Rear derailleur woes

penexpers

I'm rapidly remembering why I like internal gear hubs better.

Anyway I have a rear derailleur that I am trying to get working with the Shimano bar end shifters. I have the cable nice and tight and it's able to through the gears (from smallest to largest cog) no problem. However when I try to go back down through the gears, the derailleur doesn't pick up the slack in the cable and the cable gets pushed back out through the shifter. I've tried adjusting the barrel adjusters to take up the slack but that doesn't work. Does anyone have an ideas what I could be doing wrong? Thanks.

kona

penexpers wrote: »

I'm rapidly remembering why I like internal gear hubs better.

Anyway I have a rear derailleur that I am trying to get working with the Shimano bar end shifters. I have the cable nice and tight and it's able to through the gears (from smallest to largest cog) no problem. However when I try to go back down through the gears, the derailleur doesn't pick up the slack in the cable and the cable gets pushed back out through the shifter. I've tried adjusting the barrel adjusters to take up the slack but that doesn't work. Does anyone have an ideas what I could be doing wrong? Thanks.

Have you made sure either the derailler or the shifter, isnt one one those stupid shimano push derailleurs(cant remember the exact name but they work opposite to normal)

Limits.

Are they new cables, both inner and outer?

irishmotorist

I'm not sure that I totally understand, but if the derailleur isn't falling back down from big to small sprockets, two things spring to mind:

1. The derailleur is in need of a bit of oil and TLC. If you press it in manually with your hand, does it come back out when you remove pressure?
2. Are there any angles along the cable route that might be causing the cable to be caught/snagged when you change down a gear and thus not releasing the tautness?

penexpers

kona wrote: »

Have you made sure either the derailler or the shifter, isnt one one those stupid shimano push derailleurs(cant remember the exact name but they work opposite to normal)

Limits.

Are they new cables, both inner and outer?

Limits are fine. New cables, tried multiple cables too.

I think I understand your first point. I don't think there's a problem in compatibility between the shifter and the derailleur.

penexpers

irishmotorist wrote: »

I'm not sure that I totally understand, but if the derailleur isn't falling back down from big to small sprockets, two things spring to mind:

1. The derailleur is in need of a bit of oil and TLC. If you press it in manually with your hand, does it come back out when you remove pressure?
2. Are there any angles along the cable route that might be causing the cable to be caught/snagged when you change down a gear and thus not releasing the tautness?

1. Derailleur is brand new out of the box. When I loosen the cable it springs back down to the lowest sprocket. I should mention that the tension between the adjustment bolt and the derailleur is still tight, the rest of the cable isn't.

2. No it's all perfectly normal.

kona

penexpers wrote: »

Limits are fine. New cables, tried multiple cables too.

I think I understand your first point. I don't think there's a problem in compatibility between the shifter and the derailleur.

Is the shifter "clicking" as you shift down? The is a spring that pushes the shifter around and so takes up the slack.

Id be looking at the cable routing and shifter.

Here is a test, Take off the cable and shifter, pull the cable tight and make the shifter shift, you should feel the cable pulling and releasing.

penexpers

kona wrote: »

Is the shifter "clicking" as you shift down? The is a spring that pushes the shifter around and so takes up the slack.

Id be looking at the cable routing and shifter.

Here is a test, Take off the cable and shifter, pull the cable tight and make the shifter shift, you should feel the cable pulling and releasing.

These shifters don't have springs and are friction shifters. In any case I think you're confused. When you are shifting down (from largest to smallest at the rear), then you are releasing tension from the shifter and the derailluer should pick up the slack (the spring in the derailleur should pick up the slack, not the shifter).

kona

penexpers wrote: »

These shifters don't have springs and are friction shifters. In any case I think you're confused. When you are shifting down (from largest to smallest at the rear), then you are releasing tension from the shifter and the derailluer should pick up the slack (the spring in the derailleur should pick up the slack, not the shifter).

Get ya.

So the derailleur is the issue. As Irishmotorist said, can you pull it down by hand?

How tight is the loop on the outer cable from the frame into the barrel adjuster on the derailleur?, is it sitting into the barrel adjuster correctley? are yu using ferrules?

penexpers

Found the problem. The frame is interfering with the derailleur. Anyone want a barely used Deore derailleur for 20 quid?

kona

penexpers wrote: »

Found the problem. The frame is interfering with the derailleur. Anyone want a barely used Deore derailleur for 20 quid?

Is the frame ment to take a derailleur, seems odd?

penexpers

kona wrote: »

Is the frame ment to take a derailleur, seems odd?

No it is, just not long cage ones. Looks like short and mid cage fit ok. I had a 105 on it last and that was fine.

kona

penexpers wrote: »

No it is, just not long cage ones. Looks like short and mid cage fit ok. I had a 105 on it last and that was fine.

That sucks:(