Advice on chain and poss chainring/cassette replacement, pls

[GingerSpeshster]

Hi all,

I've never changed the chain on my '92 Stumpy Comp, which is a sin I know, so it's time for me to get it sorted as I'm now getting back into biking and using this as a road hack.

Please see pics of chainrings and cassette attached. The chainring teeth do seem to be a little out of shape - moulded by a stretching chain? The cassette seems okay, but could that have suffered the same fate, i.e. tooth wear due to stretching chain?

As can be seen, rings are Specialized 46/36/24 and the cassette is 7 speed Hyperglide 12-28T. Groupset is Deore XT.

Which chain would you recommended and if you think I also need to change rings and cassette, which would be good options, pls?

Many thanks!

 

[1210tech]

From what I can see in the pictures the cassette and chain rings look fine to me, loads of life left in 'em, just get a new chain and go from there. I've just discovered the quick link chains such as SRAM or KMC, so much easier to wip on and off for maintenance/cleaning than having to get the chain link tool out to remove a pin

 

[Dead Rats]

as above, you may get some slip / suck but some of that could be reduced by carefully filing the worst of the chainring teeth.

that's the budget option, the best performance would obviously come from new rings and cassette as well but the teeth look ohhhhkayyy. Stronglight make good value 5 bolt rings, SRAM or Shimano for the cassette, and SRAM and KMC for the chain as stated would be my call

while you're at it spend a fiver on a chain wear indicator to make sure

 

[hamster]

Pop a new chain on it first. If it skips gears then replace the cassette. If there is then a funny low growling noise then the fronts need replacement. The outer looks badly worn to me.

Shimano cassettes have such low teeth that wear is hard to see - they usually skip before there is much visible.

 

[GingerSpeshster]

Many thanks for the advice and quick responses!

Please forgive my ignorance, but are Quicklink and Powerlink terms for the same link-system?

A quick look on eBay has thrown up SRAM 850, 870, 890 for between £11 and £20 and KMC X/Z82 for about £10.

Not wishing to start a SRAM v KMC battle, is it worth me spending £20 on the SRAM 890 or go for the KMC at a tenner?

Cheers!

 

[gtRTSdh]

First thing to do is measure your chain.

Put the chain in a combination of gears so that the chain is straight.
Apply some tension to the chain with the pedals by hand.
The links are 1/2" pitch so using a 12" rule a new chain will line up on 12" pin to pin, if your chain is measuring more than 12 & 1/16" then it needs changing.

 

[Dead Rats]

You can buy three KMC chains for about £20 if you shop around

 

[GingerSpeshster]

Thanks again, folks!

Chain measures 12 1/8 pin to pin! So time to order some KMCs!

Cheers again - I really appreciate it...

 

[xerxes]

Since reading this: http://www.cantitoeroad.com/chains I've been using Campagnolo Record 9 speed chains on both my 7 speed bikes and my 9 speed. SRAM chains appear to be made of cheese, Shimano not much better, Connex are best, but twice the price of the Campagnolo Record, so not as good vlaue.

I use a chain checker to check for wear on my chains regularly. As soon as it gets to 0.75% wear on my best bike I replace it and when either of my other two bikes get to 1% I replace the chain on my best bike with a new one and move it's chain onto one of the other bikes. That way, there's always a hardly worn chain on the bike with the cassette and chain rings that are most expensive to replace.

The width of a chain shouldn't make much difference to its durability, the side plates are same thickness, it's just that the rollers and pins in the centre are narrower. Also, it's a fallacy that chains "stretch", what happens is that the rollers and the lips on the inner link plate wear allowing more play, so the overall length of the chain increases:

Once the chain is elongated, the centre of the pins are no longer the same distance apart as the centre of the gaps between the teeth on the cassette and chain rings, so they start to wear the teeth to accomodate the greater length between the pins.

I can't really see the cassette in your pictures, but I'd say the 36t chainring is worn and the 46t is slightly, but not as badly, but I'd replace it if I was being fussy. I used Stronglight rings for my 5 arm crank, they looked quite similar to the originals and the price was reasonable: http://www.spacycles.co.uk/products.php?plid=m2b2s149p293

 

[GingerSpeshster]

Great - many thanks for that!

£14 for 46T seems pretty good to me.