|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Chain Troubleshooting
Some of you may remember me asking for advice about touring bikes a few
weeks ago. The good news is that I currently have a Dawes Super Galaxy on order. The bad news is that it will be a few more weeks before my LBS get it. In the meantime I am using a somewhat unloved, second-hand, cheap 'mountain bike'. However, twice now the chain has come off when I am riding it and I am planning on diagnosing and repairing it myself if I can, especially because the chance to tinker on a ropey old bike has to be better than playing with a new, expensive one. In what order should I be looking into the problem. At the moment I think that I should check the chain for stretching, wear or damage, check the cranks and cassette for wear and then check the front and rear derailleurs. Is this the sort of work that a newcomer to bicycles can carry out with the aid of a good book and web guides or should I just take it to my LBS and start with something simpler? Thanks. Simon |
Ads |
#2
|
|||
|
|||
Chain Troubleshooting
"Simon Wolf" wrote in message news:1hwzqx3.f2t6hpnb83v6N%simon@ottersoftwaredotc om.invalid... Some of you may remember me asking for advice about touring bikes a few weeks ago. The good news is that I currently have a Dawes Super Galaxy on order. The bad news is that it will be a few more weeks before my LBS get it. In the meantime I am using a somewhat unloved, second-hand, cheap 'mountain bike'. However, twice now the chain has come off when I am riding it and I am planning on diagnosing and repairing it myself if I can, especially because the chance to tinker on a ropey old bike has to be better than playing with a new, expensive one. In what order should I be looking into the problem. At the moment I think that I should check the chain for stretching, wear or damage, check the cranks and cassette for wear and then check the front and rear derailleurs. Is this the sort of work that a newcomer to bicycles can carry out with the aid of a good book and web guides or should I just take it to my LBS and start with something simpler? Yes, it's a good job to start on. Does the chain come off at the front or back - does it come off when changing gear? Park Tools and Sheldon Brown are two good sites for info on maintenance. Peter |
#3
|
|||
|
|||
Chain Troubleshooting
peter-potato wrote:
"Simon Wolf" wrote in message news:1hwzqx3.f2t6hpnb83v6N%simon@ottersoftwaredotc om.invalid... Some of you may remember me asking for advice about touring bikes a few weeks ago. The good news is that I currently have a Dawes Super Galaxy on order. The bad news is that it will be a few more weeks before my LBS get it. In the meantime I am using a somewhat unloved, second-hand, cheap 'mountain bike'. However, twice now the chain has come off when I am riding it and I am planning on diagnosing and repairing it myself if I can, especially because the chance to tinker on a ropey old bike has to be better than playing with a new, expensive one. In what order should I be looking into the problem. At the moment I think that I should check the chain for stretching, wear or damage, check the cranks and cassette for wear and then check the front and rear derailleurs. Is this the sort of work that a newcomer to bicycles can carry out with the aid of a good book and web guides or should I just take it to my LBS and start with something simpler? Yes, it's a good job to start on. Does the chain come off at the front or back - does it come off when changing gear? Park Tools and Sheldon Brown are two good sites for info on maintenance. Peter Hi Peter. It comes off at the front and it does happen when trying to change gear. Also, after changing gear up the chain often sounds very rough but changing two gears up and one down seems to solve this. Simon |
#4
|
|||
|
|||
Chain Troubleshooting
Simon Wolf wrote on 22/04/2007 22:24 +0100:
Hi Peter. It comes off at the front and it does happen when trying to change gear. Also, after changing gear up the chain often sounds very rough but changing two gears up and one down seems to solve this. Sounds like the deraileurs need some adjustment rather than the chain etc. The Shimano instructions that come with a new deraileur are pretty good for setting one up but otherwise http://sheldonbrown.com/derailer-adjustment.html is excellent too. -- Tony "The most savage controversies are those about matters as to which there is no good evidence either way." - Bertrand Russell |
#5
|
|||
|
|||
Chain Troubleshooting
Tony Raven wrote:
Simon Wolf wrote on 22/04/2007 22:24 +0100: Hi Peter. It comes off at the front and it does happen when trying to change gear. Also, after changing gear up the chain often sounds very rough but changing two gears up and one down seems to solve this. Sounds like the deraileurs need some adjustment rather than the chain etc. The Shimano instructions that come with a new deraileur are pretty good for setting one up but otherwise http://sheldonbrown.com/derailer-adjustment.html is excellent too. Lovely, thanks Tony. |
#6
|
|||
|
|||
Chain Troubleshooting
Following on from Simon Wolf's message. . .
(1) Front gear adjustment is 'easy'. A book from the library is worth getting because (a) it will tell you about this issue and (b) lots of other things that will probably be irrelevant or far too involved... ....but good background information for the next time. (2) There are basically two failure modes for front chain wheels (a) Chain 'farts' under pressure. The gear wheel is worn after many years of service. (Possibly the chain is very worn as well.) Solution = Replace gear wheels. (b) Chain doesn't move properly between gears. To deal with 2b (this is the common situation - I had it today) there are two _types_ of adjustment each with two sub-adjustments. You may have to jiggle between these to get to the end result. Limits: On the lever arm that is pulled out from the frame by the gear cable should be two screws. One sets the limit of inside travel and the other the outer. Experiment. For example suppose you were changing down into bottom gear and the chain falls off! Tweak the appropriate screw to move the limit out. (You may be able to feel the lever assembly moving as you tweak.) Cable: From your description (which was better than I could put into words) when you change it doesn't quite happen. There are often two ways to adjust this. The rough and ready method which is by trapping the cable at a certain point in the actuating lever (usually involving an Allen key) which gives a rough setting. (set up in 1st). The second way is by a fine-tune mechanism on the gear shifter. On mine I turn a knobbly nut surrounding the cable as it goes into the shifter mechanism. Learn which way is which (twiddle while fondling gear mechanism). Experiment. My guess is that you don't know about the fine-tune gear adjusters. 5 minutes of experiment without tools and your problem is solved. [NB If not then please call again] -- PETER FOX Not the same since the e-commerce business came to a . www.eminent.demon.co.uk - Lots for cyclists |
#7
|
|||
|
|||
Chain Troubleshooting
"Peter Fox" wrote in message ... My guess is that you don't know about the fine-tune gear adjusters. 5 minutes of experiment without tools and your problem is solved. [NB If not then please call again] I don't think it's true on all derailleurs, but the ones on my bike are 'open' in that you can see the adjusting screws going through them and see exactly how they work. This is particularly useful if you can't remember which is the high and which is the low one! -- peter Cheap train tickets database http://www.petereverett.co.uk/tickets/ Email sent to this address is generally deleted upon arrival Visit website if you want to contact me |
#8
|
|||
|
|||
Chain Troubleshooting
in message 1hwzstp.18he5onx4ixqmN%simon@ottersoftwaredotcom. invalid,
Simon Wolf ') wrote: peter-potato wrote: "Simon Wolf" wrote in message news:1hwzqx3.f2t6hpnb83v6N%simon@ottersoftwaredotc om.invalid... Some of you may remember me asking for advice about touring bikes a few weeks ago. The good news is that I currently have a Dawes Super Galaxy on order. The bad news is that it will be a few more weeks before my LBS get it. In the meantime I am using a somewhat unloved, second-hand, cheap 'mountain bike'. However, twice now the chain has come off when I am riding it and I am planning on diagnosing and repairing it myself if I can, especially because the chance to tinker on a ropey old bike has to be better than playing with a new, expensive one. In what order should I be looking into the problem. At the moment I think that I should check the chain for stretching, wear or damage, check the cranks and cassette for wear and then check the front and rear derailleurs. Is this the sort of work that a newcomer to bicycles can carry out with the aid of a good book and web guides or should I just take it to my LBS and start with something simpler? Yes, it's a good job to start on. Does the chain come off at the front or back - does it come off when changing gear? Park Tools and Sheldon Brown are two good sites for info on maintenance. Peter Hi Peter. It comes off at the front and it does happen when trying to change gear. Also, after changing gear up the chain often sounds very rough but changing two gears up and one down seems to solve this. Inside or outside? Falling off the outside is a matter of adjusting the high limit screw on the front derailleur inwards (clockwise) a little - too much and you won't be able to get onto the big ring. With a trimmable front (old friction shifters or top-end Campagnolo) you can recover an off-the-outside chain as you ride, simply by trimming back a little. Off the inside is trickier. It's usually a symptom of poor chainline and again it's worse on Shimano indexed systems; but off-the-inside is usually not recoverable without getting off anyway. Screw in the low limit screw on the front derailleur (clockwise) a little, but this is a sensitive adjustment. If you can't get it to work any other way, fit a dogtooth. http://www.mybikeholiday.com/photo_b...essory,400.JPG -- (Simon Brooke) http://www.jasmine.org.uk/~simon/ ;; If God does not write LISP, God writes some code so similar to ;; LISP as to make no difference. |
#9
|
|||
|
|||
Chain Troubleshooting
Peter Fox wrote:
Following on from Simon Wolf's message. . . (1) Front gear adjustment is 'easy'. A book from the library is worth getting because (a) it will tell you about this issue and (b) lots of other things that will probably be irrelevant or far too involved... ...but good background information for the next time. Got one, well a couple actually. (2) There are basically two failure modes for front chain wheels (a) Chain 'farts' under pressure. The gear wheel is worn after many years of service. (Possibly the chain is very worn as well.) Solution = Replace gear wheels. (b) Chain doesn't move properly between gears. This is my problem. To deal with 2b (this is the common situation - I had it today) there are two _types_ of adjustment each with two sub-adjustments. You may have to jiggle between these to get to the end result. Limits: On the lever arm that is pulled out from the frame by the gear cable should be two screws. One sets the limit of inside travel and the other the outer. Experiment. For example suppose you were changing down into bottom gear and the chain falls off! Tweak the appropriate screw to move the limit out. (You may be able to feel the lever assembly moving as you tweak.) Thanks peter. This solved my problem. Cable: From your description (which was better than I could put into words) when you change it doesn't quite happen. There are often two ways to adjust this. The rough and ready method which is by trapping the cable at a certain point in the actuating lever (usually involving an Allen key) which gives a rough setting. (set up in 1st). The second way is by a fine-tune mechanism on the gear shifter. On mine I turn a knobbly nut surrounding the cable as it goes into the shifter mechanism. Learn which way is which (twiddle while fondling gear mechanism). Experiment. I twiddled with the knob for a while and ended up with a situation where the second smallest cog was aways skipped going both up and down through the gears to I took my bike to my LBS for some advice about this once I had re-aligned the deraliers and they think that it might be caused by the gear levers. As my new bike is only a few weeks away I think that I will live with the problem and then what I have some extra cash in a few months I will replace the whole gear system myself as a project. My guess is that you don't know about the fine-tune gear adjusters. 5 minutes of experiment without tools and your problem is solved. [NB If not then please call again] Thank you for the advice. At least I should now be able to ride without the chain falling off all the time! |
#10
|
|||
|
|||
Chain Troubleshooting
Simon Brooke wrote:
in message 1hwzstp.18he5onx4ixqmN%simon@ottersoftwaredotcom. invalid, Simon Wolf ') wrote: peter-potato wrote: "Simon Wolf" wrote in message news:1hwzqx3.f2t6hpnb83v6N%simon@ottersoftwaredotc om.invalid... Some of you may remember me asking for advice about touring bikes a few weeks ago. The good news is that I currently have a Dawes Super Galaxy on order. The bad news is that it will be a few more weeks before my LBS get it. In the meantime I am using a somewhat unloved, second-hand, cheap 'mountain bike'. However, twice now the chain has come off when I am riding it and I am planning on diagnosing and repairing it myself if I can, especially because the chance to tinker on a ropey old bike has to be better than playing with a new, expensive one. In what order should I be looking into the problem. At the moment I think that I should check the chain for stretching, wear or damage, check the cranks and cassette for wear and then check the front and rear derailleurs. Is this the sort of work that a newcomer to bicycles can carry out with the aid of a good book and web guides or should I just take it to my LBS and start with something simpler? Yes, it's a good job to start on. Does the chain come off at the front or back - does it come off when changing gear? Park Tools and Sheldon Brown are two good sites for info on maintenance. Peter Hi Peter. It comes off at the front and it does happen when trying to change gear. Also, after changing gear up the chain often sounds very rough but changing two gears up and one down seems to solve this. Inside or outside? Falling off the outside is a matter of adjusting the high limit screw on the front derailleur inwards (clockwise) a little - too much and you won't be able to get onto the big ring. With a trimmable front (old friction shifters or top-end Campagnolo) you can recover an off-the-outside chain as you ride, simply by trimming back a little. Off the inside is trickier. It's usually a symptom of poor chainline and again it's worse on Shimano indexed systems; but off-the-inside is usually not recoverable without getting off anyway. Screw in the low limit screw on the front derailleur (clockwise) a little, but this is a sensitive adjustment. If you can't get it to work any other way, fit a dogtooth. http://www.mybikeholiday.com/photo_b...essory,400.JPG Thanks Simon. Some derailleur tweaking solved the problem (for now) and it was coming off on the inside. I also have a problem with the rear cassette where gears skip but this apparently is most likely linked to my Shimano gear selector and I can live with it until my new bike arrives. Simon |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Block chain, roller chain, shaft-drive, wood-rim, and world's weirdest chain | [email protected] | Techniques | 8 | April 15th 07 01:50 AM |
HID troubleshooting help | Mark Atanovich | Techniques | 4 | October 31st 06 03:14 PM |
The chain slips seldom when speeding up; can this break the chain? or do I have to line up the back sprockets? | Iván C. Filpo | Techniques | 4 | July 20th 06 04:44 PM |
troubleshooting my seat | [email protected] | General | 4 | October 18th 05 05:49 PM |
troubleshooting KH onza hub/cranks? | onewheeljoe | Unicycling | 5 | July 22nd 05 03:30 PM |