Slipping Gears

[1second]

Your advice is not useful and smells just like bike-shop advice. A new bike is also a solution, may as well get a different wheel size whilst you're at it. However, most of us would prefer to hone in on the problem and only replace what's neccessary.

 

Just for clarity i am not an owner of or an employee of a bikeshop. My advice was given afer taking all of the comments and feedback into account. Whilst replacing the chainrings might be overkill the problem clearly smacks of a worn cassette. Whilst most people would feel that just repacingthis will work it is a MUST to also replace the chain. Through years of use the Cassette and chain wear in tandem and actually onlying end up working togther. I persoanlly run three chanins and rotate after every ride. It has prvoen to extend my cassette life four fold.

[jarek.pski]

Problem I experianced ths weekend is that one of the links on the chain won't bend, when I paddle and it gets to the cassette it jumps, when it gets to the jockey wheels same thing happens. Check the chain thoroughly....

[Johan Bornman]

Just for clarity i am not an owner of or an employee of a bikeshop. My advice was given afer taking all of the comments and feedback into account. Whilst replacing the chainrings might be overkill the problem clearly smacks of a worn cassette. Whilst most people would feel that just repacingthis will work it is a MUST to also replace the chain. Through years of use the Cassette and chain wear in tandem and actually onlying end up working togther. I persoanlly run three chanins and rotate after every ride. It has prvoen to extend my cassette life four fold.

 

You are digging yourself deeper into trouble.

 

Of course I didn't insunuate that you owned a bike shop. I made the point that bike shops, in ignorance or avarice, give out exactly the same poor advice.

 

I cannot see how you derived at your advice after summing up the rest of the comment. Most of them were shot from the hip.

 

A chain is replaced only if it is worn past 0.5%, no matter what the trouble at the cassette-end is.

 

Yes, replacing the chainrings is an overkill - an expensive one too. So why even suggest it?

 

I fail to see how running more than one chain will improve cassette life.

 

I suggest you search here for a thread or post with the keywords Everything You Need to Know about Bicycle Chains.

[tombeej]

1second, very brave of you to start a technical argument with Johan. Why waste your time with the peasants when you can climb straight into the ring with the big dude. Looking forward to what comes next

[The Drongo]

Go and buy a new chain a new cassette and new chainrings ....... Problem solved!

 

Uh, Dude..with all due respect, that sounds like " I bought a new BMW because the tyres were worn." Trust me, bike shops pick up on that attitude. They will end up selling you lots of stuff you do not necessarily need. Including bikes with big wheels.

 

The OP just gave us some clues:

 

He implies that his old bike had been standing, probably with the derailleur sitting in a tensioned position, and not at rest.

An old bike sitting in a garage or shed ends up suffering all kinds of abuse. Things get bent.

He did not say for how long, but the longer it sits, the worse it gets. Not only does the cable stretch, but the pulley cage tension spring can loose it's tension.

Depending on the derailleur this can sometimes be remedied by disassembly and setting the spring back in the second (tighter) tension hole.

The problem could also be that the pivot points on the derailleur are worn, and the lateral play, when the bike is under torque, causes ghost shifting.

It could be a bent derailleur hanger.

 

Point is that all of these problems should have been picked up and remedied by a competent mechanic, at a competent LBS.

Some gear change issues can not be replicated whilst the bike is on a stand, particularly with dual sus bikes. The mech needs to go out and ride it, and concentrate on testing the gears under load.

 

My advice to the OP at this point would be to go back to the LBS and request his money back if the LBS can not remedy the issue, or give him a no BS reason for not having done the job properly. The new CPA allows this. A bicycle mechanic is in the same position as a motor vehicle mechanic in this respect.

 

On the other hand, we are not aware of what the LBS may have said to him, that did not sound important to him at the time.

Edited May 4, 2011 by The Drongo

[The Drongo]

 

 

I fail to see how running more than one chain will improve cassette life.

 

 

Johan I have experimented with this theory.

 

For whatever reason the OP might do it (he does not specifically state), my conclusion is this:

 

Running multiple chains does not increase cassette life. If a specific make/model can only do 3000k's, then that is all it can do.

Sure, a clean drivetrain will count towards a longer cassette life.

 

However: (and I realise that part of what I tell you now you know already , but do so for those who may not.. )

 

Chains do not last as long as most cassettes. In the life of a cassette (In this instance an XT running XT narrow chains) three chains may be used. So when the chain is worn/'stretched', it is replaced, and then problems begin, with shifting and slipping under load etc.

 

Running two (pref 3) chains on rotation (swop out, clean and lube and store) every 3-400k's allows you to get to the end of a drivetrains life with no issues.

 

I am now at the end of exp. No 2. - running one chain full wear on a cassette, and than replacing with new. Thankfully I am at the end of it!

 

I will be reverting to the first option for as long as my legs continue to turn.

[Mojoman]

Johan I have experimented with this theory.

 

For whatever reason the OP might do it (he does not specifically state), my conclusion is this:

 

Running multiple chains does not increase cassette life. If a specific make/model can only do 3000k's, then that is all it can do.

Sure, a clean drivetrain will count towards a longer cassette life.

 

However: (and I realise that part of what I tell you now you know already , but do so for those who may not.. )

 

Chains do not last as long as most cassettes. In the life of a cassette (In this instance an XT running XT narrow chains) three chains may be used. So when the chain is worn/'stretched', it is replaced, and then problems begin, with shifting and slipping under load etc.

 

Running two (pref 3) chains on rotation (swop out, clean and lube and store) every 3-400k's allows you to get to the end of a drivetrains life with no issues.

 

I am now at the end of exp. No 2. - running one chain full wear on a cassette, and than replacing with new. Thankfully I am at the end of it!

 

I will be reverting to the first option for as long as my legs continue to turn.

How many K's have you done on the same cassette and chain in experiment number 2?

[The Drongo]

How many K's have you done on the same cassette and chain in experiment number 2?

 

In exp 1 - 3976k - 3 chains

 

In exp 2 - 2130k - 1 chain to about 1800'ish, 100% worn, new chain 330ks odd - ploblems!

[Burts]

Your advice is not useful and smells just like bike-shop advice. A new bike is also a solution, may as well get a different wheel size whilst you're at it. However, most of us would prefer to hone in on the problem and only replace what's neccessary.

[Lou Zealand]

A chain is replaced only if it is worn past 0.5%, no matter what the trouble at the cassette-end is.

 

Hi Johan,

Just out of curiosity, how would one (technically challenged) assess 0.5% wear!!

 

FWIW, I had issues with gear slipping (in low gears) and for R50 Cycle Lab reshaped the hanger and re-calibrated/adjusted the gears...

R500 seems pretty steep especially when there is no appreciable improvement