Replacing worn chain and drive chain ?

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s2vmx
Posts: 81
Joined: 31 May 2010, 7:47pm

Replacing worn chain and drive chain ?

Postby s2vmx » 14 Dec 2012, 5:47pm

Having recently undertaken a cycle maintenance course, I am now aware of my worn out chain and broken derailer, on my old Dawes Galaxy. I would like to upgrade the worn parts and I'm aware its no point putting a new chain onto a worn chainset etc etc,
I am confused as to what parts are compatable - money is tight (I have another cycle for tours and longerdistances) - so could anyone suggest a groupset (if thats the word) - Chain, chainset, rear derailler, and cassette (if needed?) please - I've looked on the Spa site and they have their own brand triple chainsets @ Circa £35,

Please can any one assist - Ideally I would like to change the gear levers at the same time to STI's ??????

Many thanks

Stu

Brucey
Posts: 36122
Joined: 4 Jan 2012, 6:25pm

Re: Replacing worn chain and drive chain ?

Postby Brucey » 14 Dec 2012, 5:51pm

The Spa chainset is cracking value and will work with 5/6/7/8/9 speed transmissions.

However, everything else starts with the rear wheel you have; what it is, how wide it is and if you are keeping it, or going wider/different which often requires resetting the frame.

STIs are pricey; there are plenty of other shifters out there which will do the job (including the old ones, probably) if budget is tight.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Steve
Posts: 205
Joined: 2 Apr 2007, 1:42pm

Re: Replacing worn chain and drive chain ?

Postby Steve » 14 Dec 2012, 6:28pm

If money is tight then forget the STIs.

The parts on your bike will best determine what you replace them with. I'd say the starting point should be replacing your cassette with one that matches the number of sprockets (and sprocket sizes) on your existing one, which will mean you can keep your gear levers. (I assume it is a cassette rather than a screw-on freewheel.) The number of sprockets - 7/8/9/10? - will determine what type of chain you will need.

So that's cassette & chain replaced.

Is the derailleur actually past repair? It might be worth just getting some new jockey wheels if it's just a case of worn teeth.

It might be worth testing the bike at this point to see if the chain rings actually need replacing. If the old chain was very worn, it's likely that they will - though if you use the middle ring almost exclusively as many people do you might get away with replacing just that one, for about £20. If the other rings are worn as well it will almost certainly be cheaper to buy something like the Spa chainset at £35. BUT beware that this might mean you also need a new bottom bracket (this chainset probably needs one of a different length or fitting from your existing one) - so bear that in mind. That would mean at least another £15 or so and more faffing around.

There comes a point with many bikes when replacing a load of bits in one go simply becomes uneconomical or ludicrous, & you might as well just get another one, with everything you want already on it.

s2vmx
Posts: 81
Joined: 31 May 2010, 7:47pm

Re: Replacing worn chain and drive chain ?

Postby s2vmx » 15 Dec 2012, 6:30pm

Thanks for the responses - I'm not sure if the rear wheel is cassette or screw on freewheel - but pretty sure the derailleur is Kaput as its sitting rightnext to the rear cogs -bent and spring not functioning.
Will suss out sprockets sizes / numbers and possibly go from there although I may leave until spring, and gaining some knowledge, as I'm in two minds what to do.

Thanks

Stu-

andymiller
Posts: 1716
Joined: 8 Dec 2007, 10:26am

Re: Replacing worn chain and drive chain ?

Postby andymiller » 15 Dec 2012, 7:01pm

s2vmx wrote:I am now aware of my worn out chain and broken derailer, on my old Dawes Galaxy. I would like to upgrade the worn parts and I'm aware its no point putting a new chain onto a worn chainset etc etc,


You definitely shouldn't run a worn out chain on a new chainset, but a worn chain doesn't necessarily mean you have to replace everything else. For example the middle chainring may be a lot more worn than the outer. Check the condition of the chainrings - if any of the teeth look like shark's fins then you need to change it. I wouldn't mind betting that the cassette and chainrings are old and worn out (especially if they were run for a long period with a knackered chain), but it's worth checking before you write them off.

So far as compatibility is concerned the most critical bit is the cassette, SFAIK the front chainset isn't an issue. But the bible is here:

http://sheldonbrown.com/speeds.html

Bar-end or frame-mounted shifters have a lot of advantages for touring. Using them in non-indexed mode can save a lot of maintenance hassle.
Italy Cycling Guide - a resource for cycle touring in Italy.