Thorn Cycles Forum
Community => Rohloff Internal Hub Gears => Topic started by: Chris2020 on May 02, 2026, 11:18:54 AM
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Hello,
I’m a 1st time Rohloff owner. Thorn nomad mk3
5 years old 22000km
Minimal maintenance other than yearly oil change and very occasional cleaning and oiling. No chainglider
EBB at max adjustments. Ie.
chain at the pont when I would need remove links.
I am wondering when would be the point to either replace the chain, replace or flip the chainring and/or sprocket?
Any advice would be much appreciated.
Thanks
Chris
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I take it from what you say that the slack in the chain has already reached the point where adjustment is necessary but there’s no adjustment remaining on the eccentric.
Rohloff recommend a new chain is fitted after reversing a sprocket.
I don’t know how successful taking a link out of the chain would be because I’ve never done it. If it was me I’d simply flip the sprocket, and the chainring, then fit a new chain.
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I think that with a straight chainline then the chain can be fairly slack without the risk of it coming off. However, if it's a long time since the chain was last replaced then I would first replace the chain (single speed chains are reasonably priced) and see how will it runs. If it isn't happy then flip the sprocket and chainring.
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I take it from what you say that the slack in the chain has already reached the point where adjustment is necessary but there’s no adjustment remaining on the eccentric.
Yes, and it's come off a couple of times now. The chain has never been replaced. I did buy a replacement at some point but haven't swapped it yet, but from what I understand now would be the time to do so.
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You might eek out another few thousand km's by taking a link out, but the failure method becomes more and more likely to be a snapped chain. I'd consider I'd had good value from it. flip both chainring and sprocket and fit the new chain. I don't always get the same distance out of the second side of a chainring and sprockets, maybe 70%, but yours don't look as worn mine usually do at that mileage. Even at 70% that's nearly 40k km from a chainring, sprocket and two chains, that'll turn most people running a derailleur green with envy.
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Thank for your reply. That is kind of the feeling I had but as I’ve never been at this point before, part of me does want to see how long I can get out of one chain. As you say compared to my previous derailleur bike it’s really hard to fathom!
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You might eek out another few thousand km's by taking a link out, but the failure method becomes more and more likely to be a snapped chain. I'd consider I'd had good value from it. flip both chainring and sprocket and fit the new chain.
Agree. After 22000 km and given the wear on the chainring, time for a new chain and flip the sprocket and chainring.
Snapping a chain could be very inconvenient.
On a hub gear bike I have had this happen once, the outer plates on one link failed on a very worn chain, but nothing like 22000 kms use. This was before I started using Chaingliders, which make a significant difference to transmission maintenance and longevity, at least for all-weather use in the coastal area where I live.
Fortunately for me I was only a few kms from home and the bike trailer I was towing had been unloaded before the chain broke. So not too hard to push the bike/trailer up the hills and coast on the downhills. My bike toolkit now includes spare 1/8" chain links in addition to the 3/32" quick links and spare links I already had.
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Strange how the chainwheel is more worn than the sprocket - but maybe it is alloy while the sprocket is steel?
With teeth starting to hook is there a risk of the chain being sucked up the back of the chainwheel and locking up?
Out of interest, what make /model of chain is it? I think Thorn used to fit KMC X1 chains which have a good reputation for long life but were not cheap.
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Strange how the chainwheel is more worn than the sprocket - but maybe it is alloy while the sprocket is steel?
If it's the original chainring supplied by Thorn it is almost certainly aluminium alloy.
With teeth starting to hook is there a risk of the chain being sucked up the back of the chainwheel and locking up?
Very unlikely on hub gear without a derailleur or derailleur type tensioner. Even with a slack chain, though with the latter it can drop off the chainring.
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The chain is KMC E1, original chainring supplied by Thorn 45T and sprocket is rohloff (steel) 19T.
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Put on a new chain, flip the sprocket. Your sprocket looks amazingly good for that distance and if your chain is worn. My sprocket was more worn than that when I finally flipped it.
Your chainring looks more worn than the sprocket does, that surprises me. I would replace the sprocket chainring at this time.
You might consider measuring your chain later. The cheap small chain checkers are not very accurate, but you can measure the length of an entire chain when it hangs from a hook. One link is a half inch when new, thus 100 links is 50 inches from center of pin to center of pin. If it is 50.5 inches, that is one percent elongation. I think on a Rohloff bike replacing the chain when you are a bit over one percent elongation is a good time to replace it.
EDIT: I made a correction above, I meant to suggest replacing the chainring, but used the word sprocket inadvertently.
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The KMC E1 is reputed to be a good chain but not cheap. It looks like it has done well. Perhaps helped by your 45 / 19 ratio?
The chainwheel being alloy probably explains the wear - but if you can flip it then it will also do a good total mileage.
If you fit a new E1 and flip both chainwheel and sprocket then in another 22,000 km everything will be due for a change.
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The KMC E1 is reputed to be a good chain but not cheap.
I use these for most of the hub gear bikes I maintain. With ChainGliders if possible. My take on this is that the higher price over a standard chain is compensated by longer chainring life (except for Rohloff the costs of rear sprockets are cheap enough to be ignored). Plus less time spent on chain maintenance.
Perhaps helped by your 45 / 19 ratio?
Big chainrings and rear sprockets wear less than small ones. On my Rohloff equipped large-wheel bikes, I have a 19T on my Raven Sport Tour and a 21T on my Raven Tour. I have 22T on nearly all the other hub gear bikes I maintain.
On small-wheel bikes that generally use 11T to 13T smallest sprockets I found wear was significantly less with slightly larger ones. My Rohloff equipped Brompton therefore has a 15T instead of the 13T usually fitted for small wheel bikes. On this bike another advantage is that the 15T can be flipped to get about double the mileage, whereas the 13T can't be flipped.
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The KMC E1 is reputed to be a good chain but not cheap.
I use these for most of the hub gear bikes I maintain. With ChainGliders if possible. My take on this is that the higher price over a standard chain is compensated by longer chainring life (except for Rohloff the costs of rear sprockets are cheap enough to be ignored). Plus less time spent on chain maintenance.
With Rohloff / chainglider I am using cheap chains - Sram PC870. £15 at Halfords. It is what was fitted on the bike when new and I now use two PC870 chains which I swop around every 5000 miles……it will take me a few years to wear them both out as their projected life looks around 15,000 miles each……they may outlast me.
Without a chainglider I would definitely fit a better quality chain - like a KMC E1 EPT. (AFAIK the EPT bit just means it has better rust protection). £30 at Halfords.
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The green glow around me isn't Spring bursting out in my study, it is envy of someone who gets 22,000km on a chain.
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Would 13670.2 miles be any easier……😄
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I'm a masher fallen among butterflies spinning an unearthly cadence. Before I went to Rohloff, stainless steel chainrings and the Chainglider, I was lucky if I got a thousand miles on a chain. So you don't just need to convert Chris the OP's sterling achievement to miles, you further want to divide by 13.67. Though thanks for the thought.
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You might consider measuring your chain later. The cheap small chain checkers are not very accurate, but you can measure the length of an entire chain when it hangs from a hook. One link is a half inch when new, thus 100 links is 50 inches from center of pin to center of pin. If it is 50.5 inches, that is one percent elongation. I think on a Rohloff bike replacing the chain when you are a bit over one percent elongation is a good time to replace it.
At 1% elongation how many chains would have been used by now? Three at least, possibly four? What makes financial sense on a derailleur doesn't transfer to a single chainline. Chris has saved the cost of three chains for the cost of 50% of a sprocket and chainring.
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The KMC E1 is reputed to be a good chain but not cheap. It looks like it has done well. Perhaps helped by your 45 / 19 ratio?
The chainwheel being alloy probably explains the wear - but if you can flip it then it will also do a good total mileage.
If you fit a new E1 and flip both chainwheel and sprocket then in another 22,000 km everything will be due for a change.
I'm on the same chain, similar ratios, get the same sort of distance, never less than 20,000 km, over 25k a couple of times, haven't pushed my luck to 30k yet. Always flip both together, then there's nothing to change mid cycle.
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In theory, with a single-speed bike, like the majority of modern hub gear bikes and virtually all Rohloff-equipped bikes, you can run a transmission set of the chainring, sprocket and chain into the ground until the first of them breaks, then replace them all at once. The benefit of this method is supposed to be that the components will all have worn together and thus fit together optimally for their state of wear until the end, the expectation being that this method would deliver the greatest possible mileage from the set and, as a bonus, avoid fitting a new chain to worn teeth, which will ensure that the new chain gets to only half the mileage of a chain fitted to new teeth or reversed gears.
"In theory" means I haven't tried it, among other reasons because the underlying assumption above is that all the components have roughly similar lifespans, which just isn't true on my bike, where the Surly stainless steel chainring will very likely have a service life in excess of a magnitude larger than the KMC X8 chains I use, and the Rohloff sprocket will have a lifespan at least 5x the chain life; in all of this the qualification is "in my zero maintenance paradigm, in which I run the chain for its entire life (to half-a-percent wear at which point, at about 4500km, I chuck it off at the Rohloff oil change) on the factory lube with nothing added, inside a Chainglider". Note also another assumption, that there is a whole link-and-a-bit chain adjustment length built into the bike, which isn't true of eccentric bottom bracket adjusters as fitted to Thorn bikes, or even on most bikes with track (slotted) frame ends at the rear of the bike, though Rohloff's own "slider" axle hangers (for which they'll give OEMs blueprints free of charge) have the "correct" length for all likely needs, including this one.
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So when should chains on Rohloff geared bikes be replaced? So that sprockets are useable with a new chain without being flipped.
Andre says he changes his at 0.5%.
Others say 1%.
I am aiming to change my chains at 1% but that is simply based on what I have read.
Greater elongation must result in more sprocket wear.
I wonder what Chris’s chain elongation is at 22,000km?
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So when should chains on Rohloff geared bikes be replaced? So that sprockets are useable with a new chain without being flipped.
Andre says he changes his at 0.5%.
Others say 1%.
I am aiming to change my chains at 1% but that is simply based on what I have read.
You will probably get away with 1%, but if it skipped, then the sensible thing to do would be to put the old one back on.
I still don't understand why anyone would? You're throwing away chains with a lot of wear left in order to prolong the life of cheap components. You don't have the choice with a derailleur, simply because the sprockets wear at different rtes.
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"In theory" means I haven't tried it, among other reasons because the underlying assumption above is that all the components have roughly similar lifespans, which just isn't true
I've never heard anyone make that assumption. The theory is it's simpler and cheaper to change all three when the first component wears out than to keep changing one to preserve the other two. That first component will inevitably be the chain and by that time the other two will be worn too far to synch with a new chain.
In the scheme of things it's no big deal, you have a chain in a case and change it at 4,500km, others like the OP and myself, do five times the distance, save the cost of four chains, then have the cost of half a chainring and sprocket. No one is getting rich on the difference, I do prefer the simplicity of forgetting about it for years. If we were really concerned, we'd run wider chains, in a full chaincase, in an oil bath, and expect it to last the lifetime of the bike.
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So when should chains on Rohloff geared bikes be replaced? So that sprockets are useable with a new chain without being flipped.
Andre says he changes his at 0.5%.
Others say 1%.
The 0.5% is only a convenience, so that I change the chain at the same time as I change oil. It fits with the concept of my near-zero maintenance bike.
A better scheme if you want to get maximum miles for your money, for when you ride from home, not on tours halfway around the world, would be to have all the chains you expect to be consumed on one side of the sprocket/chainring to hand, and to fit them in order at some routine event (a distance, cleaning the chain, whatever), so that they can all wear in evenly with the gears. It has the advantage that you don't need to know with high precision how much wear per chain is optimal, you just spread it across all the chains and the metal will tell you when the limit is reached. Martin has written about this method, though not in these terms, and I think JohnR has mentioned it too.
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If we were really concerned, we'd run wider chains, in a full chaincase, in an oil bath, and expect it to last the lifetime of the bike.
Doing a version of that on my old utility bike. 1/8" TA chainring, 1/8" Sturmey-Archer sprocket and 1/8" KMC e101 chain, which is supposed to last for 10,000 kms or more (with the dedicated KMC chainring and sprocket that I don't have). Under a ChainGlider.
ChainGlider isn't quite a full chaincase, but it does protect against a lot of the muck picked up during all weather and/or off-road riding. In very wet conditions water gets in and will end up washing off the greasy coating provided by the manufacturer on the new chain. So there is still a bit of maintenance to be done, but much less than on an unprotected chain. Where I live, we had 35 consecutive rainy days in January and February 2026.
At the moment I just use an oily wet lube on the chain when the manufacturer's lube has gone, but I might try a chain grease advertised for motorbikes. I tried that in the past on an unprotected chain, but it picked up a lot of road dirt so it was worse than an oily wet lube, it might work better than an oily lube under a chaincase.
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A better scheme if you want to get maximum miles for your money, for when you ride from home, not on tours halfway around the world, would be to have all the chains you expect to be consumed on one side of the sprocket/chainring to hand, and to fit them in order at some routine event (a distance, cleaning the chain, whatever), so that they can all wear in evenly with the gears. It has the advantage that you don't need to know with high precision how much wear per chain is optimal, you just spread it across all the chains and the metal will tell you when the limit is reached. Martin has written about this method, though not in these terms, and I think JohnR has mentioned it too.
It was worth it for me with derailleur transmissions. The simplest way was with 2 chains, take the chain off when it needed cleaning, put the other one on, then clean and lube the one taken off ready to go back on the bike at the next change. Generally at 300 to 500 km intervals, but very weather dependent. The best I managed before having to replace the cassette was with 4 chains.
Still worth it on my Bromptons - the exposed transmission close to the ground picks up more muck than on a large wheel bike.
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A better scheme if you want to get maximum miles for your money, for when you ride from home, not on tours halfway around the world, would be to have all the chains you expect to be consumed on one side of the sprocket/chainring to hand, and to fit them in order at some routine event (a distance, cleaning the chain, whatever), so that they can all wear in evenly with the gears. It has the advantage that you don't need to know with high precision how much wear per chain is optimal, you just spread it across all the chains and the metal will tell you when the limit is reached. Martin has written about this method, though not in these terms, and I think JohnR has mentioned it too.
It was worth it for me with derailleur transmissions. The simplest way was with 2 chains, take the chain off when it needed cleaning, put the other one on, then clean and lube the one taken off ready to go back on the bike at the next change. Generally at 300 to 500 km intervals, but very weather dependent. The best I managed before having to replace the cassette was with 4 chains.
I am planning on doing similar with 2 chains:
- Chain A 0 - 5,000 miles
- Chain B 5,000 - 15,000 miles
- Chain A 15,000 - 20,000 miles or beyond………and back to Chain B again….
But at only 3,000 miles per year the 2 chains may outlast me - just reaching 9,000 miles now.
The chain that came off at 5,000 miles was grit free thanks to the chainglider so was not washed and is now stored in a bag ready for reuse.
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‘At the moment I just use an oily wet lube on the chain when the manufacturer's lube has gone, but I might try a chain grease advertised for motorbikes. I tried that in the past on an unprotected chain, but it picked up a lot of road dirt so it was worse than an oily wet lube, it might work better than an oily lube under a chaincase’
Motorbike chains are different to ours as they have O rings keeping the original lube inside the rollers - and dirt, water and chainlube out. Motorbike chain lube is more to lubricate the roller / sprocket interface.
Personally I think a thinner chain oil is better on a cycle chain so it can seep into the rollers (no O rings).
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Motorbike chains are different to ours as they have O rings keeping the original lube inside the rollers - and dirt, water and chainlube out. Motorbike chain lube is more to lubricate the roller / sprocket interface.
Personally I think a thinner chain oil is better on a cycle chain so it can seep into the rollers (no O rings).
I intend to try this product :
https://www.wemoto.fr/pieces/hu4897?srsltid=AfmBOoowINysP1_XKCMyTUz_1jrHSIgqqe9KwwuhWKu3zmcDzORBnRN9
It's pretty cheap, and the ads say it's easy to apply. If it doesn't work I'll go back to oil once the factory lubricant is gone.
I don't mind opening the ChainGlider to add oil after a period of wet weather on my own bikes, but there are two bikes with ChainGliders in the park of bicycles I maintain for a nature reserve on an island.
After slightly more than a month of rain (plus a bit of salt) the one with an oil lubricated chain had the oil washed off and the chain going rusty. The other one, with the original rather sticky factory lubricant on the chain, was perfectly OK.
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Motorbike chains are different to ours as they have O rings keeping the original lube inside the rollers - and dirt, water and chainlube out. Motorbike chain lube is more to lubricate the roller / sprocket interface.
Personally I think a thinner chain oil is better on a cycle chain so it can seep into the rollers (no O rings).
I had not thought to compare bicycle chains with motorcycle chains. My old Triumph motorcycles has a chain oiler, some of the engine oil (20W50 during most of the year) dripped on to it. Thus, I never oiled it. And half a century ago, there were no O rings in chains.
I suspect that as the chain that was wrapped around the counter tooth sprocket inside the gear case at highway speed, any dirt that was not hanging onto the chain really tight got flung off of the chain at speed. I stopped driving motorcycles a decade and a half ago.
I used to use a petroleum based lube on my bicycle chain, ranged from 20W50 to 90W140 gear lube, but it was a dust magnet. I switched to a wax based lube about a decade ago, very happy with that.
First attached photo shows my big chainring at the end of a tour with a lot of accumulated dust and dirt, that was shortly before I quit using a petroleum based lube. The chain was on the middle chainring, thus hard to see the chain in the photo, but it is very clear how dirty the chain must have been for the big chainring to be that dirty.
I mostly ride my derailleur bikes, but I do not use a Chainglider on my Rohloff bike either. I have no complaint with dripping on some wax based lube on a regular basis.
Second and third photo from a year ago, a very dusty day on a gravel trail with my Nomad Mk II. I rode 90 miles that day for exercise, the attached photos were middle of the ride. The chain is clean enough in my opinion, a lot cleaner since I switched to the wax based lube.
I do not try to keep track of how many miles I get on a chain. I regularly ride four or five bikes a year.
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Hi Martin,
I think that the motorbike chain lube you have quoted would be fine on a modern motorbike chain, which is what it is designed for, keeping the side plates rust free and the roller / sprocket interface lubed - but I don’t think it would get into the rollers of a cycle chain. The loads and speeds that a motorbike chain operates at are obviously a lot higher than on a cycle - hence it is important to keep the roller / sprocket interface clean and lubed to stop wear and heat build up. Motorbike chain lubes also keep the O rings ‘damp’ to help reduce friction when the links move as they go around the sprockets. It is surprising how hot an un-lubed motorbike chain can get!
I have one motorbike with a chain (I prefer shaft drive) which is a low powered 411 Royal Enfield Himalayan, used on and off road. The chain is the OE one with O rings but I have fitted a manual chain oiler to drip ATF fluid onto the chain to ‘wash’ dust off. I have tried using heavier gear oils but they do not clear the dust - ATF is very thin.
I have sprayed motorbike chain lube onto my cycle chain in the chainglider once. A spray lube is quite thin until it dries, and maybe some lube got into the rollers but most seemed to go onto the outside of the chain which is not really where I wanted the lube to go! So personally I now use a thin ‘wet’ cycle oil on my 2 bikes that have chaingliders and drip it onto the rollers.
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I have tried various motorcycle lubes at times in the past. Anything that worked reasonably well on a bicycle chain in wet weather also picked up a lot of dirt, so not good on an exposed chain. It might be different under a ChainGlider.
I think that the motorbike chain lube you have quoted would be fine on a modern motorbike chain, which is what it is designed for, keeping the side plates rust free and the roller / sprocket interface lubed - but I don’t think it would get into the rollers of a cycle chain.
The technical data sheet for MOTUL MC CARE C5 Chain Paste says "All types of chains: standard and with O-RING, X-RING, Z-RING.", so I'll give it a try.
I have one motorbike with a chain (I prefer shaft drive) which is a low powered 411 Royal Enfield Himalayan, used on and off road. The chain is the OE one with O rings but I have fitted a manual chain oiler to drip ATF fluid onto the chain to ‘wash’ dust off. I have tried using heavier gear oils but they do not clear the dust - ATF is very thin.
My brother has a Scottoiler system on his off-road motorbike. This drips oil (Scottoiler brand) onto the chain. Works for him, but not on a bicycle (I tried).
So personally I now use a thin ‘wet’ cycle oil on my 2 bikes that have chaingliders and drip it onto the rollers.
I do the same on my own bikes when the KMC factory lube has worn off. Quick and easy to do.
But dismantling/refitting the ChainGlider can be challenging for a user with no mechanical aptitude.
Under a ChainGlider the slightly sticky factory lube on KMC chains works for a long time, but after a lot of use in salty and/or wet conditions it eventually needs renewing with something. So I need something that lasts for a few weeks even under very wet conditions.
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I don’t remove any of the chainglider to oil the chain, I drip oil onto the top of the lower run of the chain just in front of the rear sprocket while pedaling slowly backwards.
The rear section comes off easily enough to remove the wheel and I removed the front part at 5000 miles in case the insides needed cleaning (there was a little grease). The next time I swop chains around I will try and pull the replacement through with the existing chain.
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You might consider measuring your chain later. The cheap small chain checkers are not very accurate, but you can measure the length of an entire chain when it hangs from a hook. One link is a half inch when new, thus 100 links is 50 inches from center of pin to center of pin. If it is 50.5 inches, that is one percent elongation. I think on a Rohloff bike replacing the chain when you are a bit over one percent elongation is a good time to replace it.
In case you were wondering. Assuming your method is correct ( which I am), and my maths and measurements are correct ( which I am less certain of) the chain is at ~1.8% elongation.
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Was the chain still operating OK with 1.8% elongation? No slipping or roughness?
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I thought it was still running fine. It was getting rather loose and the only issue had been the chain coming off, even that was only a couple of times in the last few months. It was not going to get better though and did tend to be at the most inconvenient moments…
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Thanks for the info Chris. If it could be tightened (eg by shortening it by one link or by half a link) then it would probably not fall off…….so I wonder how much elongation a chain can take and still be safely useable?
Sprocket wear would obviously also increase but I guess the sprockets could be successfully flipped and work with a new chain while the teeth still had flat ends.
Edited to add
Industrial chains appear to be designed to run to 3% elongation……so 1.8% is only just over half worn!
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Not my image, but it hasn't been posted in a while and it makes me smile, this is what a worn out sprocket look like ;D
(https://www.swedentoafrica.com/wp-content/uploads/IMG_0206_960x640.jpg)
https://www.swedentoafrica.com/drc-part-3-back-to-kinshasa/
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Re the bicycle lube and the method of applying it.
The method of running a bead of oil at side of the roller where it meets the side plate, on only one side, was brought into cycling by the late Sheldon Brown, presumably from motorcycle practice. I say presumably because I never saw Sheldon mention where he got it. On one side only because you want the oil to enter the roller on one side and flow through and out the other side, carrying the gunge out with it. Applying oil to both sides may/will form an airlock and the oil and gunge will whip itself into a grinding paste, precisely what you're trying to avoid.
As noted above about motorcycle chains by a couple of contributors here, I also saw the racing mechanic who looked after my big Laverda lay a bead of oil down the centre of the motorcycle chain; since he was ex-factory, I think we may safely conclude it was the correct procedure, approved by the designers of the bike.
Something else which I don't remember ever seeing mentioned here, is that Rohloff sells its own chain oil in a little 50ml squeeze bottle with pointy tip, ideal for applying a bead at the juncture of rollers and side plates. The actual oil is honey-colored but flows much more easily than cold honey, more like heated honey. Fifteen or so years ago, when I bought half a dozen or a dozen little bottles with my Utopia-Velo Kranich, it cost less than a fiver per bottle. Each little bottle would go a very long way. I'm still on my first bottle, having given some away, because there was no place for periodically-added lube in the zero maintenance bike I was developing. This oil replaced the wet wax I used previously, which irritated me by lasting only about a hundred miles per application, though it was a clean method, working by rolling up dirt in little balls of pale grey wax which would fall off inside the big ole Dutch chain cases I used before the Country and the Chainglider: the wax marbles were just shaken out of the bottom half of the chain case. The Rohloff chain oil is a persistent sticker; if you use it as sparingly as you're intended to, you'll never see a drop proving that gravity exists.
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I also saw the racing mechanic who looked after my big Laverda lay a bead of oil down the centre of the motorcycle chain; since he was ex-factory, I think we may safely conclude it was the correct procedure, approved by the designers of the bike.
The method I use on bicycle chains (when I oil them). Followed by wiping off any excess with a rag if I put a little too much on.
Something else which I don't remember ever seeing mentioned here, is that Rohloff sells its own chain oil in a little 50ml squeeze bottle with pointy tip, ideal for applying a bead at the juncture of rollers and side plates.
The Rohloff chain oil is a persistent sticker; if you use it as sparingly as you're intended to, you'll never see a drop proving that gravity exists.
Rohloff also sell (sold ?) their chain oil in 1 litre bottles. As I maintain a lot of bicycles I bought a litre a decade or so ago, it will probably last me for the rest of my life. The Rohloff chain oil is a bit sticky, but still gets washed off eventually in very wet conditions. And picks up dirt like any other wet lube when used outside a Chainglider.
I have a litre bottle of a lighter oil, called Morgan Blue Summer oil when I bought it, which works well in clean, dry conditions as it is less sticky. Don't use it much now, I used to put it on derailleur bikes that I only rode in good weather, the only derailleur bike I have now is one of my Bromptons and that is used in all weathers.
This oil replaced the wet wax I used previously, which irritated me by lasting only about a hundred miles per application, though it was a clean method, working by rolling up dirt in little balls of pale grey wax which would fall off
I tried two methods using wax, the one where you melt the wax and put the chain in the melted wax and then hang it up to dry, also the easier way with a water-based wax emulsion applied to the chain on the bike. Cleaner than anything else, but no good if used in a rainy climate as it doesn't protect the chain for very long.
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In my opinion, the best chain lubricant under a ChainGlider is the factory lube that comes on KMC chains when they are new, at least the ones designed for hub gears/single speeds. This lasts for a very long time inside a ChainGlider. But it does eventually wear off/wash off in very wet or very dirty conditions. On an exposed chain, it picks up dust if used off road in dry conditions and, like anything else, it picks up muck if used in wet conditions.
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You might consider measuring your chain later. The cheap small chain checkers are not very accurate, but you can measure the length of an entire chain when it hangs from a hook. One link is a half inch when new, thus 100 links is 50 inches from center of pin to center of pin. If it is 50.5 inches, that is one percent elongation. I think on a Rohloff bike replacing the chain when you are a bit over one percent elongation is a good time to replace it.
In case you were wondering. Assuming your method is correct ( which I am), and my maths and measurements are correct ( which I am less certain of) the chain is at ~1.8% elongation.
For 22,000 km on that chain, I am not surprised at 1.8 percent elongation. I mentioned before that your sprocket looked very good for that kind of distance, and now I am even more impressed by the lack of wear on the sprocket.
Chain elongation occurs on the links with outer plates, not on the links with inner plates. In your case that does not matter because your sprocket has an odd number of teeth. I believe that Thorn always installs sprockets with an odd number of teeth on their bikes.
Rohloffs when new come with sprockets with an even number of teeth. I assume they still come with 16, but I would not be surprised if they have changed. I bought my Rohoff hub from a seller other than SJS, mine came with 16 teeth.
I am not saying one method is better than the other, just that they are different. I do not believe that Thorn has ever explained why they do it the way they do, but I suspect it is because then all teeth wear the same way. And then when you put a chain on the sprocket after a repair, it does not matter which links go on which teeth. But since I have an even number, I need to be careful about that.
I have shown these photos a few times on this forum, attached. I took these photos six years ago just before I flipped my sprocket, which is why my sprocket is so clean. Note that one of the sprockets has a small notch cut in it, I am always careful to make sure when I put a chain on the sprocket that an outer plate link goes on the notched sprocket. I also added some yellow paint to make that tooth easier to find when dirty.
A chain and sprocket wear together when you have an even number of links. And since only the links with outer plates elongate, that is why every other tooth on my sprocket is more worn, that is to match how the chain and sprocket wore together. I have replaced the chain several times since I built up that bike, but I never replaced or flipped the sprocket. Thus my sprocket represents several worn out chains.
It is very hard to look at a sprocket and make a good estimate on how much metal is no longer there, but if you look at just the third attached photo, when you consider that each tooth used to be exactly above the round hole below it, if you only look at one tooth with the underlying hole, you can see that the tooth is slightly offset to the right of the hole, that is because some of the metal on the left side of the tooth is now gone. The tooth on the left is even more offset from the hole below it than the tooth on the right, that is because a lot more metal has been worn off of the tooth on the left.
With that in mind, I reiterate that your sprocket looks extremely good for that much chain wear, your sprocket for reference is at this link:
https://thorncyclesforum.co.uk/index.php?action=dlattach;topic=15698.0;attach=21713;image
I have no idea why your sprocket looks that good, it should not.
Off topic - my chainline is not perfect, that is by choice, I wanted my Q factor (width between pedals) narrower on my Rohloff bike to match my derailleur bikes. The first and second attached photos show different sides of the sprocket, one side has more wear on the sides of the teeth that had inner plate links than the other photo because of this slight off-line chainline.
I do not keep track of how many miles I get on each chain. I frequently ride four or five different bikes. Only my Nomad Mk II is a Rohloff bike, the other bikes are all derailleur bikes. And there are many years when my Rohloff bike gets less than 500 miles on it. I replace the chains on my derailleur bikes when they are at 0.75 percent elongation. Thus, I go through a lot of chains on my derailleur bikes.
I hate to throw out chains with only 0.75 percent wear when I often push my Rohloff chains to over a full percent. So, starting a few years ago, I now put my 0.75 percent worn chains onto my Rohloff bike to get some more wear out of each of those chains before I discard them. I probably am the only one that does this, but I am sure it is quite rare for most Rohloff bike owners to also have a supply of chains worn out on derailleur bikes to only 0.75 percent elongation.
That said, I am now planning a bike tour for my Nomad this year that is roughly a thousand miles. I have been wondering if I should put a 0.75 percent worn chain on it to start my tour, or a brand new chain with no wear. But I have a few weeks to make that decision.
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This discussion from 14 years ago still has relevance...
https://thorncyclesforum.co.uk/index.php?topic=4655.0#msg22907
Best, Dan.
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Not sure if PH’s image of a worn sprocket is Ian Wallis’s or not, but I have seen images of the worn sprocket he left pinned on a wall in an Australian bar and it looked very similar! If I Remember Right he rode from UK Southwards and the original chain and sprockets were only replaced very late on his journey.
Perhaps we all change parts much too soon??? A 1:1 chain system has a lot more tolerance than derailleurs.
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This discussion from 14 years ago still has relevance...
https://thorncyclesforum.co.uk/index.php?topic=4655.0#msg22907
Best, Dan.
I had not read that before, but then I bought my Rohloff in 2013, so might have read the first sentence and moved on.
Thanks for remembering that.
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Perhaps we all change parts much too soon??? A 1:1 chain system has a lot more tolerance than derailleurs.
I think it depends a lot on the derailleur system you are using.
My eight speed bikes use a Sram 850 cassette, cost is about 30 USD before state sales tax, in my state that would be about 32 USD. I think Dan does not have a sales tax. That is not a significant cost. And a KMC eight speed chain, a Z series about 15 USD and an X series about, Amazon has that for about $15 USD too. Thus, very low cost to replace. Replacing both and you are paying less than $50.
That said, I think you replace those parts sooner on a derailleur system than on a Rohloff or other IGH system, so the derailleur costs likely are a bit higher with added frequency. And an eight speed cassette likely costs about a third more than a Rohloff sprocket.
My road bike is a 10 speed with a Campy cassette. Chain is about 20 USD but the Miche 12-29 cassette that I am using on it is pushing about 70 USD, so replacing both is a bit under 100. Thus roughly double the cost of an eight speed system. Note here, I priced a 10 speed cassette for a Campy drivetrain, which is what I have. I am clueless how that compares to Shimano or Sram 10 speed cassettes.
Of the two options above (eight or ten speed), I find that on an eight speed system, I wear out the 16T and 18T sprockets first, the 21 soon after. So, I am replacing the cassette when only three sprockets are worn out. But I think on a 10 speed system, that I spread most of the wear over more sprockets, so that cassette might last a bit longer than on an eight speed cassette if I spread most of the wear over the middle four or five sprockets.
Since the latest fad is 11 or 12 speed 1X systems, that is where the costs can really go up. The recommendation to replace a chain drops to 0.5 percent instead of 0.75 percent on an 11 or 12 speed system. And the cassettes are often a three digit cost in USD.
I suspect that on a 1X11 or 1X12, that you might be replacing that cassette when you have only worn out two or three of the sprockets. If that 11 or 12 speed system was a 2X system, then I think you would spread the wear over more sprockets on the cassette than with a 1X system.
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What I meant, George, was that after seeing how badly worn the sprocket was that PH posted (which was obviously in use) that perhaps we all change them too soon.
A 1:1 final drive is much more tolerant of wear than a derailleur system……where almost invisible sprocket wear can give problems as different sprockets will have different amounts of wear so some will not mesh with the chain.
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What I meant, George, was that after seeing how badly worn the sprocket was that PH posted (which was obviously in use) that perhaps we all change them too soon.
A 1:1 final drive is much more tolerant of wear than a derailleur system……where almost invisible sprocket wear can give problems as different sprockets will have different amounts of wear so some will not mesh with the chain.
Agree. As noted above, I have started to put worn out chains from my derailleur bikes onto my Rohloff bike, depriving my Rohloff bike of having newer chains.
That exceptionally worn out sprocket that PH showed the photo of had 16 teeth, an even number of teeth, you can see that several teeth were broken off but in that case those broken teeth were every other tooth. I mentioned above that Rohloff hubs are usually fitted with a 16 tooth sprocket when new if you did not buy it on a bike from Thorn.
I also think that Thorn bikes that use a eccentric bottom bracket may be more tolerant of wear than ones that use a spring loaded chain tensioner. With a very worn chain on a very worn sprocket, as you pedal, each chain link will climb up each tooth as the wheel rotates, causing more tooth wear. The limiting factor on how high a chain can climb up a tooth with a spring loaded chain tensioner is the spring, thus if you pedal harder the chain could skip over the teeth. (Like happened last summer on one of my derailleur bikes, the chain was not yet at 0.75 percent elongation but some sprockets on the cassette were sufficiently worn that the chain skipped when pedaling hard.) But with the Thorn eccentric, as long as your chain is not too loose, it won't skip because there is only a limited amount of extra slack in the part of the chain that is normally loose as you pedal.
I might have mentioned above that I am going on a tour in the near future, not sure which chain to put on my Nomad Mk II for that trip. I anticipate a bit over a thousand miles on that trip. And I expect it to have more wear than normal as the bike will be carrying a heavier load, expect it to be exposed to wet weather more often, and probably will get less lube than typical. But I do not want to put a chain on that has so much wear that I could be asking for trouble. The chain currently on the bike has the eccentric near the maximum for amount of chain tightening that can be applied.
I found one chain in my collection of used chains that has a bit over 0.5 percent wear from a derailleur bike, I think that is the one that I will put on for my trip. It should still have plenty of life left on it, so it should not be troublesome on my trip. Maybe I should swap chains today, and measure my old one for percent elongation before I discard it?
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I have gone to 38 / 17 on both my bikes with the 38 being N/W so that the chain is always in phase…..
If you do need a new chain then you can always buy one in Scotland - but an extra 1000 miles on a 0.5% elongated chain does not sound excessive….or fit a chainglider and any wet weather will not be an issue and little lube will be needed!
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One thing that doesn't seem to be have discussed :
- What effect does using a worn chain sprocket, chainring have on the transmission efficiency ? To me, a new chain and sprocket "feels" more efficient than a worn transmission, but some of that is probably psychological.
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One thing that doesn't seem to be have discussed :
- What effect does using a worn chain sprocket, chainring have on the transmission efficiency ? To me, a new chain and sprocket "feels" more efficient than a worn transmission, but some of that is probably psychological.
If you ask a hundred bicyclists what the best chain lube is, you will get 150 different answers. Neglecting different efficiencies from different chain lubes, ... ... ...
As I noted in my lengthy post yesterday, a worn chain will have the links rubbing on more of each individual tooth. How much of a fraction of a watt is that for each link? Not much. Could it be measured? Probably could.
When they can measure how much additional wattage is consumed from a derailleur drivetrain that does not have a perfect chainline, I am sure they could find some additional friction in a worn drivetrain. And larger chainrings and sprockets have less friction from less friction at the pin and link as the part of the chain that is under tension unwraps from the sprocket and then wraps around the chainring, that can be measured too.
With the proponents on this forum for chain gliders, that is additional friction.
Bottom line, I often leave my dyno powered lights on in daytime, even when I am on a bike trail where there are no cars to worry about because I can't feel the extra lost wattage from that, so I don't worry about it. That is several extra watts lost, probably a bigger loss than the extra friction at the worn drive train.
Yesterday I swapped chains on my Nomad Mk II, I leave for a bike tour in a bit under three weeks. I use a smaller chainring for lower gearing for bike tours, I changed from a 44 to 36T chainring yesterday in the process of changing chains. The chain I put on for my tour is at 0.5 elongation from wear on a derailleur bike, but less than 0.75 percent elongation. The chain I removed will be discarded, it measured at 1.0 percent elongation (25 inches of chain measured at 25.25 inches.) I would rather suffer a bit of extra friction instead of incurring the cost of a new chain as I prep for my tour, even though a new chain would only set me back a bit over $15 (USD) on Amazon.
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One thing that doesn't seem to be have discussed :
- What effect does using a worn chain sprocket, chainring have on the transmission efficiency ? To me, a new chain and sprocket "feels" more efficient than a worn transmission, but some of that is probably psychological.
A smart move when one suspects that the desired data point would be too small to measure accurately, is to find either an analogue, or some way to alter the relationship by a few factors, often by applying the cause to the full length of the whole rather than some fraction of it, so that you measure a size easily picked up by available instruments and your answer is simply the result of a division.
A bit of lateral thinking gives us a full length to work with: When the chain has broken off enough teeth on a very worn sprocket so that the chain can no longer engage the sprocket to pull it around, the transmission has been 100 percent degraded to zero percent efficiency.
If we take that obvious condition of the transmission with another obvious but related condition, say when the bike was brand new, unridden, we can calculate the extra mileage that a component gives us, say a different chain, or a Chainglider. That can then be taken as an unrealized efficiency. For instance, the Chainglider multiplied the chain life on my bikes between three and four times. Let's work with a factor of three. That's a clear gain of 200 percent. QED: it becomes easy to understand why I'm so enthusiastic about the Chainglider.
Because I threw off what has now become clear are considered halfworn chains by some on this forum, that already deeply impressive efficiency gain is only half the potential gain at 1 percent chain elongation. So now we're up to 400 percent potential gain.
I suspect that's still not all the potential, because the sprockets in the photos in this thread were very likely taken when chains had been abused well beyond 1 percent elongation. But we don't have any further data.
Neglecting different efficiencies from different chain lubes, ... ... ...
[GEORGE, HAVING QUOTED MARTIN, OFFERS AN IMPRESSIVE ANALYSIS OF HOW VARIOUS FORMS OF TRANSMISSION WEAR, EACH SMALL ENOUGH TO REQUIRE SPECIALIST EQUIPMENT AND METHODS TO MEASURE, MAY OR MAY NOT ADD UP TO SOMETHING SIGNIFICANT.]
With the proponents on this forum for chain gliders, that is additional friction.
There's bound to be a minimum level of friction in any transmission system where metal rubs on metal, or hydraulic fluids move masses or resist their movements.
I'm not so much fascinated by that practically irreducible friction which is the unavoidable overhead of any chain or belt drive system. One of the benefits of the Chainglider is that it permits us to eliminate a lot of guesswork because the Chainglider by the very nature of its effective enclosure sums together such fraction of each of these fractions of a percent as can reasonably or even unreasonably, right out at the furthest frontier of rationality, be expected to be eliminated. This I'm willing to take as the point where a further reduction of one percent of an, already fractional, amount of friction will cost not ten percent but hundred percent more effort, time and money, in short where we enter the region of irrational obsession and absurdity.
In the common game of comparing derailleur efficiencies with those of hub gearboxes, there's a bedeviling factor: The derailleur transmission in a real life comparison on the roads is not statically efficient: it declines dynamically from perfectly clean and tuned at the outset of the test as the chain and gears pick up dirt. An open Gates type belt drive ditto, to a presumed lesser extent than the derailleur. A fixie or hub gear chain under a Chainglider would come closer to a steady state efficiency, altered only, as you imply in your post above, in a minimal way, from the qualities of the lube used on the chain. I don't think a meaningful measurement of the difference can be taken under a thousand miles, and in real life I wouldn't sanction any expenditure on measuring something we can do nothing further about.
Bottom line, I often leave my dyno powered lights on in daytime, even when I am on a bike trail where there are no cars to worry about because I can't feel the extra lost wattage from that, so I don't worry about it. That is several extra watts lost, probably a bigger loss than the extra friction at the worn drive train.
I do the same (because before I gave up the car altogether, we had a Volvo Estate to run the child safely to school, and I was impressed by its daylight running lights), but I'm not at all certain that the loss is 'several' watts. Modern hub dynamos are really very efficient and low friction, say compared to a generation earlier, where it was repeatedly found that one Shimano hub dynamo consumed less power when it was switched on than when it was switched off! Also, even modern hub dynos are design iterations from their ancestors, and are not yet fully acclimatized to the now-standard LED lamps which fully replaced filament bulbs less than twenty years ago. As a consequence, bicycle hub dynos have power to spare: It wouldn't surprise me to hear they're the most efficient active component, including the human, on every bike fitted with a modern hub generator. I wouldn't expect you to notice anything from the hub dynamo, except that it makes light and charges the phone on demand.
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In the common game of comparing derailleur efficiencies with those of hub gearboxes, there's a bedeviling factor: The derailleur transmission in a real life comparison on the roads is not statically efficient: it declines dynamically from perfectly clean and tuned at the outset of the test as the chain and gears pick up dirt.
Agreed. Added to that, derailleur drivetrains operate with various degrees of chain deflection and sprocket/cog diameter vary between gears as one shifts across the cassette. I am still deeply suspicous of the performance losses associated with "one-bye" (single chainring) drivetrains in all but the middle cogs of the cassette. The variations between smallest and largest cogs on the cassette occur at the most extreme chainline angles and the difference in cog diameters is also extreme (i.e. 10t vs 40t+). Perhaps sheer convenience in shifting and relatively greater simplicity accounts for their popularity. I'm not yet sold, preferring to run my derailleur triples (three chainrings, front mech) and shift to keep my chainlines as straight as possible to minimize friction while maximizing component life. In summary, if you shift a derailleur drivetrain frequently and run at the extremens, the lateral chain wear is bound to be accelerated compared to a drivetrain where the chain runs straight.
I value my Fixie and Rohloff-hubbed Nomad for their constant straight chainlines among their other virtues.
Best, Dan.
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In the common game of comparing derailleur efficiencies with those of hub gearboxes, there's a bedeviling factor: The derailleur transmission in a real life comparison on the roads is not statically efficient: it declines dynamically from perfectly clean and tuned at the outset of the test as the chain and gears pick up dirt.
That also happens with an uncovered hub gear transmission. But more slowly, as the derailleur hangs lower and closer to the ground. And with only one chainring and sprocket the hub gear system is easier to clean than a derailleur system.
Brakes also make a difference on an uncovered transmission, a drum, roller or disk brake doesn't spray water and muck around like calliper brake does. Worse brake I had in this respect was a U-brake, placed under the chain stays, ideally placed to put the maximum amount of water and muck onto the chain.
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If you ask a hundred bicyclists what the best chain lube is, you will get 150 different answers. Neglecting different efficiencies from different chain lubes, ... ... ...
I have seen tests that indicate that some sort of wax is the most efficient chain lube. But wax doesn't work well for my riding conditions. These tests also showed that a derailleur transmission was slightly more efficient after a certain amount of use, rather than when it was brand new. After that point the efficiency declined with wear.
Also seen tests that showed that a well lubricated but worn chain was better than a new chain without lubrication.
With the proponents on this forum for chain gliders, that is additional friction.
When I first started using a Chainglider I did some timed rides round the same circuit before and after fitting it. I decided the difference wasn't significant.
Bottom line, I often leave my dyno powered lights on in daytime, even when I am on a bike trail where there are no cars to worry about because I can't feel the extra lost wattage from that, so I don't worry about it. That is several extra watts lost, probably a bigger loss than the extra friction at the worn drive train.
I generally leave my hub dynamo lighting permanently on. With modern LED lamps I reckon it helps drivers to see me, same reasoning as motorcyclists. When I had bottle dynamos I hardly ever used the lighting in daytime.
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... I am still deeply suspicous of the performance losses associated with "one-bye" (single chainring) drivetrains in all but the middle cogs of the cassette. The variations between smallest and largest cogs on the cassette occur at the most extreme chainline angles and the difference in cog diameters is also extreme (i.e. 10t vs 40t+). Perhaps sheer convenience in shifting and relatively greater simplicity accounts for their popularity. I'm not yet sold, preferring to run my derailleur triples (three chainrings, front mech) and shift to keep my chainlines as straight as possible to minimize friction while maximizing component life. ...
Fully agree.
My derailleur bikes all have triples, except my road bike is a double because I bought that as a complete bike, not one I built up from parts.
My two derailleur touring bikes, the Thorn Sherpa (26 inch wheels) and Lynskey Backroad (700c wheels), both have 3X8 half step plus granny drive trains. When I avoid the two most cross chained gears for each chainring, I still have 18 effective gears with a total range of 558 percent. I went with this gearing for touring, as it gives me a few widely spaced gears for hill climbing on my granny chainring and closer spaced gears for where I spend most of my time on flatter ground.
https://gear-calculator.com/?GR=DERS&KB=24,42,46&RZ=11,12,14,16,18,21,26,32&UF=2204&TF=72&SL=2.2&UN=MPH&DV=teeth
The technology is 30 years old, but it beats the 1X drivetrains in performance, plus the cost of expendable parts is much less.
That said, I understand the preference for a 1X system for a single shifter with sequential shifting, anyone that rides a bike with a Rohloff certainly can appreciate that.