Triple dropping straight to small ring?

[Tommy2]

Shimano sora 9spd triple, goes up on the front 3 ring fine but when dropping down from the big ring it goes straight to.the small ring as if there is only 1 click,.like a double?
Any thoughts?
I've tried adjusting the lower and upper limits and the derailleur inertia plate is only 1mm away from the chain when on the small ring.

 

[alecstilleyedye]

i've got the same problem. suspected it was to do with worn chainrings, but has persisted even since those were replaced. hoping it's not the shifter (tiagra 9-speed)…

 

[raleighnut]

It's the cable tension that needs adjusting (tightening)
On a triple the high stop controls positioning on the big ring and the low stop controls the inner whereas the middle ring position is only controlled by the cable tension.

 

[Tommy2]

It seems to have done it since they were new and they've not got loads of miles on them now, thinking it may be the shifter as when I flip the small lever to drop down and keep it held it goes down to the middle ring but when I let go of the lever just a little it drops the derailuer and extra click.
Something must be snapped of worn inside.

 

[Tommy2]

@raleighnut I just saw your message after I'd posted again, I've tried setting the lower stop then taking the slack out of the cable when it's on the small ring, is that right?

Or should I lower the low stop and tension the cable to adjust the derailuer in to rest position on the small ring?

 

[Ian H]

As Raleighnut says, it's not the limit adjusters, it's the cable tension. Tighten it until the chain drops correctly on to the middle ring, then check everything else.

 

[raleighnut]

@raleighnut I just saw your message after I'd posted again, I've tried setting the lower stop then taking the slack out of the cable when it's on the small ring, is that right?

Or should I lower the low stop and tension the cable to adjust the derailuer in to rest position on the small ring?

No you should adjust the tension so that when the middle ring is selected the front derailleur is centred on the middle ring, you should then be able to select gears 2-8 at the rear (on a 9 speed) with no chain rub at the front.

 

[User6179]

It is a lot easier to set up a triple set up correctly with an inline adjuster in place

 

[lpretro1]

It is a lot easier to set up a triple set up correctly with an inline adjuster in place

Unless u already have down tube adjusters in place of course

 

[Racing roadkill]

I had a bugger of a job getting my Sora 9 speed triple to behave itself for the first month or so that I had it. It just seems to be very critical to periodically set the front to the smallest ring, and the rear to the smallest sprocket, then release the pinch bolt on the front mech cable, pull the cable tight, then retighten the pinch bolt, until the cable settles in, regarding initial stretching due to shifting when the cable is new. It's been the same story when I've replaced the cables as well.

 

[Ajax Bay]

regarding initial stretching due to shifting when the cable is new

As has been discussed before, stainless steel cables do not stretch anymore than normal when new ie they stretch the same amount every time (the same amount of) tension is applied, throughout their life, from brand new to 'ready for replacement'.

 

[MichaelW2]

Also check the alignment/rotation of the front mech.

 

[mythste]

As has been discussed before, stainless steel cables do not stretch anymore than normal when new ie they stretch the same amount every time (the same amount of) tension is applied, throughout their life, from brand new to 'ready for replacement'.

What has been discussed is that stainless steel cables do not stretch at all. The cable outers, however, may groove.

The linearity of that appears to be up for debate.

 

[Plumster]

Shimano sora 9spd triple, goes up on the front 3 ring fine but when dropping down from the big ring it goes straight to.the small ring as if there is only 1 click,.like a double?
Any thoughts?
I've tried adjusting the lower and upper limits and the derailleur inertia plate is only 1mm away from the chain when on the small ring.

I came across similar problem yesterday when setting up the gears on a mountain bike, instead of taking up the cable slack whilst on the smallest ring, I had to slacken the cable so that it would select the middle ring, if the limit screws are set correctly it will still drop ok to the smallest ring when required

 

[raleighnut]

I came across similar problem yesterday when setting up the gears on a mountain bike, instead of taking up the cable slack whilst on the smallest ring, I had to slacken the cable so that it would select the middle ring, if the limit screws are set correctly it will still drop ok to the smallest ring when required

It is quite usual on some set ups to have slack in the cable when in the small ring on a triple, as long as the 'low' stop is set correctly it isn't a problem.