New Chain
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Discussion

Seight_Returns

Original Poster:

1,640 posts

225 months

Wednesday 3rd March 2010
quotequote all
Apologies for the numpty question.

I need a new chain.

I have an 8 speed setup with a Tiagra rear derailleur and Deore front mech. A quick look at Wiggle shows a bewildering variety of chains from KMC, SRAM, Shimano and others. I know that chains come in different widths for 8 , 9 and 10 speeds but not sure if there are other factors I need to take into account other than width.

Can I just pick any 8 speed chain from any manufacturer and be sure it’ll work with my setup ?

Thanks in advance.

Gooby

9,269 posts

258 months

Wednesday 3rd March 2010
quotequote all
It is widely felt that the SRAM chains are superb. If they break they are easily joined with a power link. They are strong, light and reliable. The hollow pin chains are a little too delicate for montain climbing.

P-Jay

11,269 posts

215 months

Wednesday 3rd March 2010
quotequote all
Yeah SRAM chains FTW. I'd avoid the hollow pin ones and the cross-step ones, you're paying for a tiny reduction in weight and it's just something to break - anyway these aren't available on 8 speed chains.

In 8-Speed you've got the PC830/850/870/890 to choose from. The latter two are nickle plated for a tiny reduction in friction, they might be a bit more rust resistant, but if you keep them well lubed it doesn't matter.


Sucking eggs warning!

Also..... You don't say why you need a new chain, but if it's worn / keeps breaking you'll need a new cassett too. The chain / cassett wear togeather and a new chain will just skip/jump on an old cassset under any load.

Shimano are best for cassets IMHO. I use XT or Saint/SLX spec ones, again not available in 8 speed. Ether the HG40 or LX 8 speed cassettes will be fine...

You'll also need a cassette tool and chain whip to fit them.

Gnarlybluesurf

263 posts

200 months

Wednesday 3rd March 2010
quotequote all
A mechanic at Evans told me a good tip was to replace your chain every 6 months to prolong the life of your cassette and avoid having to change it all together... saving money over the longterm.

Never done it myself.... does anyone else do this?

Gooby

9,269 posts

258 months

Wednesday 3rd March 2010
quotequote all
Gnarlybluesurf said:
A mechanic at Evans told me a good tip was to replace your chain every 6 months to prolong the life of your cassette and avoid having to change it all together... saving money over the longterm.

Never done it myself.... does anyone else do this?
After a 3 months my chain is kaput anyway!

pdV6

16,442 posts

285 months

Wednesday 3rd March 2010
quotequote all
Depends on riding conditions, obviously. If you want to be sure, invest in a chain measure and replace the chain when it gets to the minimum wear limit.

Nick_F

10,598 posts

270 months

Wednesday 3rd March 2010
quotequote all
Get a chain wear gauge, replace chain at 0.75% worn, replace cassette every second chain.

Gazzab

21,572 posts

306 months

Thursday 4th March 2010
quotequote all
My chains last 6 months, rear cassette and front rings a year. And that is only 1 2hr ride a week.
I guess it is all down to terrain, conditions and riding style. I am in the White Peak - so lots of mud and fine grit. Lots of steep hills. Lots of granny gear climbs with acceleration over rocky areas.

Seight_Returns

Original Poster:

1,640 posts

225 months

Thursday 4th March 2010
quotequote all
Thanks very much - SRAM PC850 ordered.

Already have a new HG40 cassette ready to fit and have a lockring tool and chain whip (although have never used either) but seems straightforward enough from Sheldon Brown's site.

cliff123

458 posts

266 months

Friday 5th March 2010
quotequote all
Nick_F said:
Get a chain wear gauge, replace chain at 0.75% worn, replace cassette every second chain.
A chain wear gauge? Is there such a thing?
Replace chain at 0.75% worn? Are you serious? Do you mean 75% worn?

How do you judge a chains wear? Other than knowing it's worn out when it snaps? I wash and oil my bike and chain after every ride so hope that's looking after it, but have no idea on how you would judge how worn a chain is.

Gazzab

21,572 posts

306 months

Friday 5th March 2010
quotequote all
The chain tool measures the 'stretch' of the chain.

cliff123

458 posts

266 months

Friday 5th March 2010
quotequote all
Nick_F said:
Get a chain wear gauge, replace chain at 0.75% worn, replace cassette every second chain.
A chain wear gauge? Is there such a thing?
Replace chain at 0.75% worn? Are you serious? Do you mean 75% worn?

How do you judge a chains wear? Other than knowing it's worn out when it snaps? I wash and oil my bike and chain after every ride so hope that's looking after it, but have no idea on how you would judge how worn a chain is.

Gooby

9,269 posts

258 months

Nick_F

10,598 posts

270 months

Friday 5th March 2010
quotequote all
cliff123 said:
Nick_F said:
Get a chain wear gauge, replace chain at 0.75% worn, replace cassette every second chain.
A chain wear gauge? Is there such a thing?
Replace chain at 0.75% worn? Are you serious? Do you mean 75% worn?

How do you judge a chains wear? Other than knowing it's worn out when it snaps? I wash and oil my bike and chain after every ride so hope that's looking after it, but have no idea on how you would judge how worn a chain is.
See above or:

http://www.chainreactioncycles.com/Models.aspx?Mod...

You use the .75% side first; hook one end into the chain and see whether or not the other will drop through: if it does then the chain is at least .75% worn/stretched and it's time to think about replacing it.

Use the 1% side, and if that drops through then you've very likely worn the chain to the point where it in turn will have worn the cassette and possibly the chainrings to the stage where these won't work well with a new chain and may need replacing too.

New chain on cogs that have been worn into hooks by badly stretched old chain = chainsuck and rapid wear/breakage of new chain.

Chains should be treated as consumables.

Edited by Nick_F on Friday 5th March 12:51

pdV6

16,442 posts

285 months

Friday 5th March 2010
quotequote all
cliff123 said:
How do you judge a chains wear? Other than knowing it's worn out when it snaps? I wash and oil my bike and chain after every ride so hope that's looking after it, but have no idea on how you would judge how worn a chain is.
The rollers between each link gradually wear, meaning that the links can pull slightly further apart from one another.
The end result is a chain that appears to have stretched, i.e. if you took it off and pulled it taut, it would cover a longer distance than when new.

Saddle bum

4,211 posts

243 months

Sunday 7th March 2010
quotequote all
Gnarlybluesurf said:
A mechanic at Evans told me a good tip was to replace your chain every 6 months to prolong the life of your cassette and avoid having to change it all together... saving money over the longterm.

Never done it myself.... does anyone else do this?
I used to ride Campag chains, but now use KMC 'cos it's convenient to use the split links and remove the chain for cleaning.

I never do more than 1500-2000 miles on a chain and I have never had to replace a cassette.