Signs of wear and tear that mean time to replace parts....

[Chap sur le velo]

Lets start with the obvious, but feel free to add more.

Brake Pads. I started to ride seriously in May and in August I changed the front pads as they were loosing the separate bits of the block ( but some definition, maybe 0.5mm remained). I was amazed by how much stopping power the new pads added. Perhaps because the old ones were 7 years old?

Chains. I understand there's a measuring tool for stretch? Does everyone need one? Obviously it "all depends" on how hard you ride it, but after how many km (a range is a good answer) do I need to measure wear?

Tyres. How big a scratch or notch can be ignored? On the 23mm tyres I have the central section seems 'slick' and the tread is to The sides, so how evaluate wear? Milage? Age? Also is it customary to change inner tube at same time?

Cables, Seat and....

Apologies if this has all been gathered together before. please link to thread...

 

[fossyant]

Tyres usually square off, so time to replace if a slick type - you can tell on my MTB when they wear - lost half the knobbles this year as lots more riding, but the new tyre is on for winter, and the old one will go back on in the dry.

Chains - you can use a tool (I have one) but how long they last depends upon use and how well looked after.

Cassettes can get shark toothed, as can chain rings, although the chain ring on my full suspension has 'thin' teeth now due to lots of use this year - only 12 months old - not shark toothed, but going thin, and affecting shift. Not really a problem on road bikes as much, as the grit and mud has worn them on my MTB.

Cables - when gears don't work as well as they should or brakes feel rough.

 

[PaulSB]

Check your chain for wear by selecting gears to put the chain on the big ring and smallest cog on the cassette.

In the middle of the chainring pull the chain towards the front wheel. If the chain lifts off the teeth it's time for a new chain. You can't simply go on mileage as there are too many variables.

You suggest the bike is seven years old and possibly has had little attention. You may need to replace the cassette and chain rings as well.

Cables would be changed when shifting/braking issues can't be addressed by adjustment.

Tyres can't be calculated on mileage either. Close inspection will determine if they're good or not.

 

[Chap sur le velo]

Thanks for taking the time to reply and please don't think I'm trying to be difficult when I ask for the answers to be taken down a notch or 3 to cater for a beginner like me. If I knew what a sharks tooth cassette looked like I wouldn't have to ask my dumb questions. Also what wear makes a tyre good or bad? I know it's hard to be specific, but you guys don't seem to realise how much we beginners have to learn. Help is appreciated.

 

[Ajax Bay]

Chains
Chains don't stretch they elongate: the pins connecting the link plates wear. If you let the chain elongate more than 0.75% then you cause increased wear to the cassette's sprocket teeth, so two options: change it before it reaches there OR ride on and let the chain and cassette wear together, until the chain skates. Some people find their cassette 'last' 3 chains using the former option and for 10 or 11 speed drivetrains, it's economically worth it (because the cassettes are significantly more expensive than 9sp and lower).
One can't tell by looking at the sprockets whether they are excessively worn. And the chain will skate on the most well used sprockets well before anything is visible. Mileages, which the OP asks for, varies with type of riding, chain maintenance regime but I expect to get 2000km per chain. If I miss the 0.75% point then the chain and cassette will give me about 5000+ km. When the chain starts skating under power it's time to change both at the same time. Use a metal rule to measure at least 10 inch links of the top section of the chain (under mild tension). Each inch link will measure 25.4mm (surprise!) and maths will allow the percentage elongation to be calculated.
Tyres.
Milage or age? Do it on mileage. This so depends on use and the nature of the rider's roads, and the make/model of tyre. I expect to get 8000km for a front tyre and 5000km on the rear - Conti GP 4 Seasons (and typical of others) for me. NB long distance rural cycling.
change inner tube at same time?
No rationale for so doing.
Cables
Inspect brake cables and if there are any broken strands at the clamp point, replace. (Assume these brakes are calipers (ie not disc brakes).)
Change gear cables annually. Worth replacing the rear gear cable outers at the same time, in particular the loop going from the chainstay round to the rear mech.
Seat
Remove every 6 months, clean the seat post, grease and refit.

 

[Lovacott]

Chains
Chains don't stretch they elongate: the pins connecting the link plates wear. If you let the chain elongate more than 0.75% then you cause increased wear to the cassette's sprocket teeth

I'm trying to measure chain wear with a bit of wire coat hanger.

When I fitted my last new chain back in the summer, I got a piece of coat hanger wire and cut it so that it was exactly the length from one pin to 20 pins back with the chain taut (measured from pin centre to pin centre). Last check (a week ago), there was just over a millimetre of elongation in the 20 links which equates to around 0.45%.

When I did the last chain swap (long overdue), I put the old and new side by side (rather than counting links) and once lined up, the old chain was a good two links length elongated (the bike was practically unrideable by this stage).

I have three chain rings and seven sprockets (21 speed) and the easy way to tell if the chain is on its way out is to try going up an incline on the smallest chain ring and smallest sprocket. The chain will skip.

My chains only cost a tenner so I'm slapping on a new one tomorrow morning. Once you've done it the first time and learned the process, it's literally a 15 minute job.

 

[Ajax Bay]

I'm trying to measure chain wear with a bit of wire coat hanger.
cut so that it was exactly the length from one pin to 20 pins back with the chain taut . . . there was just over a millimetre of elongation in the 20 links . . .

254mm long, then. How did you cut it to exactly the correct length?
How did you measure how much elongation there was, or did you estimate 'just more' than 1mm? Personally I have an 18" steel rule, and a better physical point of measurement is to two corresponding ends of an outside chain link: that avoids one having to estimate the pin centre in two links 255mm apart (which risks parallax error).

When . . . I put the old and new side by side . . . the old chain was a good two links length elongated (the bike was practically unrideable by this stage).

Given your chain was about 57 inch links long (you are describing a link as a half inch), the new chain would be about 1447mm long. "A good two links would be 25mm: that's 1.7% elongation. I'm amazed that the chain wasn't skating/slipping all over the place before that time. I'd further observe that if a rider let's their chain go that far, there'll be accelerated wear on all the chainrings. Stand by to suck.

My chains only cost a tenner so I'm slapping on a new one tomorrow morning. Once you've done it the first time and learned the process, it's literally a 15 minute job.

If a rider has left this chain replacement beyond 0.75% elongation on the current chain, they'd be prudent to have a new cassette/freewheel block 'in the spares box' ready to fit. Once the new chain is fitted, test it straight away, to check whether it skates/slips or not. Top tip: Don't throw away the old chain. If the new chain skates/slips on the old cassette, replace the old chain, and ride on. Then replace both cassette and chain together, a thousand miles or more later.
https://www.sheldonbrown.com/chain-wear.html

 

[Eribiste]

Something else to give a bit of thought to when doing a bit of deep chain/cassette cleaning or overhaul is the condition of the bearings that support the crank in the frame. My roadie had done about 3000 miles when I changed the chain (a bit overdue to be honest). With the chain off, I gave the cranks a twirl and found a fair bit of graunchy feeling and noise. This is masked when the bike is intact because of the connection between chain, chain rings and cassette. Bottom bracket dismantled and new bearings fitted and bliss, silent running!
Next chain renewal will be the expensive one where the chain rings and cassette get swapped out too. I'm starting a saving fund now.

 

[Will Spin]

If you've got rim brakes and you ride a lot in hilly country in wet weather it's a good idea to check the rims for wear, light weight wheel rims have surprisingly short life spans in those conditions!

 

[Lovacott]

Given your chain was about 57 inch links long (you are describing a link as a half inch), the new chain would be about 1447mm long. "A good two links would be 25mm: that's 1.7% elongation. I'm amazed that the chain wasn't skating/slipping all over the place before that time. I'd further observe that if a rider let's their chain go that far, there'll be accelerated wear on all the chainrings. Stand by to suck.

I'd been riding the MTB casually for about five years and started to hit it hard in March during lockdown.

Never did a thing to it apart from put some air into the tyres.

By around mid June, I started to suffer badly with chain slip whenever using smaller sprockets on the back under load (hills).

I tried re-indexing, cleaning, oiling and so on until I gave up and replaced the entire drive train. It was at this point, when replacing the chain and following the "side by side" link counting method, that I realised that my old chain had stretched pretty significantly.

I devised the coat hanger wire measuring method pretty much off the cuff, mainly because I didn't want to leave it too long before changing chains next time around.

I've now bought a chain checker from Park tool which is due to arrive tomorrow to add to my chain splitter, crank remover, bottom bracket tool, freewheel tool and all of the other stuff I've spent a fortune on in the last nine months trying to keep my bike on the road.

 

[Blue Hills]

If you've got rim brakes and you ride a lot in hilly country in wet weather it's a good idea to check the rims for wear, light weight wheel rims have surprisingly short life spans in those conditions!

increasingly true I fear with many rims, as I gather, getting thinner.

 

[Blue Hills]

Keep your wheel bearings sorted.
I ignored them for years, but not so complicated once you get down to it.
Properly maintained shimano ball bearing hubs will last for donkey's years if maintained.

 

[Lovacott]

I've now bought a chain checker from Park tool which is due to arrive tomorrow to add to my chain splitter, crank remover, bottom bracket tool, freewheel tool and all of the other stuff I've spent a fortune on in the last nine months trying to keep my bike on the road.

Used the chain wear tool on my chain and it slips in with ease on the 1% mark so I'm now going to be fitting a new freewheel at the weekend to go with the new chain I've just fitted. The existing freewheel with the new chain seems fine but for the sake of £23, I'm going to change it anyway.

I've also bought a spare chain so that I can swap out as soon as the current one gets at or near .75%.

Simple little bit of kit is the old chain checker. Everyone should have one.

 

[Chap sur le velo]

Thanks for all the responses, will be having a good look over when I clean the bike Sunday. For other beginners there's Also interesting comments in thread below.

https://www.cyclechat.net/threads/road-bike-service-intervals.269135/


Still not sure what a worn tyre looks like? Car tyres have depth wear indicators but bikes are based on impressions.

Finally I saw another thread that strongly suggests at least an annual check of your favourite stretch lycra shorts. Think of the poor cyclists behind you...no one wants to see that!

 

[Lovacott]

Still not sure what a worn tyre looks like? Car tyres have depth wear indicators but bikes are based on impressions.

Tyre tread depth is critical on a car due to the risk of aquaplaning on wet roads. Treads are designed to chase away water and maximise road contact. On a bike, the point loading alone is enough to minimise this risk.

I've kept tyres going to the point where I can actually see the inner tube through the wear and I've never come to grief through lack of grip.

Good practice though is to buy one or two spare tyres and swap them out as and when needed whilst doing something else which requires wheel removal. Having a new spare tyre also gives you something to compare your old tyres against.