Thorn Cycles Forum
Community => Rohloff Internal Hub Gears => Topic started by: frog on January 13, 2007, 12:36:55 PM
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Riding home on Thursday on my Raven Tour and even above the howling wind I could hear this click from around the cranks. Every revolution just as the cranks went vertical.
I've tightened the bolts which hold the cassette in place (adjusted 2 weeks ago), bolts which hold the chain ring on, pedals, and crank bolts. The chain is well libricated and the chain guage says it's still in life. Libricated the pedals as well,
Anything else I should be looking at as well please?
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quote:
Originally posted by frog
Riding home on Thursday on my Raven Tour and even above the howling wind I could hear this click from around the cranks. Every revolution just as the cranks went vertical.
I've tightened the bolts which hold the cassette in place (adjusted 2 weeks ago), bolts which hold the chain ring on, pedals, and crank bolts. The chain is well libricated and the chain guage says it's still in life. Libricated the pedals as well,
Anything else I should be looking at as well please?
When you say cassette, do you mean eccentric? I had a similar problem a few months ago and it was the eccentric that needed tightening.
Kevin
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That's right the two bolts under the bottom bracket. Sorry for the misdirection [:)]
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You’re not the only one, have a look here;
http://www.sjscycles.com/forum/topic.asp?TOPIC_ID=790&SearchTerms=chain,,
For more information on possibilities, have a look at this Sheldon Brown article;
http://www.sheldonbrown.com/creaks.html
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quote:
You’re not the only one, have a look here;
http://www.sjscycles.com/forum/topic.asp?TOPIC_ID=790&SearchTerms=chain,,
For more information on possibilities, have a look at this Sheldon Brown article;
http://www.sheldonbrown.com/creaks.html
Flippin' 'eck! What a nightmare! At least the derailleur stuff isn't applicable. I've got a gentle 20 mile ride planned for tomorrow morning. I'd better take some ear plugs to stop myself getting paranoid.
Thanks for the replies folks!!
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I had a similar thing after I refitted chain. I refitted it again and the click disappeared. I suspect it was seated 1 tooth differently (I read somewhere, that link/tooth can wear togetether on a single sprocket setup, putting the chain back can fit non-matched links to non-matched teeth so you need to move the chain along by 1 tooth).
This could be total and utter nonesense but re-fitting the chain fixed mine.
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Went for the ride this morning. Not much wind so I could hear almost everything without trying. First few miles went fine but at the first hill, when I had to put some pressure on the drive train, back it came. Bugger.
Was more than a bit concerned with removing the chain because this meant undoing the bottom bracket adjusting bolts and I didn't want to be in the postion where I'm trying to tighten up the bolts into holes whose side would collapse because they were too close to their adjacent ones.
Was a bit confused by trying to get it set in my mind which way the chain had come off it's circuit so I could be sure I actually turnbed it around rather than just putting it back on the same way it came off. In the end I broke the chain at the top of its run, Unwrapped it from the cogs and then changed left hand with right hand.
I'm used to all the malarky which goes with chain tensioners on rear mechs and remembering to feed the chain through the front changer so this was much easier than I expected. Coupling the links back together was pretty easy too.
It was about now I started to kick myself. I'd made no note of where the EBB was mounted in relation to it's side to side motion. I decided that centrally with equal amounts of EBB recessed into the shell would have to do for the time being. There's about 1mm recess on each side.
I used a 15mm ring/OJ spanner to tighten up the EBB adjusting bolts. It's about 8 inches long so I just used fingers at the end of the spanner to finally tighten them up. I was more afraid of stripping the thread on the shell or bolts rather than damaging the BB casing. The latter can be replaced much easier than the former.
Now for a flash of inspiration. I know someone's thought of this before but it deserves repeating. You can make small adjustments in chain tension without the risk, well reduced risk, without making elongated holes in the BB. The EBB only adjusts for half a revolution. So, If I want to adjust my chain the first time I adjust it clockwise. The second time I adjust it anti-clockwise. This way the holes are miles away from the first set. On the third adjustment I rotate it back clockwise again. The holes I'll make in the BB are the correct distance from the first set and I've had my chain correctly tensioned for the whole time.
There is probably no good engineering reason for doing it other than a taunt chain loks a lot better than a slack one.
So, job done and I'll find out just how I was at it at 06:10 tomorrow morning [:)]
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Frog,
If I understand your clockwise and anticlockwise method, one way you will be rotating the bottom bracket cups to the physically lowest position. Thorn warn that this can lead to the fastening bolts penetrating the thin part of the eccentric and damaging the bottom bracket cups....
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Interesting! Does this mean the spikes on the end of the bolts penetrate the eccentric carrier or the bottom bracket?
Just to clarify. This means that all adjustment of the EBB should be done by rotating the unit FORWARD (in the direction of bike travel) so the meatier part of the EBB is presented towards the retaining bolts.
I'll just have a small panic and go and see whar havoc I've just wreaked on my pride and joy [:0]
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Frog,
The bolts are meant to make dents in the eccentric, but not go right through.
This thread makes interesting reading and looks relevant.
www.sjscycles.com/forum/topic.asp?TOPIC_ID=973
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Many thanks for that julk!!
as you can guess my EBB was in the wrong position. Just spent half an hour putting it right by torchlight. I'd be surprised if anything works in the morning [:D]
TVM!!!
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Glad to report an uneventful, quite, ride into work this morning! Very many thanks for the advice chaps. It's greatly appreciated.
For me this raises a second question. Given the hammering the EBB shell takes by grace of the locking bolts deforming it's shape on each adjustment does this mean that when you buy a new chain should you also buy a EBB shell as well?
Price wise I'd have no real objection to that because previoiusly my chains were worn at 1000 miles and at £15 a pop that was five of them a year totalling £75 per annum on chains alone. As the current chain is now over 3000 miles old and still has wear to spare I'd still be in pocket at the end of the year.
In fact, this is the SRAM chain which came with the bike. I suppose if I invested in a Rohloff one at £35 that would work out even cheaper given the longer life expentancy of it
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quote:
does this mean that when you buy a new chain should you also buy a EBB shell as well?
No the EBB should outlast several chains - probably will never need to be changed during the life of the bicycle.
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Glad you sorted it frog, when you consider the number of moving parts a chain has it's hardly surprising how often it's the cause. I changed my SRAM chain after 12,000 miles, I've replaced it with a specific single speed one that should last longer!
Some of your questions about the chain adjustment and EBB come from your instinct that there’s an optimum tightness. I used to be of the same opinion, you'll soon realise that it isn't necessary to make small adjustments, the hub feels and works the same as long as the chain doesn’t restrict it and isn't going to fall off, that's quite a range.
As for needing to replace the EBB, here's Andy Blance's response to a similar comment in a review;
http://www.thorncycles.co.uk/cyclebiketestcomments.html
I've seen an EBB from a tandem that had the indents pre drilled, a good idea as you'd then have them as close as possible, if I ever need a new one I'll do that before fitting.
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The Click Returns!!!!
Not as loud as before but still in the same place (when the cranks are vertical).
I'm getting a priest in to exorcise it [}:)]
I'm going to have to wait for the weekend on this because searching for this isn't going to do my sanity any good if I've got to got to keep a torch aimed at the pertanant bit while I'm trying hard not to overtighten something.
As I've got it on each rotation I think I need to have a closer look at the pedals, crank and chainring bolts. I was impressed with the reduction of the click by reversing the chain. That's as near to witchcraft as I've seen with bike maintenance [:D]
Point taken PH with the reference to 'instinct'. This is one Skywalker who should RTFM a bit more [:I]
In the car for the next two days so only 30 or so miles riding before I can get to grips with it. It's a pity I can't recreate the problem while working on it in the shed [:(]
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Frog, I don't know what pedal/shoe combination you use but the clicking could be due to movement between the cleats and the pedal or even between the pedal body and spindle, as I once had. When the cranks are vertical the forces on each pedal change from a push to a pull and visa versa, so any play between shoe and pedal or within the pedal bearings will be most noticable. Interestingly I recently adjusted the chain on my Raven and not wanting to overtighten the EBB bolts, had one work loose allowing the EBB to move slightly with each revolution of the crank. This did not create an audible click but felt like a crank arm had come loose.
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I could have sworn I started this in General???
Anyway, the story so far. There is enough noise coming from in between my feet to give me the impression my BB is on it's way out. The clicks are more random now and come whatever the pressure on the pedals. Based on this I think I should swap out the BB as a first step.
Please can anyone tell me what Shimano BB the Thorn Raven Tour comes with? It looks to be a simple job of swapping out but has anyone any experience of pitfalls they've encountered doing this?
Finally, is there a BB which is the same size but higher spec I can put in instead?
I've got a Shimano crank removing tool (screw within a larger screw). Is this the right one for removing Thorn cranks?
Many Thanks in anticipation.
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According to the order sheet, they come with a Shimano UN53. That's pretty decent quality, part of the LX range, when replacing an extra fiver will get you a UN73 which is XT. Your crank puller will be fine. Before you invest in a new BB take the cranks off, clean and grease the square tapers and replace, some people say you shouldn't grease them but it's worked for me in the past, just another possibility!
I'd be surprised if it was the BB causing your problems, they usually last 10,000s of miles without any trouble. The only time I've had them fail it's been a grinding noise rather than a click and you could feel it through the pedals. As you say it's something to eliminate, without spending that much if you've already got the tools.
A cautionary tale - We were talking about odd noises on a club ride, somebody had had a drivtrain noise for weeks, it stopped when his handlebars snapped!
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Thanks PH! I'm driving myself into a bit of a corner here. I'd be delighted to get this problem fixed in one go because I use the bike 5 days a week for commute and recreation. I'm pretty sure that I've damaged the BB (see above for my botched attempt at adjusting the chain tension). All my woes have got progressively worse since then. I just want to have as much close at hand when I start to strip it all down tomorrow.
I'm looking at this as a self-inflicted wound rather than a breakdown of a component. Even if that wasn't the case I still class sealed BBs as consumable along with brake blocks and tyres. If you treat them right they'll last. If you don't - and I suspect I'm the guilty party here - you have to dip into wallet to learn from the mistake [:D]
That is a very scary tale of the handlebars [:0] I'm coming to the conclusion that cycling is good for you physically but can seriouly damage your mental health with worry over what's going to go wrong next [:D]
Thanks ROBO for the pedal/cleat advice. My pedals are speedplay frogs. Bearings are squirt through/mop up grease so they're always full of clean lubricant. The cleats are well tight into the shoe and the adjusting screw is fine. Having said that they'll get a once over tomorrow as well. I'm turning click, click into check, check - this could lead to OCD at this rate[}:)]
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If it is clicking not grinding it is unlikely to be the bb bearings but it could be the BB moving slightly in the EBB try removing and refitting the BB – clean the threads and lock tight them.
Is the BB a square taper or octolink model? – I have here of problems with splined (sp?) cranks cracking internally on the splines. (Hopefully this is not the case)
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Try looking here (http://"http://www.jimlangley.net/wrench/keepitquiet.html")
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Just when you think you've got it all sorted . . .
I was outside the bike shop at 09:00 this morning waiting for it to open. Got my UN53 (I asked if he had a Rohloff chain but the look I got back said it all).
Got home and started to gently strip the cranks etc down. Every thing came off with the necessary amount of gently, but firmly, applied pressure and cleaned up fine. Pedals were OK, cranks OK, chain I managed to drop in the muck a few times before I wrestled the link apart [:(].
It was when I got the EBB out I started to have trouble. The old star shaped spanner fitted a treat but there was no way I could generate the necessary torque to get it undone.[:0]
We'd moved house a few months ago and my bench, vice were binned and my stilsons were still in one of the many boxes dispersed about the house. So, I had to content myself with a good clean and regrease.
On the good side it gave me a chance to see just how meaty the EBB is and on the bad there were my two holes on the thin side of the wall staring back at me [:(]
The bike is back in one bit again and awaiting tomorrow's ride to see what's changed.
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Apologies if I’ve missed something obvious, why would you remove the EBB to remove the BB? I haven’t needed to do it yet, but I’d have thought leaving it in the bike and treating it as any other BB would be easier.
After all you've done, my money is still on it being the chain!
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My money is also on the chain. In my previous reply I said that I got a clicking noise after refitting the chain (I think I refitted it upside-down to it's original orientation). Refitting it fixed it.
A few days ago I got a rear puncture. After refitting the rear wheel I now have a similar clicking every couple of revolutions of the cranks (but not exactly every 2 turns). Uphill and under load you can hear/feel the click more. I haven't had time to inspect the chain yet but I'm expecting my new "Wipperman Connex Intrax 7Z1 Anti Rust Chain" from Wiggle this week (supposedly for hub-geared bikes).
I'll report back and let you know if it made a difference.
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Apologies for not replying earlier. It's been one of those weeks!!
The reason I removed the EBB as a whole was brought about by my fear of doing some damage to the rest of the bike. The stand I keep the bike in is just a display one and can't take much force. To remove the cranks I had either hand on pedal/ 12" 'T' bar on the extractor and the cross bar against the top of my head to balance the whole thing. The front wheel was jammed between a redundant fridge and weashing machine. Pressure was very gently applied so a constant balance was achieved. Having suceeded once I thought I was pushing my luck to try to generate the same amount of torque with nothing to balance the push against now the cranks were off. I had hoped that I could use a strap wrench as a windlass to remove the mounting nuts but that failed. The only thing missing was a drum roll and a ring master [:o)]
As I've got more than a few votes for the chain - and I've got the necessaries to do that - I think I'll have a crack at that next. Having said that the bike does seem a bit quieter this week but there are some regular clicks in with the random ones.
So, new chain, Rohloff 99-8, lubricant and chain tool ordered and we'll see what happens next [;)]
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New chain. Clicking gone.
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New chain, tool and oil arrived. Had loads of fun with the chain tool and nadgered up a few links at the end of the chain practicing with it. eventually got it sussed and then used the old chain as a measure for the new, matching link for link rather than just going for the overall length.
I think I've got it done fine, even taking the stiffness out of the joining link with a reverse one eight turn. I'm putting the chain tool and spare links in the tool kit so if I've made a real mess of it I can sit by the roadside and knit myself a new one out of the bits [;)]
looking forward for a quite ride in the morning [:D]
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The Thorn Raven Super Stealth is back!! [8D]
Had two days of super quiet commutes. The SRAM chain lasted 3428 miles - which is three times longer than I'd expect from the same chain fitted onto a derailleur bike. Despite the noise from it the chain gauge still said it was with tolerance and useable. Pity I can't pass it off to an owner of those strange open-air gear thingies (it's only 98 links). After all they're more used to the noise than I am [}:)][:D][:D]
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Just want to report another forum success. Like Frog I've been plagued with ICRPDS (irritating click on the right pedal downstroke syndrome) for the last three weeks. After checking all the usual things (cleaned the chain, eccentric adjustment, pedals, cranks, chain-ring bolts) I took freddered's advice and reversed and inverted the chain. Today, perfect silence -bliss! Very pleased as I've only done 1600 miles on the PC48 chain that came with the bike and I'd hoped to get at least double this on the rohloff based on previous chain wear on derailleur bikes.
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Agh, spoke to soon. The click returned after some serious hill work. Tried a new chain (PC68) but that didn't fix it so attention now focussed on the BB...
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I frequently suffer a similar noise, reversing the chain helped for a while but it soon came back.
I have found that after switching from Finish Line red (which worked well for my deraillieur bike) chain lube to the heavier/messier Finish Line green, the clicking noise occurs less frequently and usually goes away after lubing the chain.
Slightly OT - I'm surprised that some of you seem pleased with 3000 miles chain life from a PC48 chain and a rohloff, I would have hoped for much more as I used to get that mileage out of PC48's on my deraillieur bike.
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Might have solved the clicking.... Took the cranks off and aimed to remove the BB, but couldn't shift it and when really applying torque the eccentric moved. NB when the eccentric rotated the securing bolts scored a channel in the EBB-be really careful when trying to move the BB in situ! So, I removed the EBB clamped it in a vice and tried again -still couldn't shift the BB. On the assumption that the click was therefore not due to any movemment in the BB I greased everything else up and refitted. There was a bit of rust on the shell and the dents in the EBB looked a bit enlarged so this is my main suspect for the source of the click. This would be consistent with the fact that the click went away briefly when the original chain was turned and when I replaced the chain. I'll keep you informed.
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geocycle
What type of cranks are you using? The reason I ask is that Octolink cranks (esp. XT) are well known to creak, maybe you noise is coming from these? Alternatively it you think the noise is coming from the EBB / Frame interface it would be worth trying some PTFE tape (Pluming tape) around the EBB.
If I put my chain on upside-down it makes loads of noise the other way up it is almost silent. Why? – No idea but the difference is huge. The only explanation I can think of why the chain is nosier than on my derailer is that possibly I ran the chain too tight at some point in the past and it has deformed slightly. (I now run it very loose)
(For reference I use a SRAM P68 chain-5500miles; Blackspire DH chainring and Rohloff chain oil)
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Thanks Stutho, I may try the PTFE tape idea if the problem re-occurs. I am using a square sectioned spindle in thorn cranks. It is possible that greasing these up may have been the solution. However, when I reversed the original chain and also when I fixed a new one the problem stopped for a few days before returning, which leads me to think it is something to do with the EBB. At the moment the chain is quite tight but different tensions didn't seem to affect the irritating click. I've now got a PC68 chain and I am using finish line green oil, the PC48 chain had only done 1600 miles and is now a spare.
When you remove your BB do you leave the eccentric in place on the bike? As I mentioned above this resulted in the EBB moving and some damage.
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One more thought:
Another thing that might be worth a try is to remove the ebb and install it the wrong way round so the left is on the right. When you then tension the chain you will find that the bolts should bite on a ‘fresh’ area of the EBB (remember that the thick side of the EBB should always point down)
NB Long term it would be bad practice to leave BB in the wrong way round. So consider this a diagnosis procedure.
WARNING I have NOT tried this myself