Hmm. 5000 miles is 8000km. Neil also tells us "I don't run a Chainglider although I am a spinner rather than a masher which probably helps" and that the chain was not yet "stretched" to 0.75. And George tells us that his 48 inch steel rule says the short chaincheckers overestimate wear. Let's therefore guesstimate that Neil's X1 could have gone to 10K in kilometres at the chainchecker's (overconservative) suggested limit.
As it stands, I'm not overly impressed with the X1. SJS prices, STG:
KMC X1 £36
KMC X8-93 £8
KMC X8-99 £19
The Z8 RB -- which is a singlespeed chain whereas the X8 though commonly used as a Rohloff chain is actually a derailleur chain -- is comparable to the X8-99 in rustproofing, but at little more cost than the X8-93; not stocked by SJS or almost anyone else British because the X8 is so famously good for single-speeds as well, but let's call it, following German examples, about £10.
I'm a masher, which must be nasty for my chains, and given to running experiments, which isn't a featherbed for chains either. As expected, I therefore have a long history of being heavy on chains: in my Shimano HGB 8 speed days I went through an entire Nexus transmission of chain, crankset integrated with the chainring, and sprocket every thousand miles or 1600km.
But the X8/Z8 KMC chains lasted 4500km in my hands (under my size 12 feet!) before being replaced at 0.5 wear on the chain checker. This approximates Neil's replacement strategy, though, being a spinner, he'd probably do better with my chains and Chainglider than I do. Thus, at current SJS prices, the economy of these chains in actual use can be compared, on the understanding that those who try can do much better:
KMC X1 8000km/£36 = 2.2 kilometer per penny
KMC X8-93 4500/£8 = 5.6 kilometer per penny
KMC Z7 RB 4500/£10 = 4.5 kilometer per penny
KMC X8-99 4500/£19 = 2.36 kilometer per penny
Your mileage will definitely differ.
Clearly, looking at that table, the bargain is the KMC X8-93. For Chainglider users, even the 25% premium for the Z7 RB isn't worth it. For those with open chains who like a shiny bright chain, the bargain is the Z7 and it is worth hunting down as being twice as economical as the X8-99.
Until someone positively demonstrates that the X1 does better than the cheap X8/Z7, Neil's experience proves that the X1 doesn't cut it to anywhere near the extent it's elevated price might suggest.
I'm keenly looking forward to Neil's experience with the second X1, because it has at least one advantage: to those of us who're not too keen on getting our hands dirty (I'm not embarrassed by it at all -- a writer and painter's hands are to him like a surgeon's hands, his entire fortune), or who for one reason or another must restrict time spent bending over bike, and especially to those of us prepared to trade in money for extra-low maintenance, the KMC X1 does seem on Neil's experience to offer extended periods between changes. That by itself may be worth the premium. And Neil wouldn't have to extend his chain very far (less than 500 additional kilometres) to bring it even-steven with the all-shiny X8-99 which also has adherents here...
Much thanks to Neil for taking a hit in the wallet for the team.
***
It's worth keeping chains in perspective. We can get too competitive about chain mileage. (And I remind you that the once and always chain mileage champ is Stu, who used to be moderator before Dan.) The average annual depreciation on my bike -- any expensive bike like a Rohloff Thorn -- is about £200. My actual cost in chains in recent years has ranged from £2 to £10. Chains, as a cost factor, even at X1 prices, are a joke. It's what a bad chain takes with it, the chainring and the sprocket, and perhaps an expensive holiday ruined, the nuisance value in irritation of having to change poor-quality chains when the sun shines, that really matters.
