sora sti 8 speed jamming

[stephenjubb]

Occasionally my front left sora sti (controlling my front derailleur) jams completely and refuses to move sideways, though it still brakes. after a few minutes it somehow releases itself.

Has anyone experienced this, any opinions, is it a design issue and will it be permament?

I am off on tour for 2 months to scotland and do not want it to go then

 

[stoatsngroats]

I have Sora, bought used, and I've had no problems as yet!

Just a thought - you say refuses to move sideways....can you release the button when this happens?

 

[stephenjubb]

yes can press the button but nothing happens

 

[gbb]

A common winter problem with Sora for me.
If your'e running 8 speed (i dont know if 9 speeds the same)...the mech pivot is prone to seizing.
Look at the mech from the rear, there's a large (ish) dome headed bolt where themech pivots. Undo it slightly (NOT all the way)...spray in some WD40 or oil, manipulate the mech a bit by hand to get the oil in, tighten the bolt....that usually sorts it.

 

[Steve Austin]

Have you tried squirting some wd40 inside the shifter?

 

[Steve Austin]

gbb, just beat me to it!

 

[Adrian_K]

is it the mech or lever that's seized?
can you pull the cable on the down tube with you hand and therefore move the mech? could be a kinked cable.

I don't know how to open them up to look at the rachet system. Could it be that the cable is so loose the nipple has popped out of its recess?

 

[BIGSESAL]

At work in the work shop we spray the mech down with degreaser and then pour some boiling water over the mech (as this will expand the metal and help everything to move better - hot water is fairly useful for many jobs). Then push it from side to side like it would move if you were changing gear. After this spray the mech down (mainly the pivots) with WD40 and push it from side to side again.

Hopefully this will allow everything to move cleaner and easier.

 

[Domestique]

Go for a good lube, but I would use a silicone spray lubricant, works better on plastic parts, like three in one

http://www.screwfix.com/prods/52410...In-One-Oil-Pro-Silicone-Spray-Lubricant-400ml

 

[Bigtwin]

Jamming you say?

Ignore all that rubbish above. Get them in a studio and see if they can cut a decent demo - if not, tell them to can it.

Nothing worse than some awful drum 'n' bass/guitar combo led racket from yer levers when you are trying to enjoy an evening spin - even if they are from the 'hood.

 

[stephenjubb]

I can reproduce the problem and cure it each time. Shift from small ring to middle to large ring, then immediately shift large to middle to small, brake lever then jams and will not move sideways (but can still brake).

Can get lever to work again by pulling on cable then I hear a click from the STI lever.

All done when bike is stationery. Replaced cable with a new one, plenty of grease still does it.

Sprayed plenty of Wd40 inside but couldn't find headed bolt Gbb mentioned above.

any help appreciated

 

[gbb]

I can reproduce the problem and cure it each time. Shift from small ring to middle to large ring, then immediately shift large to middle to small, brake lever then jams and will not move sideways (but can still brake).

Can get lever to work again by pulling on cable then I hear a click from the STI lever.

All done when bike is stationery. Replaced cable with a new one, plenty of grease still does it.

Sprayed plenty of Wd40 inside but couldn't find headed bolt Gbb mentioned above.
any help appreciated

Are you running 8 speed Sora ?. Look at the front derailluer itself.
Place yourself by the back wheel and look at the rear of the derailleur. There's a dome headed bolt facing you in the middle'ish of the derailleur. Its the pivot point of the mech. Thats where they can sieze. Undo the bolt a bit...spray with WD or similar and manipulate the mech with your hand to get the lube into the pivot. Then tighten the bolt back up.

It may not be the problem....but it is a common one on Sora.

 

[stephenjubb]

thanks gbb tried that but no luck