I think the rear derailleur on my bike has had it. It has become necessary to move the gear lever a couple of gears past the one I want when changing gear. I've given it a good clean and lube, checked the cable and stops adjustment to no avail. It is over ten years old and probably the cheapest the bike manufacturer could find at the time.
There seems to be at least two different types with different fittings available, with mounting brackets or fitted directly to the frame. Mine appears to be the latter, looks like this: www.ebay.co.uk/itm/BANKRUPT-REAR-BIKE-MECH-GEAR-DERAILLEUR-5-SPEED-F-I-S-INDEX-FALCON-NEW-/380638893870?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item589fd8972e
My bike's an old Peugeot hybrid. The current derailleur says 'dynadex falcon'.
Any advice or recommendations gratefully accepted. I don't need anything special. It's got six gears on the rear hub and I'm aware I'll have to count the teeth on the top and bottom gears. I don't want to order one to find it's not compatible. I've chain rivet removal and re-fitting tool.
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Change the cable before changing the rear mech.
Also, don't re-use the chain link you remove, get a replacement from a bike shop. Ends in tears otherwise.
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I have a couple in a box somewhere, but I have never known one to wear out - still sounds like a set-up issue to me tbh, some can be tricky to get right. Unless the spring is shot, I cant see what would make it do what you say, but I used to ride 6000 miles a year, never killed a spring and mine had 24 gears so lots of changing!
My first instinct would be to change the cable and go from there.
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Decent derailleurs (Campagnolo or the better quality shimano ranges) have an all metal parallelogram mechanism and are tough and resistant to wear. Plastic devices like that linked in the OP are another kettle of fish - the moving joints acquire play and the change gets mushy as the OP describes.
It's always worth replacing the cable first though and then methodically checking the adjustment.
Sheldon Brown has a good section checking etc:
sheldonbrown.com/derailer-adjustment.html
My concern with replacing an oldish indexed gear like that would be compatibility with the changer. Suggest checking with a bicycle shop or posting in the tech section at cyclechat.
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There's nothing to go wrong with a rear mech unless something is obviously broken. As said, change the cable.
Are the gears indexed or is it an old friction shift?
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>>Are the gears indexed or is it an old friction shift?
Indexed gears on a twist grip - I know, but it's what was available when I wanted a bike for a few miles to work and back each day, mudguards and carrier.
I've checked the cable and it's free with no sticking or fraying. The bottom of the derailleur's leaning towards the wheel, so I assumed the pivots have worn. It hasn't taken any knocks (to my knowledge).
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If it's out of alignment it might well be the problem then.
But it's probably a bit of everything - chain, sprockets, pivots, idlers, rider...
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The mech shown on your link is a five speed and won't work with six speed gears, you need to replace like with like. You've then got to find one that is compatible with the shifter as the cable pull between manufacturers varies.
Probably best to find a complete set.
I'm not being funny, but if the chain, cable and sprockets are also worn after ten years use it wouldn't cost that much more to buy a new bike of similar or better quality. It owes you nothing after a decade.
Last edited by: Robin O'Reliant on Wed 9 Oct 13 at 16:37
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Probably better still to get a new bike. For sure if these components are shonky so will the rest be...
Go on, give us a budget, you know we love a budget and for once I'll not say "Mondeo" !
;-)
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>> The mech shown on your link is a five speed and won't work with six
>> speed gears, you need to replace like with like. You've then got to find one
>> that is compatible with the shifter as the cable pull between manufacturers varies.
That would worry me too
>> Probably best to find a complete set.
>>
>> I'm not being funny, but if the chain, cable and sprockets are also worn after
>> ten years use it wouldn't cost that much more to buy a new bike of
>> similar or better quality. It owes you nothing after a decade.
>>
I enjoy repairing* and is not a chore to replace bits like this. If however I struggled with task or was paying a shop then I think Robin's got a point.
*Not this afternoon though when I found I'd ordered wrong size bottom bracket for the lad's Uni bike.
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Just in case you did decide that a new bike was the answer BT, I've used these people before. Some really good bargains to be had...
www.discountcyclesdirect.co.uk/catalog/index.php?CG_ID=2
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Thanks Humph, interesting link, but I'm thinking thieves are like magpies - go for shiny new stuff and mine's got the patina of age. Now I'm retired I only tend to use the bike a couple of times a week, into town and back, a couple of miles each way.
RO'R. I was aware that was a 5-speed shown in my link, I was just using it as an example, particularly the way it's mounted to the hub. I still don't understand the difference between direct mounts and those using a mounting bracket. It would appear that if using a mounting bracket, you need one unique to the frame?
I've been looking at this one, but can't see if it's suitable for mounting to my hub/frame: www.amazon.co.uk/Shimano-Rder-7SPD-Tx35-Direct/dp/B004T0GEFW/ref=sr_1_51?s=sports&ie=UTF8&qid=1381346903&sr=1-51&keywords=rear+derailleur
Looks like I'll have to pay local cycle shop prices.
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Is it worth taking to a bike shop and getting set up by a professional? Mrs FC is now into biking and running (York marathon next Sunday). A guy came to the house and gave the gears a good service. Loads of different adjustment points to get it just right.
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BT,
For the Shimano mech in the illustration to fit the frame needs to have an integral hanger on the end of the dropout. The mech in your first post slots over the spindle and is held to the frame by the bolt.
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My old bike, BT, is showing EXACTLY the same symptoms as yours; it's a 1980s Dawes Easy Street - an early attempt at a hybrid with 3 x 6 Shimano gears. Despite its age, it has probably done little more than 5,000 miles and now that I too am retired, I use it a couple of times a week to nip the 2 miles into town. It isn't especially attractive to thieves, unlike my 'Specialised' that I won't leave anywhere out of eyesight.
I can't believe that the gear mechanism is worn, despite the bike's age, and I reckon it's down to cleaning, possibly replacing the cable and having a proper adjustment by someone who knows what they're doing. I'm hoping to bring the subject up next time my mate comes over for a few days; he's a very keen cyclist and secretary of his local cycling club.
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Good link by Brompton.. www.car4play.com/redirect.php?http://sheldonbrown.com/derailer-adjustment.html
I've had poor changes to resolve a few times with used bikes bought for Mrs F and the teens. Usually going through lubrication/setting up as per that link works but sometimes I've found the chain (despite looking clean/lubricated) has lost the flex it needs to change gears properly.
A new chain can be the answer but often on an older bike the rear sprocket set seems to bed to the chain and that needs changing as well. In an extreme case the front chainwheel needed swapping too.
Another option is to buy a £50 Ebay bike (where you've established it changes gear fine) and then sell yours off for £30 as "needs gears setting up".
I fully agree re not wanting a shiny new bike. My old school mountain bike, despite riding superbly, is not attractive to the boys so I leave it everywhere unlocked.
Last edited by: Fenlander on Thu 10 Oct 13 at 09:02
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New derailleur arrived this morning: www.ebay.co.uk/itm/140988893861?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2648
Last of the big spenders?
Fitted it this afternoon. I mistakenly removed a chain rivet completely - it's been a long time since I last did that job, took me ages to correct it and then I found I'd routed the chain incorrectly through the new derailleur, so I had to break the chain again, !
I should've bought a new chain, I reckon the old one shouldn't be that flexible, sideways.
I've now got all the gears, when I want them. It changes as it should and the indexing's working properly too. I'll carry a screwdriver around for a little while as I expect it'll need some fine tuning as it beds in. I expect I'll upset everything when I get round to a new chain.
Last edited by: VxFan on Mon 27 Jan 14 at 12:44
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I know it's now too late for you bt, but it might help others in future. You don't usually need to break the chain to remove the derailleur.
If you unscrew the two bolts holding the jockey wheels in place, then the rear cage plate falls away and you can then remove the chain from the derailleur.
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Thanks for that Crocks, I'll try to remember when I get a new chain.
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>> I'll try to remember when I get a new chain.
But you do usually have to split a link to put a chain on or take it off.
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>> But you do usually have to split a link to put a chain on or take it off.
Do you? Only to shorten the chain surely. What has happened to those connecting links with a spring clip fitting in the grooved pins over a chainplate on the other side?
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AC, I know little about bikes and even I haven't seen one of those in 20 years.
I couldn't tell you why, though.
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>> even I haven't seen one of those in 20 years.
Neither have I, but I haven't looked for one.
It always worked perfectly well. Perhaps a keen modern cyclist can explain its apparent disappearance.
Actually reading below it seems the thing is still widespread.
Last edited by: Armel Coussine on Tue 15 Oct 13 at 02:00
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>> What has happened to those connecting links
>> with a spring clip fitting in the grooved pins over a chainplate on the other
>> side?
>>
Not compatible with derailleur gears, even old five speeds, as spring clip tends to foul the tensioner and/or sprockets.
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>> I know it's now too late for you bt, but it might help others in
>> future. You don't usually need to break the chain to remove the derailleur.
>>
>> If you unscrew the two bolts holding the jockey wheels in place, then the rear
>> cage plate falls away and you can then remove the chain from the derailleur.
The lovely old SunTour Cyclone derailleur had a cage that was open on the outside allowing the chain to be removed without dismantling. Some modern chains also have a 'magic link' to break them without a rivet tool. Don't trust them myself though - threw away the one that came with new chain for t'Lad's uni bike along with other surplus links.
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Some modern chains also have a 'magic link' to break them without a rivet tool. Don't trust them myself though - threw away the one that came with new chain for t'Lad's uni bike along with other surplus links.
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Safe as houses Brompt, that's all I ever used on my chains. With modern 9 and especially ten speed chains it is very easy to do some damage when you rejoin with a rivet tool.
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Agreed, I've always favoured SRAM chains with Power-Links, very well made and versions available for all types of riding.
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>>>I should've bought a new chain, I reckon the old one shouldn't be that flexible, sideways.
Bike chains for derailleurs should be very flexible sideways...
roadcyclinguk.com/riding/maintenance/maintenance-chain-checking-and-replacement-part-one.html/attachment/newchainoldchain
The test for wear is a gauge that measures length related to a certain number of links... or a quick diy check is to try and lift the chain off the front chainwheel.... ideally you shouldn't be able to see daylight under more than two teeth.
cdn1.coresites.mpora.com/rcuk/wp-content/uploads/2013/02/ChainLift-620x413.jpg
Last edited by: Fenlander on Tue 15 Oct 13 at 09:13
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When I get the new one, I'll take a photo of the old one. The rivet I removed had steps on it!
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As promised: tinyurl.com/nkko8zj
The old chain could form a 16" Dia circle, the new one 24".
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Changed the chain and all was fine - for a little while.
I've now found the cable has been acting as a cheese-wire on the plastic internals of the twist-grip shifter. I've opted for a lever replacement, which means the handlebar grips will be too short...........................................
Perhaps I should've gone for a whole new bike, rather than by instalments?
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Derailleur advice requested - Fursty Ferret
