Replacing Chain and chainset / cassette

[chris__P]

Hi all

Would appreciate any advice. I'm currently biking around the world on a Surly Long Haul Trucker. I have ridden about 14,000km so far without replacing any of the drivetrain components.

The chain needs replacing as it is stretched and skipping. The middle chainset has the most extraordinary sharks teeth and needs replacing. My question is, after this long, can I replace just these. Will the new chain run ok on the existing cassette, because the casstte is surprisingly unworn and I dont want to replace it unless I have to. If I dont replace it, will the new chain definitely skip on the old cassette?

 

[MikeMc]

Replace the cassette as well. Some of the cogs might be OK but the more heavily used will be worn and will skip.

 

[Fattman]

Hi all

Would appreciate any advice. I'm currently biking around the world on a Surly Long Haul Trucker. I have ridden about 14,000km so far without replacing any of the drivetrain components.

The chain needs replacing as it is stretched and skipping. The middle chainset has the most extraordinary sharks teeth and needs replacing. My question is, after this long, can I replace just these. Will the new chain run ok on the existing cassette, because the casstte is surprisingly unworn and I dont want to replace it unless I have to. If I dont replace it, will the new chain definitely skip on the old cassette?

Now there's an interesting reason for wearing out a drivetrain - better than simply grinding down the teeth on a dismal commute....

It sounds like you'd be advised to change the chain (dur, obviously), the cassette (+1 prev reply re. wearing out some sprockets and not others). I think you are specifically asking if you can get away with changing just the middle chainring (of a triple?) I would think this is not so clear-cut; chainrings (particularly the large one) do not wear as quickly as cassette sprockets (I believe because the load is distributed across more contact points) so it is possible the large is within tolerance... However... (things are never clear-cut, are they?) - it doesn't take much of a mismatch in the fit between chain and teeth to really accelerate wear of one or both components as the loading gets concentrated onto the reduced points of contact, which will then spread to the cassette and you're back to the start again.

In summary, I guess it's 'Yes' to chain & cassette and 'Probably' to the whole crankset, depending on budget, and then change your chain more often!

Good luck...

 

[MikeMc]

If the outer chainring is not worn then why not? It means that you are not using it and is probably too big. You might want to consider changing it to one that you will use more often. This will distribute the wear on the cassette rather than those cogs you use when in the middle ring/cruising speed cog combo. Given that a worn ring promotes wear in the rest of the drivetrain it's probably best you actively manage which ring gets the most use.

Have you considered changing to a Rohloff

 

[e-rider]

the cassette will definitiely need changing as they wear quicker than chainrings usually

 

[andy_wrx]

You've worn-out the middle chainring because you've mainly (almost exclusively ?) been running on it and very seldom in the big ring or granny ring ?

Then yes, by all means simply replace that ring and leave the other two alone.


And yes, if you've done that to the chainring then the chain will certainly be worn and need replacing, and having run a worn chain will have worn the cassette, certainly those cogs you use the most, so you'll need to be replacing the whole cassette too.

After 14000k, a chainring, a chain and a cassette - not anything to worry about, these are wearable-replaceable items and not a lot of cost for that sort of mileage.

 

[2Loose]

After 14000k, a chainring, a chain and a cassette - not anything to worry about, these are wearable-replaceable items and not a lot of cost for that sort of mileage.

Very well done! I needed to replace the whole lot after 6k, so to do the same after 14k is amazing (and also qudos to you for mechanical respect

).

Next time change the chain more frequently and save wear on the cassette and chain rings in the process.