Do 1/8" chains last longer?

[Dan B]

I decided at the weekend that my chain was long overdue for a clean, and after five minutes with a small bottle of oil and a clean rag, realised that it wasn't just dirty it was worn - as in, I could pull the chain away from the chainring and see daylight through the gap.

From looking at the purchase receipt I guess I fitted it last October so it must have done about 1500-2000 miles - in all weathers through a London winter. Sounds about typical?

 

[Deleted member 1258]

I decided at the weekend that my chain was long overdue for a clean, and after five minutes with a small bottle of oil and a clean rag, realised that it wasn't just dirty it was worn - as in, I could pull the chain away from the chainring and see daylight through the gap.

From looking at the purchase receipt I guess I fitted it last October so it must have done about 1500-2000 miles - in all weathers through a London winter. Sounds about typical?

Chain life tends to vary a bit, 2000 miles does'nt sound bad, I change my chains every year, I usually get about 3000 miles out of the chain on my fixed.

 

[mjr]

I could pull the chain away from the chainring and see daylight through the gap.

Maybe I'm misunderstanding, but can't you always do that if there's slack in the return run? What do 12 whole links of chain under tension measure?

If it's more than 12⅛" then on a derailleur bike it'd all be junk already, so you might as well run it until it slips and then replace sprocket, chainring and chain. I'm not sure if it's different on FG/SS/HG. http://sheldonbrown.com/chain-life.html has another tip.

 

[Deleted member 1258]

Maybe I'm misunderstanding, but can't you always do that if there's slack in the return run? What do 12 whole links of chain under tension measure?

If it's more than 12⅛" then on a derailleur bike it'd all be junk already, so you might as well run it until it slips and then replace sprocket, chainring and chain. I'm not sure if it's different on FG/SS/HG. http://sheldonbrown.com/chain-life.html has another tip.

On a derailleur bike changing the chain every twelve months means I can get through three chains before I have to change the cassette, on a fixed the only time I left a chain on and rode it into the ground the chain eventually broke, fortunately at low speed. On the fixed I change the cog and chain ring about every two years, with regularly changing the chain this keeps the transmission in reasonable condition, I really don't like to take chances with the transmission on a fixed.

 

[mjr]

Yes, good point, a slip on FG is probably much more probably harmful than on SS/HG

 

[fossyant]

I get 12 months of a daily commute out of a chain and sprocket, although I recon I'll need to change chains every 6 months on the new commute as the shared path is pretty filthy in the wet. Sprockets still every year and chain rings usually last 4 years

 

[Ian H]

All other things being equal, an 1/8th chain, being bushed, should last longer than a deraiileur, bushless chain.

 

[MrGrumpy]

up-til now a new chain at least twice a year, however I could probably use the same chain all year but then have to change chain, sprocket and front ring at the same time. However just changed my ratio so waiting to see how this wears in ? Been falling out of love with my fixed and think this maybe the year I buy a CX for winter/wet duties

So in reality a chain lasts me max 2000 miles

 

[Smurfy]

All other things being equal, an 1/8th chain, being bushed, should last longer than a deraiileur, bushless chain.

In my experience not all the 1/8 chains available are bushed.

 

[tyred]

In my experience not all the 1/8 chains available are bushed.

Unless you've found someone selling NOS, there is only one bushed 1/8" chain easily available to the best of my knowledge.

 

[Smurfy]

Unless you've found someone selling NOS, there is only one bushed 1/8" chain easily available to the best of my knowledge.

Izumi make at least one bushed chain, and I'd be surprised if they are the only manufacturer. Not all descriptions contain this information, sometimes you have to look closely at product photos and play spot the bushes, or lack of. Visually checking is not always possible, because you need to see the end of the unjoined chain.

 

[Profpointy]

Can anyone explain why a wider chain lasts longer? I assumed the side plates stretch or the rivet holes elongate rather than the rollers wearing - but now I think about it maybe it is the rollers that wear. Or are the side plates thicker on the wider chain. I know heavy duty chains for driving camshafts and the like can be duplex or triplex, which suggests that the side plates are issue. Is there an engineer in the room?

 

[mjr]

I'm not this sort of engineer but I think spreading the load over an extra 1/32" width and not twisting it this way and that so often (like you do a derailleur chain - this is why straight chainlines are desired) both should help reduce wear.

 

[Smurfy]

Can anyone explain why a wider chain lasts longer? I assumed the side plates stretch or the rivet holes elongate rather than the rollers wearing - but now I think about it maybe it is the rollers that wear. Or are the side plates thicker on the wider chain. I know heavy duty chains for driving camshafts and the like can be duplex or triplex, which suggests that the side plates are issue. Is there an engineer in the room?

In bushed chains, the chain elongates via pin wear and bush wear. In bushless chains, the chain elongates via pin wear and wear of the inner side plates where the pin passes through (the inner side plate is formed to accept the pin, support the roller, and remove the need for a bush, try dismantling a chain and you will see this).

There are various factors.

1. More side plates (triplex) means that the unsupported length of the pins is lower, so the pins will not bend so easily. Think of it like adding a bracket to the middle of a shelf, because the shelf has only two brackets, and is sagging in the middle.

2. Bushed chains ought to last longer, because the bush maximises contact/wear area, rather than allowing for flexing and twisting to permit deraileur gear changes (dismantle a bushless chain, and you will see that the area provided for wear via the formed side plates is inferior to a bushed chain)..

3. Increasing from 3/32 to 1/8 should extend life of sprocket and chainring due to greater contact/wear area.

4. Thicker outer sideplates will support the ends of the pins better, and reduce the risk of the chain breaking due to a pin being ripped from one side plate. Heavier chains often have very substantial riveting, which also reduces the risk of chain breakage.

 

[raleighnut]

Chains used to last longer before 'modern' manufacturing techniques took over, pins were hardened but nowadays pins are peened over/mushroomed after the sideplate, this could not be done with a hardened pin so of course they wear faster.