Sram GX / XO1 / XX1 12 Speed mileage

[Christofison]

Im on my second chain on Eagle GX. First chain (lasted 1100km and measured 0.5% with Park Tool tool). Bought a XX1 Gold chain and have now done 7500 MORE KM and not close to 0.5%. Spending more on the bling chain is very worth it. Oh and same cassette. Been through 2 chainrings. I think Absolute Black and CSIXX Ovals dont last as long as OEM.....

I hope you're using a CC-4 or similar chain checker. The older & more basic chain checkers will be pretty inaccurate on XO1 & XX1 chains, with their over-sized rollers.

[love2fly]

I hope you're using a CC-4 or similar chain checker. The older & more basic chain checkers will be pretty inaccurate on XO1 & XX1 chains, with their over-sized rollers.

Used the 3.2 to determine old needs replacing ie 0.5 goes in easily....and that current is ok...0.5 won't go in probably not even with a hammer?

[Christofison]

Used the 3.2 to determine old needs replacing ie 0.5 goes in easily....and that current is ok...0.5 won't go in probably not even with a hammer?

So 0.5 on that older chain checker in an XO/XX1 chain, in reality is probably closer to 0.75% because of the larger rollers. 

[love2fly]

Thanks for the heads up. I'll try a different chain checker.

[love2fly]

But it's nowhere close to even thinking of going in. But will try nevertheless

[Christofison]

If you can be super accurate with a vernier on the side of the taught chain, then 12 half links should measure:
152.4mm = new
153.00mm ≈ 0.40% stretch

153.25mm ≈ 0.55% stretch
153.50mm ≈ 0.70% stretch

[DuncanCT]

Not sure if it has been discussed here before but it there any opinion about aluminum vs steel chain ring on longevity of the chain and cassette?

[love2fly]

If you can be super accurate with a vernier on the side of the taught chain, then 12 half links should measure:

152.4mm = new

153.00mm ≈ 0.40% stretch

153.25mm ≈ 0.55% stretch

153.50mm ≈ 0.70% stretch

I have a crappy vernier. Will buy a new checker tomorrow.

[SCD]

Not sure if it has been discussed here before but it there any opinion about aluminum vs steel chain ring on longevity of the chain and cassette?

 

The chain ring does not wear your chain. It is worn BY a stretched chain. Chains wear by abrasion between pins and inner chain plates, and abrasion of the inside of the rollers. This will increase the pitch of the chain causing force concentration on few or even just one tooth of the cassette or chainring. This will wear the tooth faces until the pitch of the teeth matches the chain again. If the teeth are hardened steel like high quality cassettes or your steel chainring they are more resilient and wear slower. But they WILL wear towards matching the chain.

I personally never wore an alloy chain ring so for me the steel option is not interesting.

Curious to hear if there are other benefits?

[love2fly]

The chain ring does not wear your chain. It is worn BY a stretched chain. Chains wear by abrasion between pins and inner chain plates, and abrasion of the inside of the rollers. This will increase the pitch of the chain causing force concentration on few or even just one tooth of the cassette or chainring. This will wear the tooth faces until the pitch of the teeth matches the chain again. If the teeth are hardened steel like high quality cassettes or your steel chainring they are more resilient and wear slower. But they WILL wear towards matching the chain.

I personally never wore an alloy chain ring so for me the steel option is not interesting.

Curious to hear if there are other benefits?

My experience is that on Narrow Wide setups the edges of the chain ring wear also from use of highly crossed over ratios like the 50 tooth on Sram 1x12

[DieselnDust]

Not sure if it has been discussed here before but it there any opinion about aluminum vs steel chain ring on longevity of the chain and cassette?

Most of the wear is at the high pressure interfaces. So that's the leading edge of the chain ring teeth, the trailing edge of the sprocket teeth and between the roller outer surface and the the inner surface and pin. Chainring and sprocket tooth wear will be induced by the roller sliding into the tooth before rolling occurs. The chain wears as a result of dirt and rolling as well as the side plates sliding over the inner plates.

 

Using a steel chainring has the advantage of reduced wear between gear tooth and chain under sliding. Hardness comes into play here.

 

The SRAM XX1 chains are coated. This coating gives the roller traction when it picks up the gear tooth on either side. With a steel chainring the traction is reduced when compared to the softer aluminum alloy chainrings. So sliding is more likely to occur with the steel rings.

That doesn't mean it will wear faster though since this is also dependant on the tooth profile.

 

Overall I would say its good to have a sacrificial gear in any open gearbox system. In industrial applications this is often the designed wear component or designed point of safety failure when wanting to prevent destruction of an entire gearbox in the event of overload.

 

So to answer your question... It depends.

 

I'd opt for the sacrificial chainring to protect the cassette and chain that are the more expensive components. The steel ring will likely last longer but then you'd be in for an entire drive train replacement and likely sooner if I apply industrial gearbox wear monitoring results to a bicycle drive train.

[love2fly]

If you can be super accurate with a vernier on the side of the taught chain, then 12 half links should measure:

152.4mm = new

153.00mm ≈ 0.40% stretch

153.25mm ≈ 0.55% stretch

153.50mm ≈ 0.70% stretch

My crappy vernier says 153mm...

[W@nted]

An update from my side. My gx eagle cassette is now on 5800km. Second gx eagle chain on 2700km now. This will be the last chain for this cassette as the new chain already slipped for about 300km. So I will ride this cassette and chain to their death before replacing with XX1

Interesting that with the second GX chain, I have only used Smoove chain cleaner and lube. The 0.5 wear indicator is not yet going in, so it seems that Smoove has given me some extra km on this chain. 

I tried a few different lubes on the first chain, and it was past 0.75 at 2500 km. Tried squirt and wend wax (wend wax the absolute worst wrt chain wear) on the first chain. Same riding conditions.

[DieselnDust]

1 hour ago, W@nted said:

An update from my side. My gx eagle cassette is now on 5800km. Second gx eagle chain on 2700km now. This will be the last chain for this cassette as the new chain already slipped for about 300km. So I will ride this cassette and chain to their death before replacing with XX1

Interesting that with the second GX chain, I have only used Smoove chain cleaner and lube. The 0.5 wear indicator is not yet going in, so it seems that Smoove has given me some extra km on this chain. 

I tried a few different lubes on the first chain, and it was past 0.75 at 2500 km. Tried squirt and wend wax (wend wax the absolute worst wrt chain wear) on the first chain. Same riding conditions.

The cassette is worn because of the chain that was run to 0.75%. Replace the chain before 0.5% wear and the cassette will last much longer

[W@nted]

10 minutes ago, DieselnDust said:

The cassette is worn because of the chain that was run to 0.75%. Replace the chain before 0.5% wear and the cassette will last much longer

Yip, definitely. Bought the bike second hand, the chain should have been replaced much earlier to save the cassette.

[Chain-L]

Have about 9 000km on a XO1 casette and XX1 chainring. I have been rotating three chains (2 x XO1 chains and one GX chain-which I took out of rotation, because of higher wear). I have now had a few chain drops and I am thinking of only replacing the chainring and see if that solves the problem. Should I consider getting two new XX1/XO1 chains to start with the new chainring and hope the casette is still ok, or do I just continue with the current 2x chains till the casette needs replacing?

I guess it will probably depend on the wear on the chains....and If they are still within the 0.5% then replacing with two new ones should be ok, if over 0.5 then probably to late..?
Would you agree with my logic and which DM chainring would you suggest?

Edited August 27, 2021 by Chain-L