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Discussion Starter · #1 ·
I'm a little confused with a problem I noticed. I was out for a ride and in certain gears I noticed chatter. I expected this at some point because I put a new derailleur + new cable on at the same time, and I knew at some point I'd have to make adjustments for the chain stretch.

Whenever I got the setting right, I'd shift to each gear and there was always a problem somewhere else on the cassette.

I decided, instead of going by ear, I'd take a close look at how the chain sits on the cogs. I adjusted the derailleur in my normal way in one of the center cogs and took notice to how it was sitting. Then I adjusted to the larger gears and noticed that the spacing seemed off. Like there seemed to be no consistency in the space between the chain and the next cog. Sometimes there were large gaps, other times there was direct rubbing with the next cog.

My cassette and chain were new as of a month ago, and the chainrings were new as of April or so. Everything has been running flawlessly, and the cable seems to have no issues with the housing. Like I said, once it happened I was like, oh okay, chain stretch - readjust. But now it just seems weird.

I'm done with tinkering with it tonight, but I figured I'd post here just in case someone else can relate or throw something my way. If not, I'll tackle it tomorrow when I have a little more energy. :)
 

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Chain stretch should not be an issue as it takes many, many miles to stretch a chain. Cable stretch could be an issue, but it sounds like you know how to use the barrel adjusters to set your indexing. It sounds like its probably a bent derailleur hanger. Look at your bottom cogs on the rear derailleur. If it is not completely vertical, the hanger is probably bent. This could lead to some gears working and losing other gears as you move up or down the rear cassette.
 

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As ooctrl noted...

most likely a bent derailleur hanger. You can take a look at it and possibley see it. However, it doesn't take much misalignment of the hanger to cause problems. As little as 2 or 3mm off can cause the problem you describe. There are tools for aligning derailleur hangers. The most common is the Park Tool DAG-1. Any competent LBS should have one, and they'd likely charge around $10 to do the job. I'd have it checked at a shop, or borrow the tool if you know anyone that has one. Der hangers can be bent a bit by seemingly minor things, banging around a bit on a bike rack, a tip over to the drive side, a crash, etc.

Anyway have it checked and/or aligned. Hanger alignment is quite likely your problem.
If it's not the hanger come on back and let us know. There could be other issues, but they are much less common/likely, but still possible.

Good Dirt
 

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Discussion Starter · #5 ·
I didn't think about the der hanger at all, mostly because... I haven't wrecked a single time since the last time I had it checked.

However, if I cannot get anything figured out with tonight as far as adjustments go, I'll swing in to the bike shop to see if that's it. Thanks guys!
 

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Another thing to check is to make sure the cable is installed on the derailleur correctly. Usually there is a small slot under the bolt that clamps the cable down. Make sure the cable is in that slot. If it's not (like cable installed on wrong side of the bolt) this will cause shifting to get worse as you go up the cassette.
 

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ooctrl said:
Look at your bottom cogs on the rear derailleur. If it is not completely vertical, the hanger is probably bent. This could lead to some gears working and losing other gears as you move up or down the rear cassette.
Can anyone confirm this? When I look at my alignment of derailleur to cog, it seems angled in towards the middle of the casette to a degree on both larger and smaller cogs, but is ligned up vertically on the very center cogs. My hanger can't be bent both ways LOL
 

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Discussion Starter · #8 ·
Noclutch said:
Can anyone confirm this? When I look at my alignment of derailleur to cog, it seems angled in towards the middle of the casette to a degree on both larger and smaller cogs, but is ligned up vertically on the very center cogs. My hanger can't be bent both ways LOL
To be honest, it's hard to visually determine if your hanger is bent. Surely if you look at it and its on a 90 degree angle, duh, there's a problem.

But cog teeth tend to sometimes look different from one to another, and sometimes have a slight angle to them. Adding to it, if you look at your frame while you're trying to determine if your hanger is bent, you'll also be thrown off since the rear triangle to all bikes is never dead center straight box-style, it's always angled as the tubes come back upward toward the seat post.

In other words, I have had a few bent hangers that I visually could not tell, but when I put a hanger checker on it, it was obvious. However, I didn't even take that into consideration this time, mostly because when I have a wipe out, that's when my brain is activated to be aware of shifting issues. But since I had my hanger checked last, I haven't had a single wreck, which is why when this issue came up my instinct was cable stretch - due to the new cable I installed.

Everything is installed correctly and it's mounted at the rear derailleur as it should be and tightened down accordingly. Like I said, once it happened, blam - chain stretch. Ahh, not so much... :p

Thanks again guys.
 

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Discussion Starter · #9 · (Edited)
Just came back from the bike shop - they said the hanger was perfectly straight and made no adjustments to it, and as such, didn't charge me a dime.

I came home and put my bike on my stand and began to notice a pattern.

I have a low-normal derailleur, or whatever it is where its "idle" position is on the largest cog, whereas regular derailleur's sit idle (without cable installed) at the smallest position.

When I push in with my thumb, which bumps to the next smallest cog, I saw a pattern... if I just kinda "press" it and it clicks, that's not good enough. I need to have a profound BAM - swift click into position. If I do that, each time its perfect. If I just kinda push it and it clicks and whatever, it sounds like it's a little out of whack.

Think my shifter itself needs some TLC, or perhaps a replacement?

EDIT - I took the chain off and thoroughly cleaned it with a degreaser. I also cleaned up the cassette and checked out the derailleur. It seemed to freely flow from outer to inner rings with ease, but despite this, I put a few drops of lube at the pivot joints of the derailleur. This seemed to do nothing, as it was already moving flawlessly with no hesitation or odd feeling. I also gripped the cable lightly, which was detached from the derailleur. I began shifting through the gears, and the cable seemed to show no signs of hesitation at all. I'm not too sure what this means, but I'm really beginning to think it's the shifter up front. The reason for this is quite simple. If I am looking down at my rear derailleur and I press with my thumb until it clicks, I take note of how far it visually travels. If I go back to the previous gear to repeat the EXACT same steps I did before, but then press it firmly to go to next gear (profoundly as I explained above) it seems to move a bit further.

If I press with my thumb just until it clicks, sometimes it doesn't shift, and it visibly does not travel as far.

If I press with my thumb firmly to make the click happen, it always shifts, and it visibly travels a bit further.

Thoughts?
 

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Discussion Starter · #10 ·
I did some more reading tonight, as well as talked to a few bike mechanic friends of mine. The shifters were stock on my hardtail, which began as a 400 dollar hardtail that I've upgraded almost everything on. The shifters are one of the few things that remain stock on it.

Based on what I read, some users indicated that lower quality shifters can wear out and indeed mess up the indexing. Based on what I saw tonight and the fact the hanger and everything else was checked, I ended up getting a pair of 9spd shifters on JensonUSA (Shimano LX M580's) on closeout sale for 45 bucks.

We'll see if they fix it. Quite honestly, everything else is new, so I'm confident this is the issue. I'll report back regardless in case anybody is curious and for learning purposes of other readers.
 

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Roasted said:
Based on what I read, some users indicated that lower quality shifters can wear out and indeed mess up the indexing. Based on what I saw tonight and the fact the hanger and everything else was checked, I ended up getting a pair of 9spd shifters on JensonUSA (Shimano LX M580's) on closeout sale for 45 bucks.
I had a set of Deore shifters that I put several thousand miles on in all conditions. It got to the point where they would work fine, as long as I clicked the shifter twice per one gear. It was weird and kind of annoying.

Point being: Shifters do wear out, though much slower than cassettes and chains. Cheaper ones wear quicker (and don't perform as well when they're new). Hopefully the new units solve your problem.
 

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I must admit up front that I didn't read the thread at all......barely skimmed through it.

How old are your cables?

Low normal setups are sometimes very sensetive to gummed up cables.

If its been more than a year since you changed them, get new cables and housing now.

A quick troubleshoot would be to drip some tri flow into the cable ends and let gravity run the oil through the cables.
 

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Discussion Starter · #13 ·
savagemann said:
I must admit up front that I didn't read the thread at all......barely skimmed through it.

How old are your cables?

Low normal setups are sometimes very sensetive to gummed up cables.

If its been more than a year since you changed them, get new cables and housing now.

A quick troubleshoot would be to drip some tri flow into the cable ends and let gravity run the oil through the cables.
Reading the thread would have answered all of these questions...

- The cable is very new. It's only about 4 weeks old.
- I placed a drop of oil in the housing, not to mention the housing itself isn't that old either.
- I disconnected the cable from the RD and moved it through the housing from each end, and it moved seemlessly. No lag or jerkiness.
- When I physically watch the derailleur, if I do not press the shifter firmly, it physically does not move as far as it does when I press the shifter firmly. I can see there is a difference in the RD's travel based on my movement with the shifter. However, the shifter is "clicking" into place in both scenarios.

When this problem started, I expected it to be cable stretch since it's been a few weeks. But once I dialed in the RD, I noticed the problem didn't go away, and shortly after realized the inconsistencies from the shifter...
 
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