loose chain only on granny gear?

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botch

Likes Bikes
Hey all

so i got a bike stand for chrissy so i can start doing more myself and learn more about my bike too. I do the basic stuff, but am now a the point of being able to regrease suspension linkage points, bottom bracket etc.

So anyway, put the bike in the stand this morning, and noticed that when it was in the easy gear front and rear, the chain was really loose. I've never noticed this before as i normally have the bike flipped upside down. Any other gear is good, even having large chainring front and large cog rear.

Surely this wouldnt be a loose chain? Is there something else that could cause this?

Cheers
 
B

botch

Likes Bikes
Is there an easy way to determine it?

The cage is an x9 medium cage (2x9) which is the original cage, and the chain is still the original chain aswell.
I would imagine it should suit properly given these are the bits that came with the bike?
 
moorey

moorey

call me Mia
botch said:
Is there an easy way to determine it?

The cage is an x9 medium cage (2x9) which is the original cage, and the chain is still the original chain aswell.
I would imagine it should suit properly given these are the bits that came with the bike?
Click to expand...
Put it in big and big, if it's fairly tight like that, but still loose in small small, you'll need a longer cage mech.
 
pharmaboy

pharmaboy

Eats Squid
botch said:
Is there an easy way to determine it?

The cage is an x9 medium cage (2x9) which is the original cage, and the chain is still the original chain aswell.
I would imagine it should suit properly given these are the bits that came with the bike?
Click to expand...
What do you mean loose? The gears for testing chain length etc are small front small rear and big front big rear as these are the 2 extremes .

image.jpg

That's big big and about what it should look like
 
Minlak

Minlak

custom titis
Don't forget to allow for chain growth if you have a dual suspension bike. Depending on the suspension the chain can need to be longer at full travel.
 
pink poodle

pink poodle

気が狂っている男
I know a bike shop that fits them like that, so must be fine...

What are the big teeth and little teeth counts? Your big ring on the back looks massive! I would try and fit a bigger granny on the crank or a smaller range cassette on the back. But you should go single up front and solve the issue entirely.
 
A

Alex Dlugosch

Likes Dirt
By the way OP, that isn't "easy gear front and rear". Its actually "small small".

The easy gear front and rear is small front ring and big rear cog.

You shouldn't ever use small small because it has a terrible chain line, and more importantly, the chain tension in that combination is extremely high and it will wear your drivetrain really quickly. That's why its sometimes okay to have a loose chain in that combo, because you should never shift into it.
 
B

botch

Likes Bikes
Yeah i realised after i submitted it that i wrote it wrong!

I dont generally use granny up front unless i'm at the end of a ride and knackered!
 
A

Alex Dlugosch

Likes Dirt
All good, I kinda knew what you meant! Then I saw the photo and yeah.

Using the granny is fine, just don't use it in the smallest 2 or 3 cogs.
 
pharmaboy

pharmaboy

Eats Squid
Mate, there's something wrong with that deraileur .

It is either not mounted correctly on the lug from the hanger, or it is something like a broken spring. When there is no tension on a deraileur it should be very compact with the bottom jockey wheel equal with or higher than the top jockey wheel
 
B

botch

Likes Bikes
Just got home from some more family eating time. Had another look....seems that gears 8 and 9 are the only two affected when on the small front ring. I can push the derailleur up to where it should be and the chain tightens to where it should.

I've had a look at the rear mech...all the bolts look tight, the one spring i can see looks ok. Is there an internal spring somewhere that may be knackered? Not really wanting to buy a new derailleur if there is something else causing the issue.

Cheers
 
beejay

beejay

Likes Dirt
teK-- said:
Chain too long and/or derailleur cage too short.
Click to expand...
Second that.

Your derailleur looks like it's working fine. It looks pulled back tight in the granny ring combo so I don't think it's the spring tension. Do you know which cage length it is? (e.g. short, medium or long?).
Does the suspension drop when in the stand? enough maybe to shorten up the chainstay so the chain loosens?

More questions than answers I know but I think tek is correct.
 
MARKL

MARKL

Eats Squid
Start simple, I would adjust the 'b' screw first and take it from there (easy to find videos on the net I just can't get a link to work) also make sure your b screw is pressing against the derailleur hanger properly.
 
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pharmaboy

pharmaboy

Eats Squid
beejay said:
Second that.

Your derailleur looks like it's working fine. It looks pulled back tight in the granny ring combo so I don't think it's the spring tension. Do you know which cage length it is? (e.g. short, medium or long?).
Does the suspension drop when in the stand? enough maybe to shorten up the chainstay so the chain loosens?

More questions than answers I know but I think tek is correct.
Click to expand...
An x9 should look like this ,

image.jpg

Under no tension, but MARKL has a point, if the b tension screw is wound all the way out, it might create a strange angle like that, but OTOH sram deraileurs are known for losing tension in the bottom couple of cogs.

Botch has already said it's medium cage not short , if he's got 42 and 24 on it, then all bets are off, but if it's 2x rings it shouldn't do that. Check b limit screw as suggested first, make sure your front isn't different by more than 14 teeth as well.
 
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