until they are all too worn? At what mileage do you change 10 or 11 speed chains? thanks

davidad

The multiple chain thing isn't the greatest idea in the world. I remove my chains every 800 to 900 miles and clean them in an ultrasonic cleaner. I lube my chains with a mix of chain saw bar oil and unscented mineral spirits.
I replace my chains after they measure 1/16" war in 12".
The smaller cogs wear out after 20 to 25k miles.

shelbyfv

What do you guys think is the best way to keep track of the 5 chains? Maybe a separate ziplock for each with some markings system? What do the good mechanics do? Also, do the 5 chains need to be the same brand and model?

caloso

I have never heard of this.

ThermionicScott 

I call shenanigans on the aluminum chainrings causing the new chain and cassette to wear prematurely as well.

Rotating chains is a good idea, but shouldn't be necessary for the OP to make his cassette last more than a measly ~1500 miles. I think there's more to the story that we're not privy to. Could just be that the shop is relying on those chain checkers that measure a brand-new chain as already half-worn.

Racing Dan

Maybe he is just trying to sell some more parts? Hard to call ...

To keep cost down you could learn how to do basic maintenance like replacing chain and cassette. Minimum skill, time and tools are required. Tools pay for them selves first or second time you use them. If its ultegra 11sp you can substitute 11sp 105 for lower cost.

Barabaika

There is no reason to use anything higher than 8-speed components for commuting purposes.
8-speed components last much longer and are 4 times cheaper.

An 8-speed chain is about $10, an 11-speed one is $40.
An 8-speed cassette is $20, an 11-speed one is $70.

shelbyfv

I don't think OP said what components he has. 5800 chains are $22 and cassettes $37 at Ribble and others. However, apparently good mechanics always advise rotating 3 chains per 8 speed cassette as opposed to 5 for 11 speed, so definitely less maintenance with 8 speed!

caloso

Your solution would require the OP to buy an 8-speed group to replace his current drivetrain. So you need to factor that cost in as well. Or the OP could keep using the bike he has and spend a little more time cleaning and lubing.

79pmooney

I didn't see anyone here talk about chain "stretch". Quotations because it is really wear in the pins and rollers, not actual stretch.

OP, measure 12 pairs of links, from beginning of a pin to the beginning of a pin 12 pairs later with the chain stretched out. If the distance has reached 12 1/16", replace the chain. If it exceeds 12 1/8", it is well worn. If the chain is past 12 1/16" and hasn't reached 12 1/8" yet and all is working, keep riding. As long as everything works, don't do more than clean and lube what you've got. (You can keep two or more chains going if they both have roughly equal stretch and still work. This will extend the life of your cassette and chianrings. But start saving your money. When things no longer work well, it will be time for a new cassette and chain (and maybe chainrings). This time get 2 or more chains as suggested above and follow their routine.

Once you have new stuff on, keep a close eye on chain stretch, always using a ruler. The quickie "chain checker" have a built in error, adding roller play to roller wear. The play has nothing to do with the issues we are trying to address, but does serve to help bike shops sell a lot more chains and cassettes.

Ben

Barabaika

If I estimate his expenses correctly and he has high-speed components, he pays $100 for an 11-speed chain and a cassette each 6 months plus $50 for the installation. If he has a fancy shifter, that will break down quickly too.
You can get an 8-speed chain + cassette + shifter for $150.

noglider 

I don't see any advantage in rotating new or partly worn chains. I replace the chain when it's worn or nearly worn.

shelbyfv

Surprised you would admit that! Per post #11, we know that "good mechanics always recommend rotating multiple chains" and the correct number is 5 chains for 10 and 11 speed.