schonnk

Hello,

I'm thinking about replacing my chain because I've been experiencing some grinding that I'm pretty sure is the result of chain wear. Do I need to replace the chainring and rear cog along with the chain as well? Will the new chain be compatible with the old cogs?

Mikefule

First, check that your existing chain is clean and well lubricated, and that the chainring and sprocket are also clean. They can pick up road dust and grime which mixes with the lubricant and creates a paste that can make a grinding noise and cause wear. A good clean may get rid of the grinding noise.

Second, if you need to replace the chain, it does not mean that you automatically need to replace either the chainring, or the sprocket, or both. Look at them to see if they need replacing.

An aluminium chainring or sprocket will wear faster than a steel one.

Look at the teeth: are they still symmetrical, or have they started to to wear into hooks? If they have started to hook, then it is time to replace.

Chains are a routine item to replace; chainrings and sprockets less so.

commo_soulja

Invest in a $10 Park chain checker and check the wear in your chain. Cheaper to replace a worn chain than it is on a new cassette/chainrings.

schonnk

Great, thanks! This explains a lot. I do think my chain is pretty worn out, as I've cleaned it really well and lubricated it while the grinding still persists. I've peeked at my sprocket teeth and they look in fine shape, so I think I'll firstly replace the chain and see if that solves the problem.

seau grateau

In addition to above, make sure your chain isn't tight/binding anywhere in the rotation of the cranks. Tight chains are loud chains.

BicycleBicycle

Some say that you should do this because your chainring wears to your chain, and a new chain will also try to wear itself in in it's own way, but I personally think it's way overkill.
Can you imagine replacing $1-200 (or more) worth of parts everytime you change your chain?

Maybe in extreme circumstances you will have problems like chains coming off the drivetrain because it skips a tooth or something, but I think this is one of those things that only pros worry about when/if they're trying to get the smoothest possible drivetrain for whatever reason.

Cogs/Frewheels are almost always made of hardened steel (not always, i've snapped aluminum ones that I assumed were steel) so there won't be much wear there for the most part (check anyways).

Chainrings are made of aluminium so will definitely wear when rubbing against steel. I'd say it's only an issue if your chainring is already incredibly worn after like several years of use or a couple of months of really bad maintanence (you shoudl be cleaning and lubing your drivetrain often).
I'd change the chain, then just kinda be aware of it and a taad more careful while you break in the chain. If you're not skipping around or it doesn't have too much play, you're pretty much good to go.
And like the other poster said, check for "sharktooth" (sprocket teeth worn down and thin to the poitn of being sharp).
That's the only reason I've ever had that really justified replacing a chainring.

Philasteve

I went through like 5 chains before I replaced my cog and chainring. I'm not saying to do the same thing, but I feel like it answers the question of "Do you need to". And my drive chain wasn't overly loud at all, you might need to spend hundreds of dollars before you get a really quiet drive chain sometimes even really expensive components end up not being quiet. So it's up to you if it's worth it or not.

diff

If you can, replace all 3 together will be the most quiet drive train.

You don't have to. Depends how much noise you are willing to put up with, and the quality of the parts.

I have a bike where the chainring and chain have worn together for 2-3 years, and then a cog (surly cog which seem to already be loud) which came from another bike with 3-4 years wear. Loudest drive train ever. But works just fine.

Also if you ever have to rotofix something off, don't ride that chain.

When I do change the chain on my main ride, I change the cog too since its cheap. Have a tree lite sprocket on that one which is still looking good so haven't replaced it. Drivertrain is very quiet on this bike. I change the chain every 1-2 years. Usually when it starts to pop its times for a new one.

wphamilton

When the cog is worn it can be a little noisy with the new chain, but it quiets down after a little while. Go through several cogs, at least, before you need to replace the chain ring.

acir71

Apologies for bugging the thread; I was wondering whether its ok to have more than one link on the chain; the logic is to facilitate changing different cog / chainring sizes without having to cut the chain short via the pin or get a new longer chain for the purpose. Anyone been there? Tks

Philasteve

What do you mean by more than one link on the chain? I used to always have my wheel pretty far back in the drop outs so I could put a bigger cog on if I needed to in the winter time, doing so by just keeping an extra 2 links on from where I would usually cut the chain down at. As long as the axle nut is contacting all metal in your dropout and your wheel isn't going to fall out of your dropouts when you tension your chain it's fine to have a little extra chain. If that's what you're talking about.

acir71

Sorry I meant to say 'having more than one master link / removable pin'. I read somewhere that having more than one of those just increases the possibility of the chain failing while skidding - I don't think it's a strong argument but just wondering if anyone has an experience with those.

ThermionicScott 

How many different gear combinations do you plan to run? I switch my bike between 45/16 and 42/18, depending on the season. That lets me just run the same chain length year 'round.

acir71

I'm comfortable with 48/17 on normal commuting, but there is a hilly loop nearby my place that deserves a more serious attention so am thinking about trying 49/18 & maybe 44/17 (based on what I have lying around). The chainstay bridge on my frame is also limiting the prospect. If I finally decided to cut them out will probably start a new thread on my so call experiment

ThermionicScott 

A 48/18 would land right in between your proposed 49/18 and 44/17, gearing-wise. And it would only move your wheel forward by 1/8". Just a thought.

acir71

Thanks, but I am actually avoiding the low no. skid patches. Tires are quite costly over here . Oh I am brakeless

Philasteve

Yeah that's why I don't run a brakeless set up, a front brake is cheaper than new tires.

Mikefule

Not an argument that will ever be won. I would never ride on the road without brakes, and I stopped skidding when I started paying for my own tyres. However, those who prefer to ride brakeless will continue to do so. Me: I have brakes but mainly control the speed by anticipating the road ahead, and back pressure on the pedals, but the brakes are there when the unexpected happens or when a downhill gets too steep.

BicycleBicycle

Believe it or not, I've actually been in situations where using the brake in an emergency was worse than if I had no brake at all.
You're not as effective at much of anything when you are suddenly frightened, and it really just mostly comes down to muscle memory in the worst situations.
If you're lucky, and it's a semi-familiar situation or you have just learned to relax really well (or you'r'e zoned out and similarly ineffective but at least you're relaxed), you can think through the problem.
I have had several incidents where quickly slamming on the brake injured me (one did permanent damage), and one other time I went headfirst into a truck.

The few times I had "close calls" while brakeless, I felt it was more natural to be brakeless because it takes so much force to stop, so all of your "panic motion" goes into skidding and once you're past that initial motion you're able to think and maneuver. The amount of force required to skid and be stable is more proportional to how you feel at that moment, which results in a smoother stop.

I've also been in situations where I wish I had a brake and being brakeless was not a good option.

You would be surprised at just how effective you can be if you're brakeless and you've gotten really good at it. I got to a point where only extremely rare and oddball situations would have been more effective with a brake (those things wouldn't happen very often normally).

Again, I haven't tried discs yet and I am yearning to try them because they seem to be that missing link between being able to go really fast and not worry about how you're going to stop.