Rear derailleur shifting weirdly ?

R.dufy454773

I’ve recently noticed that when shifting up to easier / larger Cogs at the rear cassette when I shift up one gear, it shifts up to gears and then drops down one gear to the gear I want . (It’s a fairly new bike so chain/ cables couldn’t be worn )


Anyone know how to fix this ? Thanks

rollingscone

R.dufy454773 wrote: »

I’ve recently noticed that when shifting up to easier / larger Cogs at the rear cassette when I shift up one gear, it shifts up to gears and then drops down one gear to the gear I want . (It’s a fairly new bike so chain/ cables couldn’t be worn )


Anyone know how to fix this ? Thanks

Have you taken the wheel off recently?

If not, is the casette loose?

R.dufy454773

rollingscone wrote: »

Have you taken the wheel off recently?

If not, is the casette loose?

Hi, yes I have taken the wheel off recent and I think it was just skipping gears before but not sure because I didn’t try to fix it . And i don’t think the cassette is loose

07Lapierre

R.dufy454773 wrote: »

I’ve recently noticed that when shifting up to easier / larger Cogs at the rear cassette when I shift up one gear, it shifts up to gears and then drops down one gear to the gear I want . (It’s a fairly new bike so chain/ cables couldn’t be worn )


Anyone know how to fix this ? Thanks

They could be. How old is the bike exactly?

mp31

Sounds like the rear derailleur may need adjustment via the barrel adjuster.

Note that a small movement on the shifter will move the chain across one sprocket, a larger movement on the shifter will move the chain across two sprockets

R.dufy454773

07Lapierre wrote: »

They could be. How old is the bike exactly?

I bought it in November and have only done about 500-600km snd they don’t feel/ look worn

R.dufy454773

mp31 wrote: »

Sounds like the rear derailleur may need adjustment via the barrel adjuster.

Note that a small movement on the shifter will move the chain across one sprocket, a larger movement on the shifter will move the chain across two sprockets

Yeah I know but I only move it slightly and it moves up two then goes back one to where I want it

R.dufy454773

mp31 wrote: »

Sounds like the rear derailleur may need adjustment via the barrel adjuster.

Note that a small movement on the shifter will move the chain across one sprocket, a larger movement on the shifter will move the chain across two sprockets

Yeah I know but I only move it slightly and it moves up two then goes back one to where I want it

CrowdedHouse

Did the bike fall over or get a bump on the drive side? my one behaved kinda like that when I bent the hanger.

The Ging and I

Your drop out might be out of alignment and this is the biggest cause of rear mech problems. Bring it to a shop which has the tool to check this.

R.dufy454773

I don't think it's bent? The jockey wheels are directly under the chain ?🤔

What Username Guidelines

Could be new cables stretching and the rear derailleur just needs some adjusting

07Lapierre

R.dufy454773 wrote: »

I bought it in November and have only done about 500-600km snd they don’t feel/ look worn

500-600k? ...yep cables have stretched.

R.dufy454773

07Lapierre wrote: »

500-600k? ...yep cables have stretched.

Yeah I know they stretch but they don't need to be replaced do they ?


Btw* I just checked and I have only done about 396km but I still think they have stretched but not needing to be replaced

07Lapierre

R.dufy454773 wrote: »

Yeah I know they stretch but they don't need to be replaced do they ?

No, but the rear derailleur cable may need to be tightened.


https://youtu.be/Bbk5RcH0bbQ

What Username Guidelines

R.dufy454773 wrote: »

Yeah I know they stretch but they don't need to be replaced do they ?


Btw* I just checked and I have only done about 396km but I still think they have stretched but not needing to be replaced

No, no need to replace, they generally just stretch from usage when new and once adjusted it should be fine.

R.dufy454773

What Username Guidelines wrote: »

No, no need to replace, they generally just stretch from usage when new and once adjusted it should be fine.

Yeah that's what I thought

martyc5674

A stretched cable on your rear derailleur would manifest as a reluctance to go into the lower gears(larger sprockets)... your experiencing the opposite where it is actually pushing the derailleur towards the lower gears. Something else is causing this.
Marty.

R.dufy454773

martyc5674 wrote: »

A stretched cable on your rear derailleur would manifest as a reluctance to go into the lower gears(larger sprockets)... your experiencing the opposite where it is actually pushing the derailleur towards the lower gears. Something else is causing this.
Marty.

Hi Marty,


When I try to shift in to a lower/easier gear the derailur shifts up 2 cogs instead of one , so it is reluctant to go into lower gears. I think you think the opposite but correct me if I’m wrong .

I’ll look at tightening the cable in the morning

martyc5674

R.dufy454773 wrote: »

Hi Marty,


When I try to shift in to a lower/easier gear the derailur shifts up 2 cogs instead of one , so it is reluctant to go into lower gears. I think you think the opposite but correct me if I’m wrong .

I’ll look at tightening the cable in the morning

No I reckon I understood you correctly.
If it’s shifting 2 sprockets instead of one when down shifting (albeit momentarily and returning to actually only shift 1 position)... then a stretched cable is not the issue.
A stretched cable would manifest as a reluctance to go down gears.. yours is almost going down 2.
Marty.

R.dufy454773

martyc5674 wrote: »

No I reckon I understood you correctly.
If it’s shifting 2 sprockets instead of one when down shifting (albeit momentarily and returning to actually only shift 1 position)... then a stretched cable is not the issue.
A stretched cable would manifest as a reluctance to go down gears.. yours is almost going down 2.
Marty.

Yes that’s it but it’s when I’m shifting up gears in to bigger tooth cogs I’d thats what you mean?

martyc5674

R.dufy454773 wrote: »

Yes that’s it but it’s when I’m shifting up gears in to bigger tooth cogs I’d thats what you mean?

Yeah that’s what I mean... the bigger gears at the back are the lower gears. (Smallest being highest)

Just to be clear... the quote above ”shifting up gears to bigger cogs” is incorrect.
It should be shifting down gears to bigger cogs.... bigger = lower.

R.dufy454773

martyc5674 wrote: »

Yeah that’s what I mean... the bigger gears at the back are the lower gears. (Smallest being highest)

Just to be clear... the quote above ”shifting up gears to bigger cogs” is incorrect.
It should be shifting down gears to bigger cogs.... bigger = lower.

Yes exactly thanks for saving me doing that , do you know anything I could try to fix it ?

martyc5674

You could try turning the barrel adjuster clockwise a quarter turn at a time to take some of the tension out of the cable.


Before you do that though make sure your back wheel is sitting home in the dropout.

Loosen skewer(pull lever back)... push down on saddle keeping s little pressure and retighten skewer.

As others have said it’s normal for cables to stretch but yours seems to have somehow shrunk so I reckon something else might have happened.
Marty.

R.dufy454773

martyc5674 wrote: »

You could try turning the barrel adjuster clockwise a quarter turn at a time to take some of the tension out of the cable.


Before you do that though make sure your back wheel is sitting home in the dropout.

Loosen skewer(pull lever back)... push down on saddle keeping s little pressure and retighten skewer.

As others have said it’s normal for cables to stretch but yours seems to have somehow shrunk so I reckon something else might have happened.
Marty.

I was messing about with the barrel adjuster for some other problem a few months ago whichu for get which it was but anyway I went to turn the barrel adjuster and it was really tight and super difficult to move

Then i said I’d try tighten the rear derailleur cable and I unscrewed the bolt out all the way by accident and then during this the gears went from the third hardest gear straight down to the smallest / hardest cog and then the derailleur cable popped out .

So I went to put it back in but I couldn’t pull it as tight as it was before . I then tried shifting and it makes a horrible clicking sound and it takes two clicks to go up 1 cog and it won’t go up any more

So now basically I’m stuck with only 2 gears that makes a clicking sound

I just couldn’t pull the cable as tight as it was before

07Lapierre

R.dufy454773 wrote: »

I was messing about with the barrel adjuster for some other problem a few months ago whichu for get which it was but anyway I went to turn the barrel adjuster and it was really tight and super difficult to move

Then i said I’d try tighten the rear derailleur cable and I unscrewed the bolt out all the way by accident and then during this the gears went from the third hardest gear straight down to the smallest / hardest cog and then the derailleur cable popped out .

So I went to put it back in but I couldn’t pull it as tight as it was before . I then tried shifting and it makes a horrible clicking sound and it takes two clicks to go up 1 cog and it won’t go up any more

So now basically I’m stuck with only 2 gears that makes a clicking sound

I just couldn’t pull the cable as tight as it was before

Remove the cable again. Then unscrew the barrel adjuster and remove it completely. Clean it with WD40... clean it with a cloth, clean the treads on the rear derailleur as well. Then put the barrel adjuster back but only thread it 1/2 way into the derailleur. Recommect the cable and then use the barrel adjuster to adjust the cable tension (that’s what it’s for)

R.dufy454773

07Lapierre wrote: »

Remove the cable again. Then unscrew the barrel adjuster and remove it completely. Clean it with WD40... clean it with a cloth, clean the treads on the rear derailleur as well. Then put the barrel adjuster back but only thread it 1/2 way into the derailleur. Recommect the cable and then use the barrel adjuster to adjust the cable tension (that’s what it’s for)

Remove just the plastic housing or the entire thing of the barrel adjuster thanks

07Lapierre

R.dufy454773 wrote: »

Remove just the plastic housing or the entire thing of the barrel adjuster thanks

the whole thing.

should look like this:

https://images-na.ssl-images-amazon.com/images/I/51G9hoT7X0L._SL1081_.jpg

R.dufy454773

07Lapierre wrote: »

the whole thing.

should look like this:

https://images-na.ssl-images-amazon.com/images/I/51G9hoT7X0L._SL1081_.jpg

Yes it’s like that thabks a lot



Edit : I am turning it away from the bike but the outer plastic housing won’t stray over the barrel adjuster it just springs out

07Lapierre

R.dufy454773 wrote: »

Yes it’s like that thabks alot

Watch this:

https://www.youtube.com/watch?v=Bbk5RcH0bbQ

R.dufy454773

07Lapierre wrote: »

Watch this:

https://www.youtube.com/watch?v=Bbk5RcH0bbQ[/quote

I think I’ve got the barrel adjuster sorted but the cable is still not as tight as before so that’s normal ?