# How Long Should a Drivetrain Last?



## m85476585 (Jun 7, 2007)

The cassette and chain on my commuter are starting to get worn out again, and they are only a year old. I ride a few miles a day, so my best guess is that I have about 300-500 miles on these parts. I haven't measured the chain yet, but the cassette is visibly worn in the gear I normally use (It's 7 speed but I ride it like a singlespeed- just don't shift), and it's starting to skip more if I do shift.

Is it normal that my drivetrain appears to be worn out after such a short time?

I've thought about just converting it to a singlespeed, but I don't want to give up gears because I use this bike for everything from carrying loads of groceries to long road rides, and I don't want to give up low gears when I need them or high gears when I want to go fast.

The cassette is a Sram PG730 and the chain is a Sram PC-850.


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## Toff (Sep 11, 2004)

It does seem short but if that model is made out a softer metal then what can you do.

I get about a year+ out of the 9 speed PG-990 cassette but I ride alot more than 500 miles on it. Also I'm sure its more expensive but still only $70 or so. I've found that the heavier chains tend to last longer than the ultra lightweight chains so I just go cheap on the chain.

Just try a different brand/model or if its cheap enough then buy them again.


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## Squash (Jul 20, 2003)

m85476585 said:


> The cassette and chain on my commuter are starting to get worn out again, and they are only a year old. I ride a few miles a day, so my best guess is that I have about 300-500 miles on these parts. I haven't measured the chain yet, but the cassette is visibly worn in the gear I normally use (It's 7 speed but I ride it like a singlespeed- just don't shift), and it's starting to skip more if I do shift.
> 
> Is it normal that my drivetrain appears to be worn out after such a short time?
> 
> ...


If you use the bike daily for short ride, grocery runs, and long road rides, I'd bet you have more than 300 to 500 miles on it. I mean if you ride 5 miles a day 5 days a week, that's 1300 miles right there. Bump that to 6 days a week and your looking at 1560 miles.

So yes it is entirely possible that your cassette and chain are worn out again, and not unreasonable at all. It's possible to get more mileage out of the components, but there are too many variables to predict how much more. Things like chain cleaning and lube, the conditions you ride in, quality of the components, etc., all play into it as well. And being Johnny one speed on a multi speed bike doesn't help either. Your favorite gear combination is obviously going to wear faster than the rest.

Replacing a chain once or twice a year is not uncommon at all. I can usually get around 1000 commuting miles out of my chain, and I can usually get 2 or 3 chains worth out of a cassette. But I clean and lube the chain regularly, check the chain weekly for wear, and inspect the cassette carefully every couple of weeks or so. I also replace the chain before the checker or my measurements say the chain is completely worn out. Usually at about the 75% mark.

Anyway, I'd say double check you mileage, you may be surprised at what you come up with. If you are only getting 3 to 500 miles out of the system, then there is something wrong. Whether maintenance frequency, gear choice, component quality, etc., only you can say.

Good Dirt


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## woodway (Dec 27, 2005)

I have 10,874 miles on my current cassette (one of the SRAM PG series of10-speed cassettes). Chains are replaced when they measure 1/16" longer than 12", which usually works out to be every 2000-3000 miles. Your components should be lasting much, much longer than 500 miles. Cleaning and lubing your drivetrain on a regular basis will make it last much longer.


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## CommuterBoy (Oct 4, 2007)

I get about 2000 miles out of Sram PC850 and PC950 chains, including riding through winter with slush/grime, etc... and I have gone probably 8k on a rear casette... normally 4-6k. All of my riding includes dirt. Woodway I'm assuming that 10k is paved, and at least fairly regular cleaning/maintenance? That's an impressive amount of miles on a cassette!


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## ranier (Sep 9, 2003)

Two to three chains per cassette and that's making sure to change out the chain once it's past it's serviceability with a chain checker tool. 

I haven't had to change out my chainrings on my commuter yet. Race Face rings seem to have a long serviceable life if you keep up with the chain.


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## jrm (Jan 12, 2004)

*Check your chain for stretch-ware*

You may have just worn the chain more then anything else and its an easy fix.


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## woodway (Dec 27, 2005)

CommuterBoy said:


> Woodway I'm assuming that 10k is paved, and at least fairly regular cleaning/maintenance? That's an impressive amount of miles on a cassette!


Yes, all paved, combination of rural roads, MUPS and city streets. I am pretty dilligent about keeping my drivetrain clean and lubed, because I HATE any kind of squeaking or grinding noises coming from my drivetrain. Makes me absolutley CRAZY. I am a little whacko that way. ut:

In the winter, I clean/lube at least weekly, sometimes more often, depending on conditions. In the summer I clean lube at least every two weeks, again sometime more often.

I have noticed in the last couple of months that shifting is not as crisp which tells me that it's probably time for a new cassette...


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## metro2005 (Oct 5, 2011)

My chain and cassette on my recumbent have a little over 3000 miles on them and no sign of extreme wear yet. On my hybrid bike i have over 7000 miles on the cassette and its still not worn enough to replace it. The chain has been replaced 3 times due to rust from salt in the winter.


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## SimpleJon (Mar 28, 2011)

I do 50Km commute per day 5 days a week on my hybrid mostly on fastish roads. I think it depends on what's installed on it The stock 7 speed Acera lasted about 2500Km (chain and cassette), the hubs did about 1000Km more, the nasty and pointless NE1104 suntour sus forks were buggered by about 5000Km, I replaced them with a set of steel rigid.The crank also used to flex too much.
As I use it on roads mostly I now have it set up with a 105 triple 29/39/50 crank and 10 speed ultegra RD and cassette - with flat bar shifters - also the second time the el cheapo wheels / hubs wore I built myself a set of roadie training wheels on 105 hubs, that will take 25mm to 32mm tires. 
I do about 8000Km (5000 miles per year) and have gone through two chains, in 15months since this set up. everything else is still fine.
Funny thing is the 7 speed Acera RD is still going strong, I kept it - when I broke the XTR carbon RD on my MTB It worked fine as a stop gap on a 9 speed XT/XTR drive train


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## Mr.Magura (Aug 11, 2010)

woodway said:


> I have 10,874 miles on my current cassette (one of the SRAM PG series of10-speed cassettes). Chains are replaced when they measure 1/16" longer than 12", which usually works out to be every 2000-3000 miles. Your components should be lasting much, much longer than 500 miles. Cleaning and lubing your drivetrain on a regular basis will make it last much longer.


This matches my experience as well. 10 speed drive trains do last shorter than 8 speed though.

Back when using 7 speed for the road bike, I hit around 25.000km on regular basis for a cassette. On the MTB I had to change the cassette around 15.000km.

The grand difference is determined by how clean your drive train is, and how well lubricated it is.

Nothing beats bar oil, no matter what the snake oil manufacturers claim. It's a mess, yes, but it will keep your drive train alive and free of rust for a long time.

Magura


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## highdelll (Oct 3, 2008)

Mr.Magura said:


> ...
> Nothing beats bar oil, no matter what the snake oil manufacturers claim. It's a mess, yes, but it will keep your drive train alive and free of rust for a long time.


truth :thumbsup:


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## m85476585 (Jun 7, 2007)

I measured the chain today with a Park CC-2 and it says 0.5%


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## highdelll (Oct 3, 2008)

I measured mine w/ a ruler and it was 12-1/32"


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