Chain Wear, On Disc-Braked Bikes

[Richard A Thackeray]

'Two Parter'

I bought my Ribble CGR, back in March
On Sunday, I replaced the chain (as a precaution/to save cassette/chain-ring wear)

I recall that the chains, on the 'blue' Ribble didn't last as long, & the cassette also needed replacement*
It had (I think) 4 chains & 2 cassettes, in 3 years I used it
It was my year round, as commuter/trainer/'do it all' bike (even out with local Triathlon Club on it)

The CGR's seen a lot more use, than the 'blue' did, as due to constant little aches/pains/'niggles', I've not run to work as much (I'll be lucky to run 1,000 miles this year)


It all seemed cleaner, less worn, no grittiness in the links
I'll conjecture, that as there's not the grime/brake-dust mixture falling onto the chain/cassette, from a standard caliper brake; be it dripping onto it, whilst riding, or if propped up at an angle which allowed it to drip onto chain
Therefore less wear!
Am I right??



Plus;
Still getting an odd noise from the front disc
The best description is, that it's like a freewheel ratchet

At first, I thought it was just the actual freehub resonating through the frame, as I braked - tightening up the forks/headset interface
But it still does it, if I'm pedalling

Shimano RS505 STI / Hydraulic Disc Brake Set w/RS785 Calipers
Clarks Dirt-Dissipation rotors

I did initially think it was a compatibility problem, but if it was I'd have the same problem with the rear, but that's fine



* No chain on it now, & it needs another new cassette (as it's just stood in a corner, since the CGR arrived)

 

[I like Skol]

Not a chance in hell that the brake type is affecting chain cleanliness/wear.

I have/had a similar noise from the disc brakes on one of my bikes under certain conditions (can't remember which one now which suggests it is my Grade as haven't ridden that one for a while due to warranty issues). I think it may be the pad catching the outer edge of the disc as these are never round and have what can best be described as a wobbly edge and cut outs in the braking surface too. It has never been overly intrusive or affected braking so after checking all was well I have chosen to ignore it (it may well have gone off in a huff because I didn't give it any attention ).

 

[Nigel-YZ1]

FWIW I only get the ratchet sound from my discs under prolonged braking when there's a lot of heat buildup. And that's coming down from 30mph+.
Wonder if it's a rubbing pad?

As for the chain wear being connected to disc use I don't have a clue. It's the opposite side so dust shouldn't get across

 

[Richard A Thackeray]

Not a chance in hell that the brake type is affecting chain cleanliness/wear.

I have/had a similar noise from the disc brakes on one of my bikes under certain conditions (can't remember which one now which suggests it is my Grade as haven't ridden that one for a while due to warranty issues). I think it may be the pad catching the outer edge of the disc as these are never round and have what can best be described as a wobbly edge and cut outs in the braking surface too. It has never been overly intrusive or affected braking so after checking all was well I have chosen to ignore it (it may well have gone off in a huff because I didn't give it any attention ).

Likewise, the action/effectiveness isn't compromised. It's just the annoying noise (not loud enough to be noticed in traffic)

Wonder if it's a rubbing pad?

As for the chain wear being connected to disc use I don't have a clue. It's the opposite side so dust shouldn't get across

Nothing to be heard, when spinning a wheel

It just seems a very logical reason for a decrease in chain-wear, given the higher mileage, & the 'grime' acting as an abrasive

 

[Andrew_P]

I tend to agree although have no fact to back it up. The only comment I will make is I felt that fitting mudguards to a calliper brake bike increased my wheel rim wear as well as the crap was dripping down over the rim as opposed to my backside. So I think it is fair to assume a fair bit of crap would be going over the chain from braking, but no solid evidence m'lud!

 

[pclay]

I assume you used a chain wear tool to determine that the chain on your CGR actually needed replacing?

 

[Ajax Bay]

I felt that fitting mudguards to a calliper brake bike increased my wheel rim wear as well as the crap was dripping down over the rim as opposed to my backside. So I think it is fair to assume a fair bit of crap would be going over the chain from braking,

The liquid finding itself inside the mudguard would migrate to to the edge of the mudguard and drop outside the line of the tyre/rim, not onto the rim, and inside the chainline (even when in lowest gear) (no solid evidence of this; just conjecture based on geometry and fluid dymnamics). So don't think your assumption is fair. The rims (particularly the rear one) get plenty of cr*p on them during a wet/dirty ride: but I suggest the proportion of that coming via the mudguards is low.

 

[Richard A Thackeray]

I assume you used a chain wear tool to determine that the chain on your CGR actually needed replacing?

No, just 'time served', in comparison to the 'blue' Ribble, that preceded it
I use the unscientific method of pulling it away from the chain-ring, as I have for 30 years
I try to change at set intervals, no Strava/no 'computer'/ etc....., just a reasonable idea of mileage covered (& what terrain; if a lot of hills)