Author Topic: Chaincased Rohloff drivetrain -- first report  (Read 4419 times)

Andre Jute

  • Hero Member
  • *****
  • Posts: 4070
Chaincased Rohloff drivetrain -- first report
« on: April 07, 2010, 10:35:34 am »
Hobbes,
Please post what condition you find your transmission in when you take the chain case off.
We are all eager to hear, because an effective chain case which fits over a Rohloff set up has been a 'holy grail' which is still unresolved.

Julian.

Julian, I give a full description because someone else may find it useful, but you high-mileage guys are going to be disappointed because at my low mileage there isn't much to learn yet.

***

I've elsewhere on the board described various types of  chaincases and experience with them -- see http://www.thorncycles.co.uk/forums/index.php?topic=2233.0

My Utopia Kranich -- see http://www.audio-talk.co.uk/fiultra/Andre%20Jute's%20Utopia%20Kranich.pdf -- has now covered 2570km in 15 months and the first annual warranty inspection is overdue. The Utopia chaincase (described in "A Fully Enclosed Chaincase That Works", URL above) is complicated to remove completely, so I'm not keen to dismantle it unless absolutely necessary. The inspection and oiling port allows one to inspect part of the sprocket and a link or two of the chain, more by turning the pedals backwards.

The KMC X8 99 is an all-silver chain constructed for long life under heavy load, in short a touring chain. It has received a few drops of Oil of Rohloff at the same 500km intervals as the external klickbox was greased. (Apparently many Rohloff owners do not know that the external klickbox should be greased -- see p7 of the manual.) A few drops of Oil of Rohloff on the chain means a very few; that stuff goes a long way! More than a few will drop off and find its way through the joints in the Country chaincase, which is split at the top and the bottom, and drip out.

In this regard, my cheaper Dutch style fully enclosed chaincases are superior to the Country, as they are split at the sides at about the level of the chainstay and the hollow bottom catches oil excess. The Country isn't exactly dirty, but just to be certain I'd give it a quick wipe before I rode it in my cricket whites, which is unnecessary with the Dutch style chaincases; for my normal wear of cords or khakis the Country is more than clean enough if you don't overdo the oiling of the chain.

Utopia makes the Country chaincase very light indeed. The downside of light weight is that a couple of small pieces have broken off the inspection port cover where it overlaps the main part of the sprocket cover, but not enough to impair its function. More disturbing is that I didn't get a reply to a letter listing replacement parts I want to buy and asking how I should pay for them. The Country is an entirely proprietary chaincase, with no second source... I imagine that one might get three to five low-mileage years out of it by bodging up parts and liberal substitution of duct tape for rubber bellows but that isn't good enough for a 150 euro chaincase.

If my Country does give up the ghost and there is difficulty with repair and replacement parts, I have worked out how to make up a Hebie Chainglider to fit a) any Rohloff-approved chainwheel with b) 15, 16 or 17 tooth Rohloff sprockets at c) any wheelbase length, all from Chainglider spare parts which since I wrote the earlier article have become more freely available, at least in Germany while, significantly, some of the new stockholders do mailorder. It might be bothersome and expensive in postage if separate parts have to be bought from different dealers, but it appears to be doable.

***

For the major annual service, I made a standard inspection through the port with a spare sprocket in one hand for comparison; the sprocket on the bike does not seem worn at all, and the oil on it is good and runny and does not feel gritty between thumb and forefinger. What little muck there is seems to have migrated to the sides of the chain. On earlier 500km miniservices  I wiped the outside of the chain by holding a piece of kitchen tissue in the inspection port and turning the pedals backwards. This time I left it, and didn't add any oil either, as there seems to be plenty of oil on all moving parts.

In short, for the major annual service of the chain and sprocket, I did nothing because nothing seems on inspection to be what is required.

The external klickbox internals were serviced as at every 500km miniservice with Fineline Ceramic Grease. I'm not impressed with the way this grease disappears even in my entirely undemanding use (no salt or mud and the bike is hardly ever wet). I think I might just go to standard Teflon grease, sticking to the Fineline brand.

***
It is not possible in the Utopia Country chaincase to measure chain elongation without disassembly. Nor is it possible to see the teeth of the chainwheel without disassembly.

But this matters less than you might think. The chain runs straight in singlespeed mode because all the gearchanges happen inside the box, and on a proper touring Rohloff installation there shouldn't be a crude spring-loaded chain tensioner but instead either sliding frame ends or an eccentric bottom bracket. In such a chaincase setup one would accommodate drivetrain wear by simply moving the sprocket and chainwheel centres further apart; all parts would wear together; sprocket, chain and chainwheel will be replaced together or, more precisely, when the chain starts skipping the chain will be replaced and the sprocket and chainwheel flipped over to use the second side.

The KMC X8 99 chain on the link I wiped for inspection seemed new. On a Rohloff installation such as I describe above, it is normal to run the chain slack, with a minimum of five millimetres of movement top and bottom, better slacker still. For a chain it's a pretty low stress environment. My crankset is steel, from Amar in India (bought for the aesthetics of its thin steel arm), so it might last as long as the chain and one side of the sprocket. Even if the not overly expensive chainwheel despite being steel sets the limit of service of the drive set, I can clearly see that this drivetrain will give several multiples of the disappointing service life I got from Shimano chainwheels and sprocket and SRAM chains on my other hub gear/chaincase bikes. But it is impossible to eyeball the sprocket and chain and say, "They will last x times as long as the present mileage." Chain and sprocket both look so close to new, I'm starting to have hopes of making at least the lower end of the extraordinary mileages on drive sets reported here by several posters.

Hobbes

julk

  • Hero Member
  • *****
  • Posts: 974
Re: Chaincased Rohloff drivetrain -- first report
« Reply #1 on: April 07, 2010, 06:13:06 pm »
Hobbes,
Many thanks for the extended report.

It sounds like the chaincase is doing the job required, slightly worrying that the investment you have made is not being supported by the supplier at this point in time.

I am sure your post will be read with interest by many more than me.
Thanks again.
Julian.

vik

  • Full Member
  • ***
  • Posts: 246
Re: Chaincased Rohloff drivetrain -- first report
« Reply #2 on: April 08, 2010, 02:26:48 am »
Thanks for the report.  I hope Thorn is listening and since they've gone to so much trouble to optimize their touring bikes for the Rohloff maybe they will take the last step and design/build/sell a purpose built chaincase... ??? :o ;D
Safe riding,

Vik
www.thelazyrando.com

Andre Jute

  • Hero Member
  • *****
  • Posts: 4070
Re: Chaincased Rohloff drivetrain -- first report
« Reply #3 on: April 22, 2010, 01:15:18 pm »
Thanks for the report.  I hope Thorn is listening and since they've gone to so much trouble to optimize their touring bikes for the Rohloff maybe they will take the last step and design/build/sell a purpose built chaincase... ??? :o ;D

Having read here of commuters getting many multiples of the chain mileages I achieved on chaincased Shimano hub geared bikes, I'm not persuaded that a chaincase will double your already extensive chain life, or whatever you're hoping for. The fellows who're getting these big mileages on chains must already be doing everything right!

A cheap plastic Dutch-style enclosed chaincase will not last long on a touring bike used on rough roads; it'll shake itself apart. That leaves the Hebie Chainglider and Utopia Country. They might last longer. Might. The Country, of which I have experience, is lightweight and rebuildable but seems pretty resilient; the Chainglider, being simpler, might last a few years before it got damaged or worn out.

But look at the cost in relation to the extra drivetrain life. If the chaincase adds five per cent (Hebie Chainglider) or even ten per cent (Utopia Country) to the price of your bike, it could be more years than the thing will last before its cost is recovered in longer chain life. The difference has to be made up in convenience and cleanliness, or the simple absence of the nuisance of having to use trouser clips on your office pants. This matters to me who rides in cords or khakis such as I normally wear to sit at my desk, so that the cost of a chaincase is considered part of the bike-- when I looked at the Raven, still on my shortlist, I automatically added the cost of a Hebie Chainglider. But I think most other cyclists in the Rohloff-equipped Thorn market have already made their accommodations vis a vis clothing and changing facilities.

I'm therefore not surprised that Thorn, who must satisfy a very wide range of cycling modes, haven't yet chosen a chaincase as the "official" Thorn fitment, and you can just about forget them going it alone by designing their own because it will, considering the number of units they can hope to sell, be even more expensive than Utopia's Country.

Also, I'm at a loss to conceive of anything Thorn could come up with that would be superior in conception to the Chainglider or the Country, and if either conception is better made (difficult to do in small numbers unless the thing is very much heavier than either of those two) the already high price will skyrocket. As Colin Chapman said, "Quality, low price, low weight -- choose any two."

In fact, I think it far more likely, as was discussed a few months ago, that elite low volume bike makers like Thorn will in five years all be making belt drive bikes, and discussion of chaincases will seem an anachronism. Belt drive is a mature technology the price of which will fall drastically the moment a few mainstream producers pick it up. In a decade or two, the chain will be reserved for UCI races...

Andre Jute
Visit Jute on Bicycles at
 http://www.audio-talk.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html

Andre Jute

  • Hero Member
  • *****
  • Posts: 4070
Re: Chaincased Rohloff drivetrain -- first report
« Reply #4 on: May 27, 2010, 01:27:21 am »
J

If my Country does give up the ghost and there is difficulty with repair and replacement parts, I have worked out how to make up a Hebie Chainglider to fit

Hobbes

I'm afraid the Utopia Country has clocked out, as described in   http://www.thorncycles.co.uk/forums/index.php?topic=2233.0

Hobbes