Skipping chains...

wotnoshoeseh

OK
Bought a brand new Defy (2014 model) at end of January with 105 5700 and Tiagara cassette, R500 crankset, KMC X10 chain - rode it through February and March - then with the unusual good weather in April, went to summer bike.
I have been back riding the Defy now for the past 2 months. Total mileage on Defy 1300-1400 miles max. (Edit - 1410 miles or so)

But now I have a chain skipping over sockets - 2nd and 3rd lowest (smaller cogs).
Checked chain - not quite at 0.75% but close - KMC model X10 but not sure of variant.

No way should this drivetrain be skipping with only this amount of miles?? Anyone got any thoughts / advice?
Do I just bite the bullet and replace chain and cassette?

Zerotails99

What do you mean by skipping?

Maybe the barrel adjuster needs adjusting.

wotnoshoeseh

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19727629#p19727629]Zerotails99[/url] wrote:

What do you mean by skipping?

Maybe the barrel adjuster needs adjusting.

No changing and shifting is spot on - should have been clearer - sorry.
It's only on the couple of cogs on the cassette toward the bottom of the cassette, and it's consistent with worn chain / teeth on the cassette.
The bit that is throwing me is that there's only 1400 miles on the chain and cassette.

darkhairedlord

Could be the upper pulley wheel on the rear derraileur sticking. It runs on a bush and should slide axialy. Otherwise it either needs new chain or cassette, I would swap out both.

pblakeney

You've checked the chain. Good.
Next check the jockey wheels for gunk build up.
If that's not it, check the cable condition.
One of mine recently did that and the cable finally snapped in the levers.

rower63

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19727618#p19727618]wotnoshoeseh[/url] wrote:

...But now I have a chain skipping over sockets - 2nd and 3rd lowest (smaller cogs).
Checked chain - not quite at 0.75% but close - KMC model X10 but not sure of variant.

No way should this drivetrain be skipping with only this amount of miles?? Anyone got any thoughts / advice?
Do I just bite the bullet and replace chain and cassette?

If you're a "grinder" (like me) and tend to stick to the same hard sprockets, it's likely you'll have concentrated the wear on just 2 sprockets. Furthermore if you've done a lot in the wet and not often cleaned the chain or sprockets then 1500 miles is easily enough to get 0.75% wear. That amount of chain elongation concentrated on just a couple of sprockets with lots of grinding-paste (the black gunky stuff) present will have worn them to the point where it will skip. My own winter bike tends to start skipping at around that level of wear.
Sounds like a new chain/cassette to me
However, I have also had a case where a sprocket was cracked, and every time I selected that gear the chain went crazy skip-skip-skip. Worth removing the cassette and checking for that, it's unlikely but worth always checking the cheapest things first!

chris_bass

given you were riding it January to March wear will happen quicker. Depending on how clean you left it when you packed it away for the summer it could be a few stuck links in the chain.

Schoie81

I have a Defy (albeit a 2013 model and yours is higher spec...) and I get this happening with mine (not that I'm saying that means its a model-specific problem..). In fact, mine is doing it at the moment. I don't know if my diagnosis makes any sense in practice, but I've put it down to 'gunk' in the cable sleeves and as the temperature drops at this time of year, it thickens up and stops the cables moving as freely as they should. It seems to me that it happens more in winter when its colder, but that could be a coincidence. That might be complete rubbish, but a good clean of the cables and sleeves/outers and then lubricating the cable has always sorted it out for me. Worth giving it a go before you go replacing any parts....?

pirnie

A very slightly bent mech hanger maybe?

keezx

Skipping has nothing to do with shifting performance.
The skipping cogs and/or chain are worn-out,whatever reason.

dj58

Before you put the bike in storage for the summer, did you thoroughly clean the transmission? Take the chain off and give it a damn good clean/re-lube. While the chain is off check the high/low limit and B-tension screw settings, check the gear hanger alignment, may have been knocked/bent in storage?

As mentioned clean and lube the RD cable and RD jockey wheels. If skipping still persist you could try a new cassette first, CS-4600 cassettes can be bought for £11-12, quid X10-EL nickel plated chain around £20 - £23. Sometimes a new chain will skip on an old cassette but will bed in, if the cassette is not excessively worn. Depends if you can put up with it skipping in the interim period, however if you need to replace the cassette, I'd replace the chain also and start again.

I've read many times on here that you should get three chains to a cassette with regular cleaning/lubricating and not letting the chain wear past 0.75 point.

wotnoshoeseh

OK - for the sake of £25 I bought a new chain and cassette today and refitted. I noticed quite a bit of wear on the second from last cog on the cassette, so maybe I'm just pushing too hard (lol)....
I also spotted when I had the wheel out that the derailleur hanger was loose so tightened that up too. Although tbh, once the QR is done up I don't think the loose derailleur hanger would have been a contributing factor.... (I'm sure this will be corrected though..)..
So new chain (5700) and new cassette (4600) now fitted - tomorrow morning will be proof of the pudding... nice and shiny though..

Thanks all...

D

keef66

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19728927#p19728927]wotnoshoeseh[/url] wrote:

OK - for the sake of £25 I bought a new chain and cassette today and refitted. I noticed quite a bit of wear on the second from last cog on the cassette, so maybe I'm just pushing too hard (lol)....
I also spotted when I had the wheel out that the derailleur hanger was loose so tightened that up too. Although tbh, once the QR is done up I don't think the loose derailleur hanger would have been a contributing factor.... (I'm sure this will be corrected though..)..
So new chain (5700) and new cassette (4600) now fitted - tomorrow morning will be proof of the pudding... nice and shiny though..

Thanks all...

D

Presumably you have shortened it to the correct length?