Chain Saga

gummomarx

I'd recently been having trouble with my chain stuttering, slipping off teeth, particularly on the middle chain-ring.

My local repair man said I needed a new chainring and chain, so I sent him the spec for the bike (Giant Escape 0). He fitted them both and said he was 'fairly sure' the issue was sorted.

I've only been able to test the bike today (some days after the repair-man left the back back) but I now have similar issues on all chainrings.

Before I re-engage with the repair-man, I need to know if his having fitted a Shimano chain (114 links), instead of the original KMC X10 (114 links), could be causing the new issues.

sungod

if the old chain was worn, the cassette will be worn too, a new chain is likely to slip on an old worn cassette

Matthewfalle

Check the front chainrings for wear as well.

Brand of chain will make no difference at all.

cougie

Sometimes the chain needs a few miles to bed in on a slightly worn block

keef66

For the price of a 10 speed cassette I'd fit a new one. I'm surprised your repair man didn't suggest it.

gummomarx

Thanks for your advice - I'm going to replace the cassette myself - it doesn't look too difficult.

My cassette (Shimano Deore HG62 11-34) isn't wildly available. Do you know what I can replace it with to avoid any re-adjustment of the other elements in the drive?

keef66

Here you go http://www.chainreactioncycles.com/shim ... -prod52312

Slightly dearer than the original but available in 11-34 flavour if you want exactly the same spread of gears.

(I love the idea of a cassette being wildly available. Must be all those teeth....)

gummomarx

Thanks - I was going to correct my wide indiscretion but reckon it's more fun to leave it.

Matthewfalle

Gummomarx wrote:

Thanks for your advice - I'm going to replace the cassette myself - it doesn't look too difficult.

Take off wheel.

Take off q/r completely

Chain whip on old cassette

Casette removal tool in

Hold cassette with chain whip

Undo old cassette - this may take a big tug, then when you've finished that a bit of effort to undo the old cassette lock ring

Slide old cassette off, clean hub. Sometimes the cassette has bitten into the hub and it won't slide off - old screwdriver onto the back of the old hub, clout with hammer, cassettte will fall off.

If you fancy it, file off any burrs on the hub.

Grease hub, slide on new cassettte with any spacers

Grease threads for locking, do up lock ring to 40nm or another big tug then once you've finished that a big heft to do up

If you have to buy tools they will probably cost around £15 from CRC or similar and they will last for life.

Refit wheel, go off into the sunset and pull big skids.

Loads of YouTube vids if you get stuck.

Remember to hit old cassettte with a hammer and throw into next door's garden.

gummomarx

Thanks all, for you kind attention and good humour.

gummomarx

One more thing: it seems that replacing the chainrings is advisable too. How do I ID the individual chainrings on my crankset? https://goo.gl/5yQaG4

Matthewfalle

It goes by the BCD - compact are normally 110 bcd, normal 130 bcd.

You can use any manufacturer so long as the bcd and the bolt placement is correct.

Remember to hit old chainrings with a hammer and throw into next door's garden.

Matthewfalle

Remember as well that bizarrely it's sometimes cheaper to buy a whole new chainset than it us to buy the chains - check Planet X, CRC, Merlin Cycles, Ribble to name but a few.

keef66

Gummomarx wrote:

One more thing: it seems that replacing the chainrings is advisable too. How do I ID the individual chainrings on my crankset? https://goo.gl/5yQaG4

Thought you said bike repair bloke replaced the suspect chainring?

The chainrings themselves often have identifying marks on them if you want to go for exact replacements.

My Googling suggests your bike has a Shimano Deore FC-T 551 triple chainset? That's a MTB / trekking type so it uses a 4 bolt pattern with a 104mm BCD for the outer 2 rings and 64mm for the inner one.

But if all 3 need replacing it's often cheaper just to buy a new chainset complete...

DOH! a) I should've followed your link to your chainset and saved myself 5 minutes.
b) Matthew already suggested the last point
c) advice on BCD for separate rings still stands
d) Shimano replacements will have the required ramps and pins to help shifting up and down, but are often stupidly expensive and aftermarket Stronglight or similar will be 99% as good and half the price.

gummomarx

keef66 wrote:

But if all 3 need replacing it's often cheaper just to buy a new chainset complete...

I think I'll replace the cassette and see what happens but I did notice what looks to be a great deal on a complete crankset:
https://goo.gl/azhWW9

keef66

Actually googling for your individual Shimano chainrings it's clear they are cheaper than for road chainsets, so you may be OK

gummomarx

You reckon the complete crankset is the better option?

keef66

Not sure since your link doesn't work for me.

The Shimano rings I found on CRC started under a tenner for the inner ring, £12-15 for the middle and so on. So if all 3 are worn and you find a chainset for £50 it's probably a better option.

gummomarx

Thanks very much everyone, for your kind help and attention.