# Clunky gear changes?



## idividebyzero (Sep 25, 2014)

I just got an older Iron Horse MKIII that is basically a fixer upper, I got it for cheap though so there are some things Id like to upgrade.

One thing Im not a fan of is the rear gear changes just kind of clunk into place. What seems to be happening is the chain links dont line up with the cassette teeth right away. Is this caused by the derailer? Chain? Cassette? 

The chain is in poor to ok condition, a little rust and I dont know if its stretched or not, none of the links are stuck but they arent the smoothest bending in the world, I plan on getting a new one soon regardless. The Derailer is a cheap Shimano Deore though, do they normally clunk the chain into the gear?


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## rangeriderdave (Aug 29, 2008)

The first thing to check are the cables clean and lubed. If they are dirty ,there can a lag that would cause a clunk. The chain or the cassette could worn ,which would make it look like they don't line up. The chain should measure close 12" pin to pin. Deore is a dissent derailleur. Before you dump a lot of $ into it ,what do you want from the bike? Clean the chain ,lube it ,then see how it is. You should be aware that just replacing the chain can cause problems with shifting.


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## Phinias (Aug 28, 2014)

Sounds like chain to me. My nubby self would first replace any chain that has rust on it and also sounds like it is pretty stretched out too. $20-30 bucks for a good chain won't brake yeah and will go along way to helping you out. While you are at check on replacing the cables and liners think someone mentioned a high quality kit at REI for another $40 or so. Most likely both will be upgrades over what you have now as well. Then of course adjust the cables and you should be good to go.

Mot is also my understanding that Deore level gear is generally plenty solid, so less expensive, yes... Cheap no... Just serviceable.


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## Guest (Sep 26, 2014)

Pretty common for the rear-most section of der cable to wear out and bind. New cables are always a good idea on an older bike. Also, the best specialty tool you can own is a quality chain stretch gauge. They're cheap and will prevent other component damage.


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## idividebyzero (Sep 25, 2014)

for some reason I never thought of using a ruler to measure the chain, just did a measure and 12 links is at 12 1/16", maybe a little bit past 1/16. So it is stretched out. Hopefully getting a new chain will give slick gear changes like in this video How to set up your gears and rear mech - YouTube (on mine the chain gets hung up on the teeth sometimes and skips gears entirely when changing really fast)

I'll pick up a couple new cables as well for front and rear


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## Mr Pig (Jun 25, 2008)

If the chain is stretched there's a good chance you will not be able to change just the chain. The cassette and chain rings will probably be worn too, budget for replacing the lot!

If the dérailleur is still reasonably tight, doesn't wobble around too much or hang in at an angle, it will probably be fine. Just clean and lube it.



Phinias said:


> My nubby self would first replace any chain that has rust on it


Rust doesn't mean anything on a chain. A brand new chain can get rusty on the outside if the conditions are right but still be perfectly fine. Chain stretch is the only reliable indicator of chain wear.


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## eb1888 (Jan 27, 2012)

Cables alone often aren't the sole problem, housing and ferrules should also be changed. If you want to get better than new shifting feel a $19 kit from REI will do it. Slick coated stainless cables and lined housing. Running the cable full length is also good for smoothness with a larger loop at the rear. You will need some extra housing off their bulk roll for this. You eliminate a lot of cable openings and ferrules with full length.
Novara Shift Cable Kit at REI.com
Use good cutters. Superglue the cable before you cut. Open and smooth the housing cut ends. A couple drops of silicone lube help.


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## kapusta (Jan 17, 2004)

First thing to do with a fixer-upper is get new shifter cables and housing, especially if the derailleur response is slow. You don't need anything fancy, you can just get whatever is an sale.

Go to some place like Park tools website for instructions on how to set up a rear derailleur.

However, before you do anything to that bike, make sure the rear triangle is not cracked. Many years of the MKIII were very prone to cracking in both the front and rear triangles. Go look at some older threads on this in the Iron Horse forum. 

Other than the cracking issue, the MKIII was an amazing bike frame IMO. I loved mine (until it cracked).


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## jeffj (Jan 13, 2004)

kapusta said:


> First thing to do with a fixer-upper is get new shifter cables and housing, especially if the derailleur response is slow. You don't need anything fancy, you can just get whatever is an sale.
> 
> Go to some place like Park tools website for instructions on how to set up a rear derailleur.
> 
> ...


Quoted for 'truth'.
=====================
If your MkIII has an air shock, make sure it isn't regularly bottoming out. They were very well liked, and were one of the first "DW" link frames on the market that are all the rage today. 
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For the record, chains don't really 'stretch' so much as they 'wear' in the pins and bushings. However, the net effect is pretty much the same as if it did stretch.
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If you don't ride in a wet/damp environment, I wouldn't worry about using full length cable housing. It will actually produce more friction than a correctly installed cable with interrupted sections of housing.

And it is true that the rear most section of housing is usually the one that gets worn the soonest, likely due to the tight bend/loop it makes as it connects to the derailleur. Many times, you can just replace that one section of housing and be good to go for a while, but if you have the resources, it is good to replace all of the housings and the cable to be sure it isn't going to be an issue.
=====================
Following the Park Tool instructions to make repairs to your bike is good advice. The sooner you learn to do it yourself, the sooner you start saving $$$ on repairs and maintenance.

If you're going to have a shop do it, I would consider asking them about the different tune-up packages they offer. Sometimes, they will install cables and housings (and other parts) when they are getting replaced while getting a tuneup, and they'll go through the rest of the bike while they are at it. Maybe even take the drivetrain off of the bike and put it through the parts washer. Saves the cost of paying separate labor charges to have new parts installed, giving you more value for the dollars you spend.


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## idividebyzero (Sep 25, 2014)

So I replaced the chain, the middle chainring(crank), and wire. Now Im getting really bad chain slip to the point its unridable uphill on most gears.

If I pedal very slowly with the bike in a stand and change gear then sometimes the chain wants to ride on top of the teeth for a bit.

Do I need a new cassette too? Did I install the chain wrong? Derailleur settings messed up? I have a 9speed cassette and got a 9 speed chain.


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## kapusta (Jan 17, 2004)

idividebyzero said:


> So I replaced the chain, the middle chainring(crank), and wire. Now Im getting really bad chain slip to the point its unridable uphill on most gears.
> 
> If I pedal very slowly with the bike in a stand and change gear then sometimes the chain wants to ride on top of the teeth for a bit.
> 
> ...


Did you change the cable housing along with the cables?

If the chain was really worn then the cassette likely was as well. New chain with worn cassette often do not play nice together.

We can't diagnose the rear deraileur adjustment over the internet. Assuming you have new cable and housing go to the park tool website for tips on how to set ip the RD.


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## J.B. Weld (Aug 13, 2012)

kapusta said:


> Did you change the cable housing along with the cables?


I was going to ask the same thing, it's no good changing the cables without doing the housing too.

The skipping issue is almost for sure the cassette, very common after replacing a very worn chain without replacing the cassette.


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## Mr Pig (Jun 25, 2008)

idividebyzero said:


> So I replaced the chain, the middle chainring(crank), and wire. Now Im getting really bad chain slip to the point its unridable uphill on most gears.
> 
> If I pedal very slowly with the bike in a stand and change gear then sometimes the chain wants to ride on top of the teeth for a bit.
> 
> Do I need a new cassette too? Did I install the chain wrong? Derailleur settings messed up? I have a 9speed cassette and got a 9 speed chain.


Do people listen to anything I say? ;0)

Yes, you need to replace the whole transmission. All of the front rings, chain and cassette. Nothing else will work.

To avoid this happening in future you can replace the chain when it gets to around 1.7% worn. Leave it much beyond that and you'll be back here again in a few years.

Or just ride the bike until it's all worn out again. Either way is viable.


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## J.B. Weld (Aug 13, 2012)

Mr Pig said:


> Yes, you need to replace the whole transmission. All of the front rings, chain and cassette. Nothing else will work.


The OP did replace the middle one which is generally the most used, I'd say there's a good chance he/she will be fine with just the cassette. I've replaced many hashed out chains & cassettes without replacing any front rings with good results.


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## Mr Pig (Jun 25, 2008)

J.B. Weld said:


> The OP did replace the middle one which is generally the most used


True, but it's usually the small one that wears quickest. It might not get used as much but it tends to get more pressure put on it and it has less teeth to bear it.

Although you can often just flip the small ring over as it's just a flat disk? I wish they would make the other chain rings so that you can flip them over when they wear. Can't imagine why they wouldn't do that...


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## Guest (Oct 4, 2014)

Mr Pig said:


> True, but it's usually the small one that wears quickest. It might not get used as much but it tends to get more pressure put on it and it has less teeth to bear it.
> 
> Although you can often just flip the small ring over as it's just a flat disk? I wish they would make the other chain rings so that you can flip them over when they wear. Can't imagine why they wouldn't do that...


 Don't like to generalize, but I think people are often "Snake-charmed" by inconsequential gains in performance. The whole pinning and ramping of larger chainrings makes them poor candidates for flipping, although the real reason is probably market driven.


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## StiHacka (Feb 2, 2012)

Reading the OP, I see classic symptoms of poorly set B-screw. How far are the RD jockey wheels from the cassette? If too close, shifting will be "clunky". If too far, chain will hesitate to make the shift.


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## idividebyzero (Sep 25, 2014)

An update:

I purchased an XT cassette (reviews mentioned that it shifts smoother than standard deore/alivio). I also got new shift housing installed.

The cassette did nothing for smoother shifting but it solved the chain slip. The housing improved shifting to a larger gear (it was sloppy before, requiring 2 up 1 down) but not shifting to a smaller gear, shifting to a smaller gear is when I get the clunk.

I tried messing around with the B screw but I cant notice it doing anything, its not a Shadow derailleur, just a plain Deore. Even with the screw all the way out the wheel doesnt come anywhere near 2mm from the largest cog (which is what seems to be recommended, but those were for shadow style), its more like 3/4".

Do 9 speeds just suck at shifting to a smaller cog because the changes are larger? I havent found any videos of a 9 speed shifting properly, but its certainly nowhere near as smooth as all the 10 speeds Ive seen.


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## eb1888 (Jan 27, 2012)

Well things are looking up.
Did you also replace the ferrules and cable? And add a couple drops of silicone lube or spray.
I have a extra 9sp bike with SLX shifters and a Deore rear derailleur that is shadow. With the REI Novara/Jagwire kit run full length through drilled out stops it shifts like butter perfectly in every gear. That smallest gear requires the least amount of cable tension so cable drag affects things there.
So shift down to that gear and check for slack. Also make sure the stop screw is correctly adjusted. Loosen the cable stop bolt and remove any after setting the barrel adjusters in mid- tight positions.


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## Mr Pig (Jun 25, 2008)

idividebyzero said:


> The cassette did nothing for smoother shifting but it solved the chain slip.


Sounds like your cassette was worn. I find that how worn componants are makes a much bigger difference than what type/series they are. I buy lower-end cassettes now because, apart from the weight penalty, they do the same thing.



> Do 9 speeds just suck at shifting to a smaller cog because the changes are larger?


Not really. They are a little more footery to set up, because the chain and dérailleur cages are narrower, but when set up right they should work fine.


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