How long does a drive train last?
 

When I had about 1000 miles on my Bianchi San Remo, I took it to my LBS for a thorough check out and ‘tune up’. I was told that my chain and cassette would be worn out in about 500 miles and that the sprockets would last until about the 2000 to 2500 mark. The mechanic told me that this is normal, and upgraded components would not last much longer.

Up till now my bike shop has been very honest; so I have no reason to doubt them, but this suppressed me. Is this the normal mileage for a drive train?

It depends very much on how rough you are with your equipment.
I've always heard that having a Sachs (formerly Sedis) chain is better than any other chains, and I've read that Sachs now even has chains that can be removed wit less tools than before... good for lazy slobs like me :)
From what I understand they advise to change chains every 2000K to diminish wear and tear on sprockets. Old Shimano sprockets (Uniglide) could be reversed so that you had double kilometrage/mileage. New sprockets (Hyperglide) are pre-worn so that it's not only impossible to reverse them, they also wear down faster than the UG-sprockets used to do.. tripling of profits on sprockets of course...!
I'm still using UG sprockets on my touring bike..

All this is valid in summer.. in winter with cold weather, mud and rain and above all salty roads, wear and tear can be twice as fast ..

Finally friends of mine are more fastidious/less lazy and they alternate 3 different chains and thus change chains every 800 K (500mi).

It can be quite costly to not remove a chain on time as then a sprocket will have been worn out as well... my, I really need to visit that LBS again.. haven't done it myself in ages..
:(

Hope this helps!

Keeping your drive train CLEAN is the only solution to long life. By doing so you can probably extend the mileage given at the LBS.

The shop is playing you for a sucker. Even riding in winter salt and sand, 500 miles is pretty short. With regular cleaning, any cogset and chain should last you better than 2000 miles. Unless these guys are offering to replace your cogs at 500 miles for free, I wouldn't set my feet in that shop again. They are theives.

As said.. these friends ALTERNATE chains every 800K to get a more even wear and tear.. they don't buy new ones...

If you don't like wear and tear, buy a fixer or a single speed bike.. I had a coaster bike that used the same chain for nearly 20 years.. rode approx. 3000K/year with that one.. 60 000K with one chain is pretty good, isn't it
Lubing was probably done about once a year :lol:

Ivana

Alex, I was not clear enough.

At the 1,000 mile mark the mechanic warned me that 'for now' the drive chain is fine and I would probably get 500 more miles out of it (for a total of 1,500 miles on the original set).

Ok - so here's the next question. . . .

I'm now getting close to the forewarned 1,500 mark. So far everything seems OK. What (on the bike) will tell me that I need a new chain and/or cog set?

Yep, I guess I'll have to start doing that. I really haven't done much besides an occasional spray of lube.

Usually the chain will 'skip' on the smallest cog under heavy load (fewer teeth = faster wear).

Incidentally, if you were to put a new chain on now it might skip immediately, illustrating the wear on the cassette.

I used to agonize over how frequently to replace a chain, but Sheldon has reduced it to an exact science: every few months, measure the length of 24 half-links, and replace the chain if that length exceeds 12-1/16 inches. This practice will definitely reduce the wear rate of your cogs and chainrings. 2000mi or 3000km sounds about right to me, but "your mileage may differ."

Note also that microdrive systems wear out much faster than full-size or road systems -- chain tension is greater, and fewer teeth are bearing the load. Unless you race, avoid 11 or 12T cogs entirely. Avoid cross-chaining, and try to use more than just the same few gear combinations. (I save my lowest gears only in desperation, cruise at high cadence / light tension in my highest gears, and therefore tend to wear out my medium and low-medium cogs first.)

The easiest thing to do is, get a chain gauge, it takes away the guesswork and the task can be accomplished with with one hand ( Park makes a good one), check your chain regularly and replace as needed. If you keep "on top of your chain" your cassettes and chainrings will last much longer. The Sachs chains will wear last much longer than the "stock" chains but, in some cases they may not shift quite as precisely. Keep your drivetrain clean too, it will help it last longer as well. The 1500 mile "mark" is only a guideline, there are some who need to replace thieir chain every 500 miles, ( can you say "ANIMAL"?), others can get away with 2000 or more.

Ride Clean
Pat

I'd add that it can happen in lower gears, too, under hard acceleration/high chain tension situations. If the chainrings are worn, the problem is exacerbated when you put on a new, unstretched, chain.

Even with a completely neglected drivetrain, it's unlikely to be a problem at 1500 miles.

As described above, there are many ways to check for yourself the questions or answers you have from your LBS.

Strive to learn as much as you can and need them (the LBS) as little as possible.

Keep that drivetrain clean!

I intend to do just that, and I can thanks to the great advice I get on this forum.

Specifically, I think I’ll change the chain and rear cogs sometime before spring. (if we get a big snowfall, I’ll have the LBS do it then). Then I’ll get a gauge and perform regular maintenance and checks on the chain, replacing as needed.

Thanks again to all for your help.

Since I have done time in a shop I'll give you a perspective. This isn't gospel. This opinion and several $ will get you a drink at Starbucks.

The guy in the shop that told you that 500 miles is the limit on the chain is well informed. He is staying on top of trends and information. That is the current recommendation from Shimano. Many in the bike industry don't know that. That said, I find that since I do a lot of stop/start, hills, and I'm heavy, 1500 miles is what I get from a Sachs PC-58 (most of my bikes are 3X8). I don't clean them nor care about them--I throw them away and spend the $20 (cheaper than a tank of gas) and forget it (I don't MTB in mud). When my cogs start to skip, it is usually the 11t cog in the rear--that is a separate orderable part. After about 4 chains I had to replace it on my commuter--about $12. (A shop should charge about $40 labor replace both items, this is because they will assume the derailleurs will need adjusting, and if the shifting isn't right when you pick it up, you will and should bring it back and they will have to adjust them anyway and not get paid for it). Chainrings rarely wear out. 15000 miles are not unusual on road bikes, what often wears out are the shifting ramps or pins (on Shimano chainrings) creating sloppy shifting, however more often than not, that is masked by the pivots being so sloppy in the derailleurs by that time, that the service writer will asked if you wish to replace or repair your bike.

So what I the guy in the bike shop is telling you is keep an eye on your bike. A catastrophic failure, by chain break or cog skip is usually found under HEAVY load. The results are usually painful (like kissing the handlebars), and drivetrains are alot cheaper than dental work.

Good riding.

Thanks, Walt.
I'm a heavy rider too. So my mileage would probably be similar to yours.

I'm going to have the LBS replace the drivetrain soon, but when I do, I'll get a gauge and an extra chain so that I'll be ready to change the chain when it shows ware. (I live far from the LBS).

Something else about Sachs/Sram chains, they seem to cause less of a skipping problem on worn cogs than other brands. I don't know wny this is, but my own and my customers' experience confirms it.

I've had about 2500-3000 miles on a new set of chainrings, rear block and chain, but now the chain is comprehensively knackered and the middle 3 cogs on the block likewise. Chainrings look ok though.

I'll struggle on to the end of this mucky Scottish winter before replacing.