the 'there's no such thing as a stupid question' bike maintenance thread

How often should you change the chain? I'm up at 8000km on it and there's a bit of a miss when i pedal.

Google is telling me anytime between 3km and 8km.

magicbastarder wrote: »

probably shot if it's 8000km in unless you were using it primarily in dry weather and keeping it well lubed. if it's badly shot you may have worn out the cassette too.
you can get a chain wear checker in halfords for under a tenner.

Cheers MB.

Used in all sorts of weather over the last year. Got it serviced twice and cleaned too.

I'll bring it into the LBS this evening.

Type 17 wrote: »

It'll be badly shot if it's got 8000km on it - you may also need a front chainring or two.

It does depend on how many sprockets on your cassette - more means a thinner chain, which wears out faster.

My "good" bike has an 11-speed drivetrain which costs a bit to replace (Chainreaction lists the cassette and large chainring at around €180), so it's cheaper for me to change the chain early - here's my notes on chain replacements since I got the bike last July - I'm still on the (new-looking) original cassette and chainrings - (note how soft the Shimano original chain is):

Chain / km's done / wear when changed / (km's per chain) / Lube used
Shimano 8000: 0-250 -0.60% (250km) MucOff Hydro Dynamic
SRAM 1130: 250-1,200 -0.55% (950km) MucOff Hydro Dynamic
SRAM 1170: 1,200-2,200 -0.60% (1,000km) MucOff Hydro Dynamic
SRAM 1130: 2,200-3,330 -0.60% (1,130km) Smoove Universal
SRAM 1170: 3,330-

You have my mind made up on ever going 11 speed!

How are you measuring wear? A lot of those chain tools overestimate.

Attached is a 10 speed tiagra crankset with 50k km or so. 34 is original and 50 is still good but removed when I moved to its 3rd bike at put on a 42.

Chains lasted a minimum of 5k and up to 9k.

As you can see I'm not too fussy with cleanliness although chain in photo is lubed.

That's like someone had a dirty protest on your bike!!! :eek:

Large bottle small glass wrote: »

How are you measuring wear? A lot of those chain tools overestimate.

I'm using a Park Tool CC2. I measure different parts of the chain for an average and avoid the speedlink in the measurement. Seems to agree with all of the other tools I've tried.

Large bottle small glass wrote: »

Attached is a 10 speed tiagra crankset with 50k km or so. 34 is original and 50 is still good but removed when I moved to its 3rd bike at put on a 42.

Chains lasted a minimum of 5k and up to 9k.

As you can see I'm not too fussy with cleanliness although chain in photo is lubed.

10-speed stuff does last longer, and you've been diligent in changing the chains in time. I am probably being over-cautious, but service info is that the finer the chain (the more speeds), the earlier you should change it - from trying customer's bikes after fitting a new chain and then checking for skipping (because they'd rather not buy a new cassette), I'd say that you can get away with letting 5/6/7/8-speed stuff wear to about or just over 1%, 9 & 10-speed to just under 1% and 11-speed to about .75%. Over those amounts, skipping is much more likely, especially if you've used one or two of the sprockets a lot (especially the smaller ones).

However, worn cassettes/chainrings that don't skip with a new chain will still wear that new chain faster, because less teeth are actually meshing with the chain, so the links that are meshing get a higher load. Here's an (extreme :eek:) example (late 80's bike in in 2017 on original Biopace chainrings and presumably the original chain) - note how only a few links at the bottom are still meshing at all* - a new chain and sprocket will mesh almost all the way around. In less extreme situations, you may not get as many kms from a new chain because of this.



*The chain was skipping (no kidding!) and the whole bike was in similar condition, so I recommended that it was time for a new bike

Type 17 wrote: »

I've heard good things about them too, so I must give them a go.

And the gold chain looks brilliant. I'm looking forward to seeing what it's like on the darker bike

Type 17 wrote: »

That's my drivetrain too - any experience (yet) on how the 11-speed KMC lasts? (looks good though )

Unfortunately that bike died a few days after that pic was taken. I have the Di2 bits ready to go on to the new bike now (I bought this as replacement)

That drivetrain is all R8000 apart from the cranks, I have since bought the R8000 cranks though to go onto the Look.

magicbastarder wrote: »

probably shot if it's 8000km in unless you were using it primarily in dry weather and keeping it well lubed. if it's badly shot you may have worn out the cassette too.
you can get a chain wear checker in halfords for under a tenner.

Yer man in the shop said I need a new cassette too. Is that legit?

You have to base it on what you can measure/see - based on the chain-wear measured on the checker, I confirm to them that they'll definitely need a new cassette because it will skip, or (if the wear is less severe) that it might skip, but will probably wear the new chain sooner, but even then, many people just want a non-skipping drivetrain and don't care that they'll need another new chain sooner...

Anybody know or have experience of using Sram Force 22 calipers with Ultegra Levers (R8000)

Not a permanent solution but just for a couple of weeks

LollipopJimmy wrote: »

Anybody know or have experience of using Sram Force 22 calipers with Ultegra Levers (R8000)

Not a permanent solution but just for a couple of weeks

Scratch that, I have 6800 I can use until I get the 8000

I got new mudguards for my commuter - have been using clip ons so don't know much about mudguards and just went for the ones that the bike is originally sold with (SKS Bluemels - the bike is a Canyon Urban).

Looking at the tyres when I went to install, they say 650b but the mudguards are 28" and the web page says for 700c. Is there any possibility these will fit or am I better off not even opening them? (Although difficult to find a box to return them in)

doozerie wrote: »

28" is typically used in reference to 700c wheels. I gather that "real" 28" wheels exist, or existed in the past, which are a slightly different size to 700c wheels, but I believe they are essentially a niche product and might not even be available any longer.

650b rims are a smaller diameter than 700c rims, but the difference is relatively small and once you add large volume tyres then the diameter of a 650b rim plus large volume tyre can be the same as 700c rim plus low volume tyre.

So 700c mudguards should work with 650b wheels from that perspective, but mudguards usually have a width limit too, so you'd need to ensure that your new mudguards can handle the width of tyre you are using or plan to use in the future.

Thanks, I'll give them a try so